Rich Holmes

Knights on spirals

Wed, 13 May 2026 22:56:50 -0400

The Numberphile video Red & Black Knights (extraordinary result) features Neal Sloane talking about a discovery by Jonas Karlsson; there is a followup video, Amazing Chessboard Patterns (extra) showing some further results.

In brief, take a square grid and number the squares in a spiral pattern:

Now place black and red chess knights alternately on the grid using the following rules:

A knight must be placed on an empty square.
A black knight cannot be placed on a square attacked by a red knight, and vice versa.
A knight must be placed on the lowest numbered square meeting the above requirements.

What Karlsson discovered is that, contrary to his intuition, a strangely complex pattern is produced as the grid is filled in. Here is what you get when you fill the spiral out to a size of 1001 by 1001. (Select thumbnail for full size version.)

The Syracuse Assembly

Sun, 10 May 2026 00:36:04 -0400

It was almost exactly forty years ago — I think late May or maybe early June, 1986, I started to learn morris dancing.

I’d gotten into contradancing the previous January, and after turning up several consecutive weeks at the Syracuse contradance, some of the dancers started asking “So when are you going to join the morris dancers?” I resisted for a while but destiny is inexorable.

The contradances were held in the fellowship hall of Grace Episcopal Church, every Thursday. The Bassett Street Hounds, then a men’s Cotswold morris team, practiced in the same place every Thursday for an hour before the contradance. The contradance paid the hall rental and the Hounds, being led by the same man who ran the contradance, freeloaded. It was a pretty good scam while it lasted, but by the early 1990s we were elsewhere. And I haven’t been back in that room again since then, until Saturday night.

May Day 2026

Tue, 05 May 2026 17:50:42 -0400

Early on May 1 I went to Syracuse’s May Day. 46th annual? It started in 1981, and I think they did something virtual during the pandemic years. Teams dancing this year were Thornden Morris (Cotswold) and the Bassett Street Hounds (border).

Thornden Morris

Bassett Street Hounds

Earthwalk Day 1563 (4 May 2026), 15,680 km: Very Large Array

Tue, 05 May 2026 16:28:43 -0400

My southward path took me right through the middle of Albuquerque. From there along the very pi-ish State Route 314, parallelling I-25 (I like how “parallelling” has two double l in it), up to Sevelleta National Wildlife Refuge, cutting over to US 60 and from there to Old Highway 60 westward to the center of the NRAO Very Large Array. One of those very imaginative astronomical observatory names.

Built in the 1970s, the VLA consists of 28 25-meter radio telescopes, arranged in a symmetric Y each of whose arms is 21 km long. The dishes can be moved to different locations along each arm to make various configurations.

Flipping the contradancing script

Sun, 19 Apr 2026 22:03:50 -0400

I’m so old, I can remember when SUNY ESF (State University of New York College of Environmental Sciences and Forestry, in Syracuse) had its first contradance. That was back about five hours ago.

Not sure about the longer term, but in the past year and a half it seems like there’s been an increasing number of ESF students showing up for the Syracuse contradances. Typically a few at most dances, and once in a while ten or twelve or so in amongst all us, er, post-student regular dancers.

Morris dancing in upstate New York

Sun, 19 Apr 2026 13:27:14 -0400

New update and new address for: Morris dancing in upstate New York — a site about morris dancing in my region.

previous:	Flipping the contradancing script
next:	May Day 2026

Earthwalk Day 1546 (17 April 2026), 15,468 km

Fri, 17 Apr 2026 19:43:52 -0400

Done backtracking, I’m now moving south on Route 313, paralleling I-25, right now in Santa Ana Pueblo. Weather in my real life location has been pretty good but not quite a good enough combination of weather and opportunity to inspire a bike ride in the first half of this month. Tomorrow maybe? Though tomorrow will be busy.

Today I was on foot, though, meeting a small brown frog:

A frog

and a tree that was down, but not out:

How to find out if it's raining

Thu, 16 Apr 2026 08:34:42 -0400

On my Linux Mint computer I used to use an applet that displayed weather conditions in the bottom panel. Used to, because once too often I found it showing numbers that were just way off from reality. It used the Open-Meteo API, and at one point I checked and found some very strange results coming from Open-Meteo, but I think the applet itself may have been misreading the Open-Meteo results too.

Earthwalk Day 1535 (6 April 2026), 15,392 km: New Mexico State Capitol

Mon, 06 Apr 2026 21:16:00 -0400

I spent the past few days hiking into Santa Fe, walking northeast on Agua Fria Street and arriving at the New Mexico State Capitol, the destination for Leg 60.

I’ve been to Santa Fe in real life, though about 32 years or so ago. Just short visits while staying and working in Los Alamos. I don’t recall seeing the Capitol, but it doesn’t surprise me it doesn’t look like any other state capitol I’ve seen. It’s round, for one thing. If you remember the Zia sun symbol I mentioned before, this building is intended to resemble it. Not sure what it’s made of but the exterior certainly resembles adobe. It’s the third newest state capitol in the nation, dating from the 1960s.

Earthwalk Day 1532 (3 April 2026), 15,367 km

Fri, 03 Apr 2026 19:19:28 -0400

Heading northwest, I’m now 121,881 miles from the start of leg 60 — wait, no, that’s Artemis II. I’m 406 km in, approaching the end. As of tonight I’m on Highway 56C about 3 km due west of the Santa Fe Regional Airport, about 1 km from the La Cieneguilla Petroglyphs. Still not a much trafficked area; no Street View imagery.

March went pretty well. Not as many average daily steps as 2024 but better than the other years, and better average daily distance than any previous EarthWalk year. Two bike rides, both about the usual average summertime ride length.

Earthwalk Day 1525 (27 March 2026), 15,306 km

Fri, 27 Mar 2026 21:48:54 -0400

Making my way through rugged terrain north of Albuquerque and about 23 miles southwest of Los Alamos, where my real world self spent some time in the early 1990s. I’m in Zia Pueblo, home to the Zia or Tsʾíiyʾamʾé people whose sun symbol features on the New Mexico flag.

My real world self in the present day is finding the going easier these days. The snow’s gone and things have started drying out; the recreational trails, especially the paved ones, are more passable. Some rain days lately but not bad. Went on a bike ride yesterday, about 35 km.

Earthwalk Day 1511 (14 March 2026), 15,160 km

Sat, 14 Mar 2026 00:01:08 -0400

On Tuesday this week the temperature in Syracuse got up to 21°C (70°F). Thursday evening we had snow accumulating. Welcome to March.

February was a decent month for distance, if a crummy one for weather. I spent a lot more time walking in the enclosed shopping mall than I like to, but my distance would have been a disaster if I hadn’t. As it is my average daily steps was in a dead heat for second place among all months of this EarthWalk. I did two bike rides for the first time in any February, with distances decent for winter, so I had my best February for distance.

Earthwalk Day 1497 (27 February 2026), 15,017 km: New Mexico

Fri, 27 Feb 2026 19:26:25 -0500

Three notable milestones today. The first: For the first time I’ve gone on not zero, not one, but two bike rides in February. Once again it was a good deal colder than I like for riding, but warmer than it’s been, and no precipitation, and the roads were clear, so I went.

The second – well, I suppose it’s a kilometerstone. I crossed the 15,000 km mark. I estimate I’m still less than halfway through the total planned EarthWalk distance! I’ll probably get to the halfway point sometime this summer, though I won’t know for sure until I’m done.

Earthwalk Day 1493 (23 February 2026), 14,966 km: Navajo meteorite

Mon, 23 Feb 2026 21:27:09 -0500

I’m (virtually) within the Navajo Nation, a few km past an utterly unremarkable piece of desert land that was the destination for Leg 59. Nothing to see there, but there was once, and we’ve seen it. Or them. Two chunks of what presumably were once a single piece of nickel-iron material that hit the Earth at some unknown time in the past: The Navajo Meteorite, the third most massive known IIAB iron meteorite.

Pitchers and sandwiches

Sun, 15 Feb 2026 21:47:58 -0500

The theme for next month’s Syracuse Pub Sing is drinking songs, and that led me to look up “Joke and Push About the Pitcher”, a song I’ve heard and sung the chorus of many times. It features the immortal line

No sniveling milksop Jimmy Twitcher

What I found was a discussion on mudcat.org in which Jim Dixon posted two versions, one published in 1781 and one, closer to the versions I’ve heard, published in 1790. In the latter that line is a little different:

Earthwalk Day 1473 (3 February 2026), 14,774 km: Meteor Crater

Tue, 03 Feb 2026 23:35:37 -0500

Meteor Crater, a.k.a. Barringer Crater, is both a meteor impact crater and a weird circle on the map. Actually rather square, as circles go.

Meteor Crater

The crater is 1.2 km in diameter and 170 m deep. 50,000 years ago a meteorite about 50 m in diameter slammed into our planet here and was mostly vaporized. This impact eventually brought about the creation of a visitor center on the north rim, attracting 270,000 visitors each year.

Earthwalk Day 1469 (30 January 2026), 14,742 km

Fri, 30 Jan 2026 20:07:41 -0500

I remember 10 Jan 1982. I was living outside Chicago, and that day, per the National Weather Service, an all time Chicago record low of -32°C (-26°F) was set. The Weather Service page I found doesn’t show the wind chill that day; my recollection is -63°C (-81°F), but take that as mere rumor.

Anyway, it was cold.

I’ve been thinking about that because Saturday’s high temperature in Syracuse was 7°F (-14°C). Which is not warm. I think we’ve had only about a dozen or so colder days in the past 20 years.

Earthwalk Day 1457 (18 January 2026), 14,654 km: Lowell Observatory Mars Hill

Sun, 18 Jan 2026 22:38:22 -0500

As promised, a very short leg. I arrived today at Lowell Observatory’s Mars Hill campus. This is the original Lowell site, established in 1894 by Percival Lowell. Lowell was convinced of Giovanni Schiaparelli’s claim to have observed linear markings on Mars, which he had called canali, meaning “channels” in Italian, but mistranslated into English as “canals” — implying canal builders, i.e., Martians. Lowell built the observatory in large part to study the Martian surface, and was firmly convinced he could see a network of canals. It was all self delusion of course.

Earthwalk Day 1455 (16 January 2026), 14,632 km: Lowell Discovery Telescope and Lowell Discovery Anderson Mesa

Fri, 16 Jan 2026 20:48:27 -0500

Six days ago I reached yet another observatory facility… and I have to admit I didn’t know that until today. I wasn’t really aware of the existence of the Lowell Discovery Telescope, formerly the Discovery Channel Telescope, and it wasn’t on my list of destinations. This scope is part of the Lowell Observatory, which I knew about, but I didn’t know it had three campuses. Fortunately the LDT was right on the route I was following, so I (retroactively) made a stop there, ending Leg 55.

Earthwalk Day 1441 (2 January 2026), 14,503 km

Sun, 04 Jan 2026 08:20:27 -0500

On north into Payson.

2025 is over, and I’m fine with that. December was… acceptable. Average daily steps were in a dead heat with the previous two Decembers and substantially above December 2022. I got only one bike ride in, though, so average distance was low, only slightly above 2022 — even though I had two rides that month. For the year I had fewer steps and less distance per day than 2022, 2023, or 2024. I did 31 bike rides compared to 41, 41, and 37, though the average ride length was significantly higher, 36 km versus 28, 29, and 32.

Fortunately

Sun, 28 Dec 2025 16:56:16 -0500

This Numberphile video talks about the Fortune conjecture, and as presented, it seems quite mysterious. But it’s less so once you think about it.

Let’s start with Euclid’s proof that the number of primes is infinite. If you assume the contrary, that there are exactly $l n$ primes which we can denote $l p_1, p_2, p_3, …, p_n$, then there exists a number $l q=p_1p_2p_3…p_n+1$. That number isn’t divisible by any of $l p_1$ through $l p_n$; there is always a remainder of $l 1$. So either $l q$ is a prime not in our list of “all” the primes, or it is a composite whose prime factors are not in our list. Either way we’ve shown there exists at least one prime not in our list, contradicting our claim that the list was complete. The only way to avoid this contradiction is if the list of primes is infinite.

Earthwalk Day 1434 (26 December 2025), 14,462 km

Fri, 26 Dec 2025 21:05:24 -0500

Continuing northwest, I’ve passed through San Carlos Reservation, past Globe, AZ, on up to Tonto Basin, site of the Tonto Basin Feud and setting of Zane Grey’s To the Last Man, later published in its original, longer form as Tonto Basin. I have to give you these literary references because there certainly isn’t much else to say about this hike. Lots of scrub and distant mountains, that’s about it.

As for real life, I’d waited all month for temperature in Syracuse above 4°C, no rain or snow or icy roads, and little to no wind. Finally settled on Christmas for 2°C and 16 km/h wind and went for a 20 km bike ride. First half of the ride was into the wind and even with lined mittens my fingers were cold and stiff before the halfway point, but once the wind was at my back they warmed up. This morning it got down to -12°C, and today and tonight we’re supposed to get about 15 cm of snow. Happy winter.

Earthwalk Day 1420 (12 December 2025), 14,344 km

Fri, 12 Dec 2025 22:35:58 -0500

I hiked something marked “Crest Trail 130” on the map northeast from Mt. Graham to US 70 at Pima, then headed northwest on 70. That took me onto the San Carlos Apache Indian Reservation and to Peridot (Tséé Dotłʼizh), my current location.

I’ve been making pretty good distance when you consider weather — rain, snow, wind, cold — has kept me from walking on four days these past two weeks, and as for bike rides, forget it. Syracuse has gotten more snow thus far than in any of the past ten years.

Pythagorean concatenation

Thu, 11 Dec 2025 15:27:13 -0500

(This basically is me trying to work out an understanding of one of the comments on this Numberphile video.)

Consider a right triangle whose legs are $l 588$ and $l 2353$. What’s its hypotenuse? Would you believe… $l \sqrt{5882353}$?

Does it make sense? Well. Do those digits look at all familiar to you? Perhaps not, but the decimal representation of the rational number $l 1/17$ is $l 0.0588235294117647\ 0588235…$, a 16-digit repeating decimal. Maybe you know $l 1/7 = 0.142857\ 142857\ 14285…$ is a 6-digit repeating decimal, and any multiple of $l 1/7$ is the same sequence of digits with a different starting point:

Earthwalk Day 1405 (28 November 2025), 14,236 km: Mount Graham International Observatory

Fri, 28 Nov 2025 00:30:40 -0500

Happy Thanksgiving! Before making the turkey and the pumpkin pie and the roasted carrots and the gravy (my son made the rest) I got out for a walk and it took me to the end of Leg 54.

Destination… an (wait for it…) an observatory. Mount Graham International Observatory. Are you getting sick of observatories yet? Tough. This is Arizona.

Mount Graham is the home of the Vatican Advanced Technology Telescope, the Submillimeter Telescope, and the big one, the Large Binocular Telescope. The latter consists of two telescopes which share second place among the largest optical telescopes in continental North America, and when used in combination they have the largest effective aperture of any telescope in the world.

Earthwalk Day 1392 (14 November 2025), 14,090 km

Fri, 14 Nov 2025 19:44:05 -0500

It hasn’t been a good couple of weeks. Especially this past one where it rained or snowed every other day. Forget about bike rides. But it’s been relatively civilized: I went through Patagonia, Sonoita, and Whetstone, past Kartchner Caverns State Park, and on through St David. The latter is only about six miles southeast of Benson, AZ, a familiar name to fans of the gonzo 1970s science fiction movie Dark Star. As of 2011, there is a Dark Star Road in Benson, named for the film. Also, the composer Harry Partch lived in Benson as a child.

The emperor's new tailcoat

Thu, 13 Nov 2025 10:36:39 -0500

There’s an English country dance ball coming up in Syracuse this spring, and I’ve started work on a Regency costume for it. Not wanting to sink vast sums of money into it — and not having much in the way of sewing skills (yet) — I’ve been looking at varied vendors from Samson Historicals to Etsy to AliExpress. No, really, I found some plausible looking trousers on AliExpress for $33. AE is a crap shoot generally, but the reviews are mostly favorable, and I later found the same trousers ($3 more but with free shipping!) on Amazon Marketplace also with mostly favorable reviews, and I figured why not. Apparently they ship with a very long inseam, and I’ll need to shorten them, but I can do that.

From a large family

Thu, 30 Oct 2025 15:02:02 -0400

The clarinet family is said to be the largest woodwind instrument family. That’s putting it mildly. I made a list and came up with around 50 types of clarinets, about half of which are currently being made.

It depends how you count, of course. For instance, I didn’t consider bass clarinets to low E and E♭ as different, but I did list them separately from bass clarinets to low C. Some historical basset horns varied in their lowest notes, and Fox’s alto clarinet goes to low D rather than either E♭ or C, but I only counted one for each key. I didn’t count instruments with different key systems (Boehm, Oehler, Albert, simple…) separately.

Earthwalk Day 1375 (28 October 2025), 13,938 km: Fred Lawrence Whipple Observatory

Tue, 28 Oct 2025 19:15:13 -0400

I reached another observatory today: The Fred Lawrence Whipple Observatory on the summit of Mount Hopkins. I covered the last 34 km on my bike today, having replaced the leaking inner tube over the weekend. The real world route was a lot flatter than the virtual climb up the mountain; I wouldn’t have done that on a bike, I don’t think.

The observatory was built originally in the 1960s and named in honor of astronomer Fred Whipple in 1981, and it includes the MMT Observatory with its 6.5 meter telescope. “MMT” used to stand for “Multiple Mirror Telescope”, presumably because when it was constructed in 1979 the practice of combining light from multiple primary mirrors was novel; these days there are a number of multiple mirror scopes on Earth and in space. It no longer stands for anything because in 1998 the six mirrors (equivalent to a 4.5 meter telescope) were removed to be replaced with a single 6.5 meter primary. That’s a pretty hefty mirror, but at the time there were about eight larger telescopes in the world, and now a dozen or so.

Earthwalk Day 1371 (24 October 2025), 13,874 km

Fri, 24 Oct 2025 20:45:44 -0400

Not a very good couple of weeks. There was one rain-out last week and three this week. I’d wanted to go on a bike ride last week but found the air had deserted one of the tires.

So I’m not getting there fast. At the moment I’m south of Tucson, heading roughly east on a road that does have Street View imagery — but there’s not much to see in it. Google Maps says I just went past Desert Swarm Bee Removal. Up ahead is Sahuarita, with the Titan Missile Museum in a former missile silo, but I’ll be passing south of that. Given better weather and a better inner tube I might finish this leg in a week.

The 2025 morris season

Wed, 15 Oct 2025 21:52:36 -0400

The Binghamton Morris Men in Gilbertsville

Last weekend the Binghamton Morris Men and the B. F. Harridans staged our annual Harvest Home Tour, doing morris dance performances in Binghamton and Endicott. We danced at the Binghamton Farmers’ Market, the Fall Fest in Grippen Park, and the Cider Mill in Endicott.

Earthwalk Day 1359 (12 October 2025), 13,801 km: Kitt Peak National Observatory

Sun, 12 Oct 2025 18:29:12 -0400

As forecast, I completed leg 53 today, arriving at Kitt Peak National Observatory. This is a pretty huge facility, more domes than a state capitals’ convention. There are more than twenty optical telescopes, including the Mayall 4 meter, at one time the second largest telescope in the world, and the WIYN 3.5 meter. There also are two radio telescopes.

Back I go down the mountain.

A map showing my progress is here, a spreadsheet with progress detail is here, and a Google Earth KMZ file is in this Google Drive folder. Present coordinates: 31.958°N, 111.605°W.

Earthwalk Day 1357 (10 October 2025), 13,789 km

Fri, 10 Oct 2025 19:29:05 -0400

I’ve been heading south from Tempe, into the Tohono O’odham Nation. I’m very close to my next destination; I don’t expect to make a lot of distance tomorrow, but I’ll probably get there Sunday.

South of Casa Grande it’s been pretty much nothing but rough desert terrain. You have to zoom Google Maps in quite a lot before any “roads” show up, and they’re just unnamed tracks through the desert. Now I’m climbing upward in the Quinlan Mountains.

Earthwalk Day 1346 (29 September 2025), 13,599 km: Arizona State Capitol and some meteorites

Mon, 29 Sep 2025 20:22:53 -0400

At one point I decided the minimum length for a leg is 7 km, based on that being around 10,000 steps, roughly a day’s walking. Any destinations closer together would be considered joint destinations for a single leg.

But today I was on my bike, and I blew past both the Arizona State Capitol in Phoenix and the Buseck Center for Meteorite Studies in Tempe, about 18 km apart. I’m calling them joint destinations for Leg 51.

Out of space

Tue, 23 Sep 2025 19:05:58 -0400

If it was driving you nuts that links on this blog always had space before and after, so they looked like " this “, there’s good news. It was driving me nuts too. I thought it was a bug in Hugo and I filed a bug report, but was told Hugo doesn’t do that and maybe it was my theme. So I filed a bug report with Gokarna, but then discovered the problem didn’t occur on a new (test) website with the Gokarna theme — only on this site. I dug deeper and discovered it was a faulty layout file. I fixed it and now the links look like “this”.

Into the Black Hole (part 3)

Mon, 22 Sep 2025 21:06:53 -0400

How low (in price) can you go?

Go on Amazon or eBay and you can find lots of imported Chinese clarinets sold directly by the Chinese companies, some at preposterously low prices — plastic B♭ horns starting at under $70, for instance. There also are E♭, A, G(!), and C instruments, with the C clarinets starting at more like $150. And they’re terrible, right?

A decade or so ago most of them would have had pot metal keys that would bend if you looked at them funny, and bad designs, bad pads, bad construction, bad all around. If you took one to a technician to get it fixed up they’d politely tell you “no”. But in recent years, at least some of the Chinese manufacturers have been improving their quality — in some respects.

Into the Black Hole (part 2)

Fri, 19 Sep 2025 20:11:06 -0400

There’s a problem with playing English country dance tunes, or generally music that isn’t specifically for clarinet, on a clarinet. If it’s a B♭ clarinet, as most clarinets lying around are, or an A clarinet, which most professional clarinettists own at least one of, or an E♭ clarinet or an E♭ alto or a B♭ bass or just about any other sort of clarinet, then there’s the problem of sight reading. They’re transposing instruments, meaning that what the clarinettist thinks of as “C” is really B♭ or A or E♭, and they end up playing in the wrong key if they don’t sight transpose everything. There are reasons for that, but this post would be about three or four times longer if I went into them, so just take it on faith.

Into the Black Hole (part 1)

Fri, 19 Sep 2025 11:09:54 -0400

I got it into my head recently to buy a book of English country dance tunes, and to try to play some of them.

Unlike contradance or morris tunes, which seem to be almost universally in G and D major, maybe A major, or their relative minors, the ECD tunes are in a variety of keys, flat as well as sharp. So using a diatonic instrument like a melodeon or a pennywhistle isn’t the way to go, unless you have several melodeons or pennywhistles in different keys, and the skills to sight read on all of them.

Earthwalk Day 1329 (12 September 2025), 13,332 km: Arizona

Fri, 12 Sep 2025 19:49:59 -0400

Today my virtual self arrived in Big River, California, and then crossed the big river — the Colorado — into Parker, Arizona.

I first entered California on 24 September 2024. Then I went into Nevada for 11 days, returning to California on 28 October 2024, and I’ve been there since then until today. In total I spent 342 days in that state, by far a record — previously the highest was 96 days in Idaho.

Earthwalk Day 1320 (3 September 2025), 13,199 km: Old Woman meteorite

Wed, 03 Sep 2025 18:00:51 -0400

I’m at the end of Leg 50. There doesn’t appear to be much here, mainly because there isn’t much here. Nothing to see, really; but this spot, in the flat desert, is as close as Google Maps’ walking directions will get me to the discovery site, up over there in the Old Woman Mountains, of the Old Woman meteorite. We saw that rock back in June on display at the Desert Discovery Center. If I were really here, maybe I could hike cross country and climb up to the actual discovery site — or maybe I couldn’t — and either way, there probably still wouldn’t be much there to see. Instead I can stand here, virtually, and virtually look around and virtually say “OK, this is kinda near the place, huh” and then virtually move on.

Ducklington morris sources

Mon, 01 Sep 2025 17:25:00 -0400

“Traditional” is a treacherous word, defined differently by different people or by the same people in different contexts, but “longevity” is more concrete. How far back do our morris dances go?

The three main morris dance traditions done by the Binghamton Morris Men are Bampton, Chipping Campden,¹ and Ducklington. Bampton is a living tradition, with a continuous history almost certainly back into the eighteenth century and possibly earlier. We can guess it underwent many changes in that time, but some of the dances we do very likely go back two hundred years at least. Chipping Campden, on the other hand, is a living tradition too but the dances go back only to the 1890s, when they were put together by Dennis Hathaway, who based them in part on some information about dances done locally in the 1850s but mostly on his recollection of having seen the Longborough side when he was a child.

Earthwalk Day 1308 (22 August 2025), 13,042 km

Fri, 22 Aug 2025 22:40:59 -0400

My route these past two weeks took me east on Route 78, then south on BLM 191, a dirt road unknown to Google Street View but apparently part of the 1,950 km Juan Bautista de Anza National Historic Trail. That turn seems to have kept me from encountering the Republic of Slowjamastan, a 0.045 square km nation where Crocs are illegal except on National Wear Your Crocs In Slowjamastan Day.

Adventures Among the Stupid Cheap Toroids

Wed, 13 Aug 2025 17:44:31 -0400

Remember Adventures Among the Toroids by B. M. Stewart? Way back in 2008 I borrowed a copy from the university library and built a number of its models, writing about them in a couple of blog posts. Ten years later I built some toroids virtually, using the Antiprism software, and I wrote some blog posts about them too.

(The mentioned Google Drive folder is no more, but here is an un-curated folder full of toroid stuff, it probably has everything that was there: Toroids.tar.gz)

Website move

Mon, 11 Aug 2025 11:28:25 -0400

Due to problems with the .xyz TLD, I’ve moved my website to https://richardsholmes.com. The old domain name is supposed to redirect there, though so far that isn’t working.

Kosmo gets rungled

Website move

Mon, 11 Aug 2025 11:28:25 -0400

Due to problems with the .xyz TLD, I’ve moved my website to https://richardsholmes.com. The old domain name is supposed to redirect there, though so far that isn’t working.

previous:	American Travelling Morrice 48
next:	Ducklington morris sources

Website move

Mon, 11 Aug 2025 11:28:25 -0400

Due to problems with the .xyz TLD, I’ve moved my website to https://richardsholmes.com. The old domain name is supposed to redirect there, though so far that isn’t working.

previous:	Street numbers
next:	Adventures Among the Stupid Cheap Toroids

Website move

Mon, 11 Aug 2025 11:28:25 -0400

Due to problems with the .xyz TLD, I’ve moved my website to https://richardsholmes.com. The old domain name is supposed to redirect there, though so far that isn’t working.

previous:	Earthwalk Day 1294 (8 August 2025), 12,868 km
next:	Earthwalk Day 1308 (22 August 2025), 13,042 km

Earthwalk Day 1294 (8 August 2025), 12,868 km

Fri, 08 Aug 2025 21:34:09 -0400

The American Travelling Morrice ended on Sunday and, as predicted, my walking distance was relatively paltry during the preceding week. My bicycling distance was nil. So July was not a great month from that point of view. And this week, besides my needing to recover from a week of dancing, we had rain on Wednesday, so August isn’t off to a great start either. But I did get a 42.5 km ride in today.

American Travelling Morrice 48

Tue, 05 Aug 2025 08:37:08 -0400

A year ago my friend Ken Kearns spoke up at the 47th American Travelling Morrice (ATM) and proposed to organize the 48th one.

ATM 48 poster (design: Peter Klosky, illustration: Roberta Wackett)

The ATM, modeled on the Travelling Morrice in England, is a group consisting of morris dancers from all over — mostly New England and New York, but also New Jersey, DC, California, Canada, England, Australia, and who knows where else. Most of us dance with teams in our area, but every summer we get together, in a different geographical location each year, and spend a week doing free performances — 25 or so of them. The first ATM took place in 1976 and it’s occurred annually since then, except in 2020–21.

Earthwalk Day 1280 (25 July 2025), 12,757 km: San Diego Air and Space Museum

Fri, 25 Jul 2025 22:22:30 -0400

Wednesday’s walking took me to just 400 meters shy of the end of Leg 49. Thursday and today were not great days for distance — I was occupied with setting up the American Travelling Morrice, which is going to eat into my distance over the next week too — but they totaled 9.4 km, so yeah, that leg’s over.

The destination was the San Diego Air and Space Museum. Their collection includes the command module from the Apollo 9 mission. Unlike Apollos 8 and 10, 9 didn’t get beyond low Earth orbit; their main goal was to check out the lunar module, which was flying for the first time, and to demonstrate rendezvous and docking between the command and lunar modules. Among the tests performed was use of the lunar module descent stage as an emergency backup for the service module engine. Four missions later, Apollo 13 made use of that capability in a genuine emergency.

Earthwalk Day 1269 (14 July 2025), 12,645 km: Palomar Observatory

Mon, 14 Jul 2025 20:25:48 -0400

Leg 48 ended today with arrival at a truly iconic place. When I was a kid, my parents took me to the Corning Museum of Glass where among other things I saw a huge piece of glass — a disk 5.1 meters in diameter. This was the result of the first attempt, in 1934, to cast a blank for what would be the world’s largest telescope mirror. But part of the mold broke during the pouring. The second attempt was successful. The first blank went on display at the museum in 1951. The second became the primary mirror of the Hale Telescope at Palomar Observatory.

Book review: Terminal Alliance

Thu, 26 Jun 2025 11:29:14 -0400

Well, no, this isn’t so much a review of the book Terminal Alliance by Jim C. Hines as it is a review of its marketing.

The book itself is hardly worth reviewing. Not that it’s bad. No, I enjoyed it, and I’ll probably go ahead and read the second book in the series (there are three, I’m not committing at all to the third just yet). It’s nothing profound, just some lightweight space opera, but pretty well plotted and written. I’ll give it four stars out of five.

Earthwalk Day 1250 (25 June 2025), 12,460 km: Big Bear Solar Observatory

Wed, 25 Jun 2025 20:42:56 -0400

Another leg done; I arrived today at Big Bear Solar Observatory on Big Bear Lake. This is an observatory built for study of the Sun, and it contains what was until 2019 the highest resolution solar telescope in the world (and is still the largest such telescope outside Hawaii and China).

I say it’s on Big Bear Lake, but it might be more accurate to say the main building is in Big Bear Lake, or at least pretty much surrounded by the lake. It’s built on the end of a causeway about 200 meters long extending from the northern lake shore. Putting the observatory in the lake helps cool the atmosphere near the building and reduces heat radiation waves that would disturb the path of light reaching the telescope.

Earthwalk Day 1243 (18 June 2025), 12,379 km: Desert Discovery Center

Wed, 18 Jun 2025 20:33:24 -0400

Another leg done. Today’s walk took me to the the Desert Discovery Center. This is an education center in Barstow, California mainly having to do with desert life, which isn’t really our remit. But they have on display something that is: the Old Woman Meteorite.

It presumably is called that because it was discovered in the Old Woman Mountains, which presumably are called that because they include the Old Woman Statue, a rock formation which presumably is called that because it resembles an old woman. It — the meteorite, in case you’ve lost track — is mostly iron and was discovered in 1976. If there are any clues to when it fell I don’t know about them. At 2750 kg originally, it’s the largest meteorite found in California and the second largest found in the United States. The largest was the Willamette, remember? It’s had a few hundred kg sliced off for study, and an 80.5 kg piece was back at the UCLA meteorite gallery; the rest is here.

Earthwalk Day 1233 (8 June 2025), 12,269 km: Two spaceports

Sun, 08 Jun 2025 21:45:37 -0400

Yesterday I completed leg 44, arriving at Mojave Air and Space Port. This was once a civil airport, then a WWII Marine Corps Auxiliary Air Station (MCAAS), then a Navy Air Station (NAS), then a MCAAS again, then a civil airport again. It acquired its present name in 2012.

This is the field used by Scaled Composites for its suborbital crewed spacecraft operations. It was the launch and landing site for the first privately funded human suborbital flight, that of SpaceShipOne on June 21, 2004. It has also served as a launch site for the military Boeing X-37 robotic spacecraft.

Earthwalk Day 1221 (27 May 2025), 12,132 km: Mount Wilson Observatory

Tue, 27 May 2025 20:11:50 -0400

Well.

I mentioned a week and a half ago I was recovering from a medical procedure and that would be curtailing my activities for a few days. About a week ago I resumed walking with a relatively short walk on a level path along the Erie Canal… and I somehow strained a calf muscle. No idea how, just all of a sudden it was hurting. So I took the next three days off, and by Friday last week it felt fine, which was good, because I was heading off that day to the Marlboro Morris Ale for a weekend of dancing. I don’t count dancing as walking steps though (just because it feels perverse to me to claim distance for an activity that doesn’t actually cover any real distance — that plus my walking stride length isn’t applicable, so figuring out an equivalent walking distance is hard). But there was a fair amount of walking over the weekend, too, which I did count — it was, nonetheless, well below my usual. All in all, it’s been a week and a half of underperforming, distance-wise.

Fiftieth Marlboro

Mon, 26 May 2025 19:19:14 -0400

Bouwerie Boys Morris Dancers, Sherborne “Trunkles”

The fiftieth annual Marlboro Morris Ale is over. It rained most of the weekend, though rarely more hard than a sprinkle and it didn’t stop any dancing. I saw numerous old friends including at least one I haven’t seen in a quarter century or so. And newer friends too of course.

Earthwalk Day 1210 (16 May 2025), 12,090 km: Meteorites and spacecraft and rovers and eagles

Fri, 16 May 2025 18:02:47 -0400

Over the past couple weeks I continued east and then south. All on foot until Monday when I went on a bike ride, 39.1 km, that took me to the end of Leg 40. That is, to the University of California, Los Angeles, and more specifically the Geology Building, and even more specifically, the UCLA Meteorite Collection. This is one of the largest meteorite collections in the United States, with over 2400 samples, including a 162 kg fragment of the Canyon Diablo meteorite.

Earthwalk Day 1196 (2 May 2025), 11,965 km

Sat, 03 May 2025 15:58:45 -0400

Continuing on, I’m staying close to the coast. Indeed, mid last week I arrived in Santa Barbara and soon after came within sight of the Pacific Ocean for the first time. Getting from there to Ventura on foot is, very literally, not straightforward; southeast of Dulah, Frontage Road gives out and State Beach Access Road starts up — but a railroad track and the Pacific Coast Highway lie between them. In practice you probably can dash across both but Google Maps doesn’t allow it. Instead it puts you on E Road which winds like a snake up and down and through the steep hills northeast of Dulah, coming out north of Ventura. From there it’s past Oxnard to Camarillo (of Brillo fame).

The 2025 Gilbertsville Tour

Mon, 28 Apr 2025 06:19:35 -0400

Ken Kearns of the Binghamton Morris Men has for many years organized our annual Gilbertsville morris tour. But last fall, knowing Ken was going to be very busy with other things this spring, I told him I thought it would be nuts for him to try to run G’ville too and that someone else should do it. He asked, “Are you volunteering?” and without hesitation I responded, “No!”

But no one else was either, so eventually I agreed to do it. How hard could it be? We’d done the same thing every year since 2018 (skipping 2020–21) and nearly the same thing since 2003. All I’d have to do is make a few phone calls, tell them, “We’re doing the same thing as last year”, they’d say, “Okay”, boom, done.

Earthwalk Day 1182 (18 April 2025), 11,818 km

Fri, 18 Apr 2025 18:32:18 -0400

I just walked past Ostrichland USA.

A map showing my progress is here, a spreadsheet with progress detail is here, and a Google Earth KMZ file is in this Google Drive folder. Present coordinates: 34.599°N, 120.128°W.

previous:	Earthwalk Day 1178 (14 April 2025), 11,786 km: Vandenberg Space Force Base
next:	Earthwalk Day 1196 (2 May 2025), 11,965 km

Earthwalk Day 1178 (14 April 2025), 11,786 km: Vandenberg Space Force Base

Mon, 14 Apr 2025 19:06:41 -0400

[Vandenberg] Space [Force Base] is big. You just won’t believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it’s a long way down the road to the chemist’s, but that’s just peanuts to [Vandenberg] Space [Force Base].

Space Launch Complex-6 at Vandenberg Air Force Base, California

More quantitatively, Vandenberg is 40,104 ha (99,099 acres) in area. It’s been a military base since 1941, was an Air Force base from 1956 to 2021, and has been a Space Force base since then.

Earthwalk Day 1161 (28 March 2025), 11,607 km

Fri, 28 Mar 2025 21:39:02 -0400

I’m continuing south southwest, past Tulare and skirting Corcoran, and after that through a largely desolate area. My path took me through the Kern National Wildlife Refuge and now — well, it appears I’m in the North Belridge Oil Field. Pretty empty around here.

A map showing my progress is here, a spreadsheet with progress detail is here, and a Google Earth KMZ file is in this Google Drive folder. Present coordinates: 35.540°N, 119.801°W.

Earthwalk Day 1147 (14 March 2025), 11,496 km

Fri, 14 Mar 2025 21:18:14 -0400

February was a terrible, horrible, no good, very bad month and the first week or so of March wasn’t much of an improvement. Bad weather in February knocked a few days out and a cold put me out of action for nearly a week. Ice deposits made walking treacherous especially on the recreational trails. Average steps and distance for the month were both record lows.

By March I was starting to feel better but then I lost a weekend to a trip to Massachusetts and another day to a trip to Cooperstown. Wednesday this week was the first time since Feb. 11 I walked more than 10 km, and the day before — when it got up to 21°C (70°F)! — was my first bike ride since Dec. 29. After that, with the ice and snow gone for now, I got a few good long walks in, so I’m on my way back to my previous pace.

Unkindling

Fri, 21 Feb 2025 19:42:33 -0500

I’ve put up with the Amazon Kindle ecosystem for as long as I have, because it’s easier than fighting it, and cheaper than buying a different e-reader device. But it’s gotten harder and harder to justify. As you’ve probably heard, Amazon’s latest slap to the consumer’s face is their announcement that as of Wednesday, you will no longer be able to download purchased ebooks to a computer to be loaded via USB to a Kindle device.

Earthwalk Day 1126 (21 February 2025), 11,343 km

Fri, 21 Feb 2025 19:05:04 -0500

As of last Saturday, it had been something over five years since the last time I came down with a communicable illness. That streak ended Sunday, and I’ve felt crappy all this week. Three home covid tests have shown negative, no fever, so I guess it’s just a cold, but a fairly bad one. Meanwhile we’ve had snow and the temperature hasn’t gone north of -5°C (23°F).

So not much walking.

Kosmo gets rungled

Tue, 18 Feb 2025 16:28:22 -0500

After some breadboarding, I went ahead and designed a rungler in Kosmo format.

Rungler module

I included the loop offset switch and knob discussed in the previous post. Also on the front panel is a feedback switch. This enables or disables sending the output of the last stage of the shift register to be XORed with the input to determine the next bit to be loaded in. Feedback on is the “normal” configuration, hard wired in the Benjolin, but you may find it useful to turn it off sometimes.

LMNC 4051 Plexquencer

Sun, 16 Feb 2025 19:03:08 -0500

The Look Mum No Computer 4051 Plexquencer (description, purchase) is an interesting new module. It’s kind of like your basic eight stage Baby-8 style analog sequencer, except that instead of taking a clock signal, it takes three gate inputs (A through C). Those three gates, interpreted as a binary number, tell the module which of the stages to activate. If the inputs count in binary from 0 up to 7 and back to 0, it’ll go through the stages in order (though they’re numbered 1 to 8, which has already caused me some confusion), like a typical sequencer, but if they form a different binary sequence it’ll do different things.

Earthwalk Day 1110 (5 February 2025), 11,260 km: Owens Valley Radio Observatory

Wed, 05 Feb 2025 20:33:19 -0500

I arrived today at the Leg 38 destination: Owens Valley Radio Observatory.

This facility goes back to 1958, when a 9.8 meter antenna that had been installed at Palomar Mountain was dismantled and rebuilt at Owens Valley along with two new 27.4 m telescopes. Six 10.4 meter dishes were added to the site in the 1980s and 1990s. Research at Owens Valley includes study of a variety of astronomical phenomena.

Earthwalk Day 1098 (24 January 2025), 11,175 km

Fri, 24 Jan 2025 19:32:15 -0500

It’s been cold in Syracuse, and we’ve had some snow, and the recreational trails are icy and hard to navigate, but the suburban streets are as uninspiring as ever, and my knee has done some hurting lately. Excuses, excuses. Anyway, I’m (virtually) out of Yosemite National Park, just past Mammoth Lakes, heading southeast. 83% of Leg 38 is behind me.

I’d show you the photo I took on one of my walks, of a pileated woodpecker, low on a tree trunk, tapping away and not particularly concerned about my being about six meters away, except I didn’t take the photo because it was cold and I didn’t feel like taking my gloves off.

Earthwalk Day 1084 (10 January 2025), 11,072 km

Fri, 10 Jan 2025 23:27:08 -0500

Mountains again. I’ve just entered Yosemite National Park, and in fact am on a hiking trail; it’s marked Old Tioga Road on Google Maps but it’s barely if at all visible in the satellite images (and no, there’s no Street View).

Really, of course, I’m in Syracuse, and it’s winter, off to a more typical start than the preceding several winters. I think in the past week and a half I’ve used the snowblower more than I did in the entirety of last winter. There were about 20 cm (8 inches) in my driveway last Saturday, and smaller snowfalls but still maybe 6–8 cm or so on several days this week. As for temperature, it hasn’t been above freezing since a week ago, and the average wind speed’s been north of 24 km/h (15 MPH) every day except Monday. Altogether not great weather for getting out walking, and I stayed in the first two days of this month (rain on New Year’s, snow and wind on the second), but I’ve since managed to get the average steps up to 10,000 a day, which is where it’s been the previous three Januaries.

The winter of our discontent

Fri, 10 Jan 2025 17:28:51 -0500

December through early January was not my greatest time building.

I have two Kosmo modules under construction. One is an FM Drum, built around a circuit board from Barton Musical Circuits. It needed two SPDT toggle switches, and I had a ton of them in my stash… right? Turns out, no, I didn’t; I had two. So no problem? Except they had no nuts and washers on them, but I have toggle switch nuts and washers lying around loose or in their own little bags all over. Except they don’t work. Apparently these switches have a different diameter or thread than the usual.

Books of 2024

Wed, 01 Jan 2025 23:07:49 -0500

I finished reading 41 books in 2024, just slightly fewer than in 2023, but on average I thought they were considerably better books. But partly that was because a lot of them were re-reads of books I’d liked the first time. Or times. Or they were new-to-me sequels to books I’d liked. Leigh Bardugo’s Hell Bent, for example, sequel to Ninth House which was one of my favorite books of 2023. Razzmatazz by Christopher Moore, sequel to Noir. And Something Rotten, First Among Sequels, One Of Our Thursdays Is Missing, and The Woman Who Died A Lot, books in Jasper Fforde’s Thursday Next series along with three previous volumes I’d read before and liked, though a little less well than the later books.

Earthwalk Day 1070 (27 December 2024), 10,957 km

Fri, 27 Dec 2024 19:20:30 -0500

Two weeks, so far, of heading east and a little north. I came out of the mountains across one of the most startling changes in topography I’ve ever seen.

Topography change

I couldn’t just walk east on Route 130 into Patterson, though. No, at least Google doesn’t think so; I was routed 4 km south, then 4 km east, then 4 km north again. Looking at the Street View imagery I guess it’s clear why: The bridge over the aqueduct has virtually no shoulders whatsoever, and the posted speed limit is 45 MPH (72 km/h). It’s not very far, and I’m not sure you couldn’t wade the aqueduct if you wanted to, but I walked the long way. I passed fairly close to NASA Crows Landing Airport and Test Facility, a former airport belonging from 1993 to 2011 to NASA Ames, after which it was closed. So no, not a NASA facility destination for this tour.

Earthwalk Day 1053 (10 December 2024), 10,825 km: Lick Observatory

Tue, 10 Dec 2024 18:28:16 -0500

December’s weather has been unkind, but today in Syracuse it got up to 10°C for the first time since late November, and it wasn’t raining. Gloomy overcast, but, you know, December. And worse is forecast for the next week or so, so I took a my first bike ride of the month.

Had my ride been on my virtual route heading away from San Jose, it would have involved a slog right up a mountain:

Barton JFET Phaser

Tue, 10 Dec 2024 11:57:22 -0500

I have a new module. This is just a Kosmo format adaptation of the Barton JFET Phaser.

Front view

And yes, once again JLCPCB failed to honor my request to put the order number in my specified location.

I assembled the PCBs following Barton’s instructions, except I omitted the board mounted pots and jacks. (And, as I usually do with Barton designs, I used 100 nF for the bypass caps, and 1N5817 Schottky diodes rather than 10Ω resistors on the power rails.) Instead I used panel mounted components and wired them to the PCB footprints. I mounted the PCBs to the panel with a sheet aluminum bracket clamped between the panel and the bottom two pots.

Earthwalk Day 1045 (2 December 2024), 10,741 km: NASA Ames Research Center

Mon, 02 Dec 2024 20:43:00 -0500

And that is a wrap on Leg 36. All 14 km of it.

No, it’s not the shortest leg of the tour. We’ve already had one shorter, from the Museum of Science and Industry to the Field Museum in Chicago, and I expect there will be about seven more that are also shorter (and that doesn’t count destinations under 7 km apart, which are deemed multiple destinations for a single leg).

Rungler? I barely...

Sun, 01 Dec 2024 08:56:12 -0500

I’ve been breadboarding a rungler. “Cool,” you say. You take another bite of leftover turkey. You chew. You swallow. Finally you say, “So what’s…”

Rungler

Rob Hordijk was a Dutch engineer and synth designer. One of his creations was the Benjolin, a quirky little synthesizer featuring two oscillators, a filter, and a… rungler.

The rungler is a control voltage sequencer based around a digital shift register. In that, it somewhat resembles the well known Turing Machine module. Unlike the Turing machine, the rungler is deterministic, not random, though it is unpredictable enough to render the distinction somewhat, though not entirely, moot.

Earthwalk Day 1043 (30 November 2024), 10,725 km: Stanford Dish

Sat, 30 Nov 2024 17:31:27 -0500

I’ve spent the past two weeks virtually walking from Fairfield southwest to Vallejo, then turning south. Across the Carquinez Strait on the bridge carrying Interstate 680 — but there does appear to be a pedestrian lane, separated from the high speed traffic with concrete barriers. Not the most rewarding walking path around, but Google Maps says it works. From there south to San Ramon, then southwest through Hayward to Newark, and across San Francisco Bay on the Dumbarton Bridge to Palo Alto.

Earthwalk Day 1028 (15 November 2024), 10,579 km

Fri, 15 Nov 2024 18:35:16 -0500

Things have changed. I’m walking and biking through (virtual) civilization. Proceeding generally southwest from Sacramento, I’ve gone though Davis, Dixon, and Vacaville, and am now in the middle of Fairfield, California, headquarters of the Jelly Belly Candy Company. I’m going very southwest now, following the right of way of the old Sacramento Northern Railway where it’s been converted into the Fairfield Linear Park, cutting a very straight path through the city except where it was forced to jog around a gas station. Quite a change from Kansas, Idaho, and even northern California.

Earthwalk Day 1023 (10 November 2024), 10,510 km: California State Capitol

Sun, 10 Nov 2024 16:57:24 -0500

I arrived today at the destination for Leg 35, the California State Capitol in Sacramento.

Guess what it looks like. Yep.

California State Capitol, also California State Capitol, ca. 1926

Yeah. Exciting.

Sacramento’s a good sized city, 35th largest in the US and growing fast. There’s a good long Wikipedia article, which I sum up as follows: It’s a city. I mean, is there anything really interesting about it? Not that I can see.

Earthwalk Day 1010 (28 October 2024), 10,333 km: Californiagain

Mon, 28 Oct 2024 20:45:03 -0400

I’m back in California.

I was only in Nevada for 11 days. That was enough. Now I’m in South Lake Tahoe, heading southwest.

I haven’t reported on any wildlife sightings in a while, but there have been some in recent weeks. A few snakes:

Number One Snake

Number Two Snake

Number Three Snake

a frog:

Earthwalk Day 1005 (23 October 2024), 10,293 km: Nevada state capital

Wed, 23 Oct 2024 20:53:49 -0400

It got up to 26°C (79°F) today, and tomorrow’s high temperature forecast is 12°C (53 °F), so I got on my bike for what may be my last ride in shorts for a while and rode to and beyond the destination of Leg 34: the Nevada State Capitol. That’s in Carson City, one of the largest state capitals at 380 square km area because in 1969 Carson City merged with Ormsby County. There are 13 state capitals with smaller population, which is more than I’d expected.

Earthwalk Day 1000 (18 October 2024), 10,191 km: Nevada

Fri, 18 Oct 2024 23:40:42 -0400

As of yesterday, I am in Nevada, my 23rd state. I spent 23 days on my first entry into California. I’ll be back in that state again soon.
Today is EarthWalk day 1000.

That is all.

A map showing my progress is here, a spreadsheet with progress detail is here, and a Google Earth KMZ file is in this Google Drive folder. Present coordinates: 39.855°N, 119.935°W.

previous:	Earthwalk Day 993 (11 October 2024), 10,139 km
next:	Earthwalk Day 1005 (23 October 2024), 10,293 km: Nevada state capital

Earthwalk Day 993 (11 October 2024), 10,139 km

Fri, 11 Oct 2024 22:55:48 -0400

I’m not sure I’m supposed to be here.

My virtual self is virtually heading south, close to the Nevada state line, and right now I’m very near an Army air base. From the satellite views it looks like what I’m on barely qualifies as a track, let alone a road, and the boundaries of the Army facility are not at all clear. If you don’t hear from me again for a while, I’m probably in virtual jail.

Let's not go there

Thu, 26 Sep 2024 19:43:33 -0400

It didn’t occur to me to include the following places in my route plan until well after I’d started. Now I’m not going back to the ones I’ve already passed, and I don’t want to include the others without including them, so I don’t plan on visiting any of them.

But I probably should have included:

(Or somewhere like them; many of these are only one of several places with the same or similar name. Which is probably another reason not to include them, and be accused of favoritism. A third reason is some of these places’ names have nothing to do with the same-named celestial bodies; Pluto, MS, for instance, got its name by 1886, long before the dwarf planet was disovered and named.)

Earthwalk Day 977 (25 September 2024), 9922 km: Goose Lake Meteorite

Wed, 25 Sep 2024 21:04:39 -0400

Virtual me rode my bike into the northeastern corner of California, my 26th state, yesterday. That was 42 days spent in Oregon this time, 71 days total when you add in the earlier entry en route to LIGO Hanford.

Today I walked a bit further and arrived at the destination for Leg 32. It’s a pretty nondescript piece of desolate, scrubby land, on a road forsaken by the Street View car, but like Oregon City it’s the discovery site of a significant meteorite. The Goose Lake Meteorite, found in 1938, is named for, um, Goose Lake, which is nearby. It’s 1170 kilograms of iron, and yet there was no crater at the site. Vagn F. Buchwald, in the Handbook of Iron Meteorites, suggests it could have been carried from its original impact site to Goose Lake by lava flows, the meteorite showing signs of reheating above 400°C; Buchwald also allows the possibility it was transported by glacier action, like the Willamette meteorite, and later subjected to heat from intense forest fires.

Dean and Bedlam

Thu, 19 Sep 2024 07:46:08 -0400

Start with disclaimer: I am not a morris historian. I don’t know what the current state of knowledge is. I assume someone else has already thought about the following, and maybe refuted it.

Continuing on the subject of the Forest of Dean morris, here is an intriguing entry from Keith Chandler’s Chronological Gazetteer (under Blackwell, Warwickshire):

The Cooper family were said to have come ‘originally from the Forest of Dean and brought the dancing tradition with them.’ Relevant parish registers reveals that there are members of that family in the village by 1765, at least, and at nearby Honington by 1670.

Forest of Dean morris

Tue, 17 Sep 2024 19:19:14 -0400

A few days ago I was looking at some writings by Keith Chandler and noticed there was one I hadn’t paid much attention to before, about morris dancing in the Forest of Dean. It occurred to me that this was something I knew nothing at all about, so I started reading. A friend of mine sent me a copy of an article by Russell Wortley, and I found articles by Roy Dommett and Michael Heaney, and other resources, online.

Morris women

Tue, 10 Sep 2024 08:09:37 -0400

The idea that women’s morris dancing is a 20th century revivalist invention seems to be widely believed. Early revival folklorists like Cecil Sharp took it as gospel that the morris had always been an exclusively male activity, hypothesizing without evidence a connection to pagan fertility rites conducted by a male (of course!) priesthood. But even in Sharp’s day, women’s long historical role in morris dancing was known, and simply dismissed or ignored.

Earthwalk Day 958 (6 September 2024), 9641 km

Fri, 06 Sep 2024 19:17:10 -0400

Having gone south from Salem, Oregon for a couple weeks, past Eugene, I’m now going more southeastward, stopping today not too far from Diamond Peak. If you don’t like tall evergreen trees, Highway 58 is not for you. If you get bored looking at the tall evergreens on your left, you can, for variety, look at the tall evergreens on your right. Some way ahead is Diamond Peak Lookout Point where you get close enough to have Odell Lake on your right instead of the evergreens; in the Street View pictures the distance is foggy, but perhaps on a clear day you can see Diamond Peak which is, I’m guessing, covered in tall evergreens up to the altitude where it transitions to being covered in nothing whatsoever, except maybe snow.

Kosmodrome's new instar

Thu, 05 Sep 2024 12:18:29 -0400

I’ve been working the past several weeks on my traditional summer activity, expanding my synth cases (too cold in the garage workshop for woodworking in winter), and reassembing Kosmodrome. I’ve added two rows to the bottom of the second case.

Kosmodrome case extension

Kosmodrome case with extension mounted at bottom

The woodworking is, erm, imprecise, and the finish is positively slapdash, but good enough.

Earthwalk Day 940 (19 August 2024), 9422 km: Oregon State Capitol

Mon, 19 Aug 2024 19:49:30 -0400

A lot of these legs have been long, arduous treks. Leg 31, not so much.

It was rainy yesterday and today in Syracuse, but just a little drizzle this afternoon, not enough to impede my walking. So I covered enough distance to (virtually) arrive at my next destination, the Oregon State Capitol in Salem, OR. And I don’t know if I like it much, but much respect for not looking damn near indistinguishable from almost every other state (and national) capitol building in America.

Vids

Fri, 16 Aug 2024 20:45:59 -0400

As Google becomes more and more repulsive I’ve looked for alternatives for some of their products. For a while now I’ve used diode.zone, a PeerTube instance, for some synth related videos. PeerTube is an open source, decentralized video platform. In other words, a place (or rather, a bunch of places) to post videos that isn’t under the control of some narcissistic billionaire or a huge corporation intent on sucking up as much money as possible.

Earthwalk Day 935 (14 August 2024), 9357 km: Willamette meteorite site

Wed, 14 Aug 2024 19:32:34 -0400

Yesterday I took a bike ride. It was, by just a few hundred meters, the longest I’ve done in recent years, about 41.1 km. And it took virtual me across a state line. I left Washington, where I’d spent 60 days, and made my second entry into Oregon, crossing the Columbia River on the aptly named Oregon-Washington bridge from Victoria, WA to Portland, OR.

Today I walked about 7 km to arrive at the end of Leg 30.

Invented traditions

Wed, 14 Aug 2024 07:51:31 -0400

I’ve never liked the use of the word “tradition” to refer to a locality’s sub-style of Cotswold morris and its repertoire of dances. For one thing, there is more to a locality’s morris tradition than that. “We do the Bampton tradition” — no, you don’t; you do dances from Bampton in the Bampton style. The Bampton morris tradition includes much more: The context in which it occurs, who does it, when they do it, where they do it, why they do it, what they do besides the actual dances, and so on.

Dog Days Ale 2024

Sat, 10 Aug 2024 21:32:28 -0400

B. F. Harridans at Watkins Glen State Park

Today I went to Watkins Glen (NY) to watch the Dog Days Ale, a morris dancing event staged by Syracuse’s Bassett Street Hounds. Teams present were the Hounds, B. F. Harridans (Binghamton), Charles River Rapper (Boston), Hart’s Brook Garland (Western Massachusetts), Pokingbrook Morris (Albany), Snowbelt Morris (Rochester), Thornden Morris (Syracuse), and Whistle Pig Morris (Boston).

Earthwalk Day 919 (29 July 2024), 9168 km: Washington State Capitol

Mon, 29 Jul 2024 20:07:18 -0400

Real life me is back home. As expected, I mostly didn’t cover my usual distances while away, though on Wednesday I took a walk on the Delaware-Raritan Canal trail that, along with a lot of walking back and forth at camp, resulted in a record-destroying 22,142 steps for that day. That, not too surprisingly, was also the day I ended Leg 29, with virtual me arriving in Olympia, Washington, the state capital. The State Capitol, well, it looks familiar.

American Travelling Morrice 2024

Mon, 29 Jul 2024 09:45:27 -0400

The 47th tour of the American Travelling Morrice is in the books. This year we were in Central New Jersey, with a few stands on the Pennsylvania side of the Delaware River and a day in New York City.

American Travelling Morrice at Hillbilly Hall, Hopewell, NJ

It was a small tour. For the first few days we had, I think, twelve or thirteen dancers and no dedicated musician. There were a few more after the Wednesday off. Weather was uncomfortably warm, high temperatures mostly low 30s°C/high 80s°F all week.

Earthwalk Day 909 (19 July 2024), 9099 km

Fri, 19 Jul 2024 21:21:19 -0400

Too busy to write much, but there isn’t much to write. I’ve been continuing west and a little north. A week ago I was just maybe 20 km south of the summit of Mount Ranier. Now I’m between McKenna and Yelm, approaching Olympia.

At my typical pace I’d finish this leg by about Monday, and normally I’d hold off on blogging anything until then. But I’m spending next week on the American Travelling Morrice so (a) I don’t expect to keep up my typical pace (steps while dancing don’t count, they don’t get you anywhere) and (b) I may not have a chance to post to this blog until after I get back. So you get this not-much-of-an-entry now and maybe a belated end-of-leg post in about 10 days. Stay cool until then.

Earthwalk Day 895 (5 July 2024), 8916 km

Fri, 05 Jul 2024 19:26:14 -0400

I’m heading mostly west, a little north, across Washington. This week I passed right through downtown Yakima. That glimpse of urban landscape was short lived. Not far beyond, I’m back in rural areas, heading into the Cascade Range. Tonight I’m near the very small city of Tieton.

June was a pretty good month. Average steps per day slightly up from May and slightly higher than June 2022, much higher than 2023. Average distance per day also up from May and midway between the previous two Junes. Only four bike rides versus the five in Junes 2022 and 2023, due mainly to a lot of hot weather. It’s also been fairly hot these first few days of July, but I got a ride in yesterday.

Morris, sex, and gender in the 2020s

Sun, 30 Jun 2024 20:03:38 -0400

I’ve decided to turn the original content of this blog post into a more readily updatable web page, found here:

Morris, sex, and gender in the 2020s

previous:	Foot up
next:	American Travelling Morrice 2024

Morris, sex, and gender in the 2020s

Sun, 30 Jun 2024 20:03:38 -0400

Rich Holmes

A work in progress. Constructive comments and corrections via email (rich@richardsholmes.com) welcomed — feel free to use a burner address if you want to comment anonymously.

Originally posted 30 Jun 2024. Corrected and updated 1 Jul 2024. Significantly restructured and revised 5 Jul 2024. Further minor edits July 2024. Added ideas about “men’s morris” as a prescriptive or a descriptive idea, and removal of some unsatisfactory discussion of the “why” of single sex morris and of going mixed, March 2025.

Earthwalk Day 884 (24 June 2024), 8786 km: LIGO Hanford Observatory

Mon, 24 Jun 2024 22:47:28 -0400

Yesterday I managed to stop my walk about 300 meters short of my Leg 28 destination. Today I got there.

A week ago Friday I crossed the state line into Washington. I would have blogged that but Friday I also departed for a real life weekend event, and by the time I got back I figured I might as well wait until I reached the end of the leg, but then that took longer than expected due to the heat wave in my real life location. Anyway, I was in Oregon for 29 days, just passing through this time. I went northwest through Kennewick and today reached a great big L-shaped facility: the LIGO Hanford Observatory.

Foot up

Mon, 17 Jun 2024 21:15:48 -0400

I recently went through a large number of photographic prints and slides, throwing them away. Well, not all of them. But a great majority of them — mostly photos taken by me or my ex wife between about 1985 and 2005 or so — were either pictures of things that no longer mean much to me, or pictures of things that never did mean much, or pictures of things that do mean something I’d just as soon not be reminded about, or pictures that were hardly distinguishable from a dozen other pictures, or pictures that simply were bad and didn’t merit hanging onto in the first place. I hung onto several dozen and scanned them. I have a lot more photos in digital form mostly from 2005 on, and by the same criteria I could get rid of most of them, but since they don’t take up space I don’t mind keeping them.

Binghamton Morris Men 50th happened

Sun, 16 Jun 2024 17:49:06 -0400

Recreation Park, BMM 50th anniversary event, 15 June 2024.

A good weekend attending the Binghamton Morris Men’s 50th anniversary celebration. (The team was founded by mostly some SUNY Binghamton (now Binghamton University) people in 1973.) Aside from a few locals and some Bouwerie BMMs who opted for a hotel, most of us stayed at Chenango Valley State Park. Friday evening we gathered for spiedies at one of the tent sites. Some went off to view videos and photos, and consume Lagavulin, afterward, but I went to bed.

Morris ails

Sat, 01 Jun 2024 21:09:44 -0400

Dancers at the 2024 Marlboro Morris Ale

American morris ales (large morris dancing events) look to be an endangered species.

I was idly wondering about the Toronto Ale (held by Green Fiddle Morris, Toronto, ON) and went looking online… and couldn’t find anything recent about it. There was one in 2018, and from 2019 there are photos on the Toronto Morris Men Facebook page of what they referred to as “The Toronto Ale (Lite)” — apparently just six teams, all from Ontario. Then an unsurprising “VirtuAle” in 2020, and I can’t find anything since then.

Earthwalk Day 860 (31 May 2024), 8522 km

Fri, 31 May 2024 19:32:20 -0400

Cutting northwest across northeastern Oregon. I’m now just south of Hutchinson, which just barely exists: The Hutchinson post office opened in 1900 and closed in 1902. There’s nothing but farms visible there in Google Maps satellite view.

In May my average steps per day was a little above that in May 2022 and 2023, though lower than February through April of this year. But that’s in part because of four bike rides that helped put my average distance per day higher than the previous three months and in a dead heat with the previous two Mays.

Binghamton Morris Men: 50th

Tue, 28 May 2024 19:51:57 -0400

The Binghamton Morris Men

Congratulations to the numerous American morris dancing teams observing their 50th anniversaries this year. The American morris revival really exploded in 1974! I don’t remember what existing teams date back to that year so I won’t try, but well done, all!

Where [else] I am online

Mon, 27 May 2024 23:59:33 -0400

Here’s where you can find me online, besides here. Note a lack of Facebook, Instagram, X, and other big corporate products with the exception (for now!) of YouTube. Been there, done that, walked away.

GitLab: https://gitlab.com/rsholmes
- Mostly synth DIY hardware designs, some software
General video: https://www.youtube.com/@RichardHolmesSyr
- Videos about anything I’m sufficiently motivated to make videos about except…
Synth DIY video: https://youtube.com/@analog_output
- Videos about building synth modules
PeerTube: https://spectra.video/@rich_holmes
- Also videos. Some posted here a week or so before YouTube, some posted here exclusively.
Photos: https://www.richardsholmes.com/photos/
- Albums of photos
Pixelfed: https://metapixl.com/doctroid
- Social sharing mostly of single photos
Fediverse (general): https://vmst.io/@doctroid
- My one real social media platform
Fediverse (morris/folk): https://folksocial.org/@doctroid
- The account you can mute if you hate morris dancing
LMNC Discourse: https://lookmumnocomputer.discourse.group
- One of the few web forums I can stand — synth DIY stuff

Marlboro Morris Ale

Mon, 27 May 2024 17:46:18 -0400

At the end of last month I suddenly decided I wanted to watch the Marlboro Morris Ale which took place over the long weekend. The Binghamton Men were not going so I would be on my own as an audience slash groupie. Not even bothering with looking at hotels or B&Bs, I went to the Vermont state parks website in search of a tent site. Molly Stark Park, nearest to Marlboro, was full, but Woodford, about 20 miles west of the college, had three, count them three, sites still available. I drove there and set up my tent Friday, hung around during the day with the morris dancers on Saturday and Sunday, and drove back today.

Photos

Wed, 22 May 2024 18:20:40 -0400

Hey, look up there (top) (right) (next to Blogs)! A new menu item!

After yeeting Google Photos I was using Pixelfed but discovered it doesn’t really serve the same purpose — it’s more oriented toward social sharing of individual pictures, not for galleries of large picture collections. So now I’ve set up self hosting of my photos using Piwigo at Rich Holmes’s photos. Which involved setting up mySQL but that wasn’t too bad, and installing Piwigo itself was easy.

Earthwalk Day 845 (16 May 2024), 8366 km: Oregon

Thu, 16 May 2024 19:29:22 -0400

I’m in Oregon now, bicycling over the line this afternoon. This is kind of momentous: Having started about 28 months ago in a state that borders on the Atlantic Ocean, I’ve now arrived in one that borders on the Pacific. I’ll get much closer to both oceans before I’m done, but that’s something for now.

My second entry into Idaho lasted 58 days, which added to my first entry comes to a total of 96 days in that state — by a solid margin the largest amount of time I’ve spent in any state so far. (Fear not, though, California is coming! And it’ll blow Idaho out of the water.)

Earthwalk Day 836 (7 May 2024), 8273 km: Idaho State Capitol

Wed, 08 May 2024 10:39:56 -0400

My bike’s been to the shop and back, twice: Now it’s tuned up, with a new chain, new brake cable, new bottom bracket, and new pedals. Took it out for a short ride the day I picked it up and a longer ride the next day, which took me past the end of Leg 27: the Idaho State Capitol in Boise.

State Capitol, Boise, Idaho in the 1940s

Which looks a lot like the United States Capitol, doesn’t it? It was built in 1905 and, per Wikipedia, it has 219 pillars in the original building.

Gilbertsville 2024

Thu, 02 May 2024 22:45:55 -0400

Last weekend was the Binghamton Morris Men’s Gilbertsville tour and I probably have not enjoyed any Gilbertsville tour more than this one. Part of that was my own situation: I had not fully attended G’ville since five years ago. In 2022 I went only on Saturday and participated in the outdoor dancing; of the 35 or so people who spent the weekend in the Major’s Inn, at least 8 tested positive for covid by the following Wednesday, which made me feel vindicated, though not happy. I did the same in 2023, but no one to my knowledge got sick. This year I decided to go all in. I still have qualms about the thought of being indoors with that many people, but in practice I didn’t think about it much. Four days after it ended I’ve had no symptoms of anything, so I think I got away with it.

Book review: The Invisible Life of Addie LaRue by V. E. Schwab

Thu, 02 May 2024 15:24:15 -0400

My first reaction on starting to read The Invisible Life of Addie LaRue by V. E. Schwab was annoyance. It’s written in the present tense, and that always annoys me. It always strikes me as pretentious, as a flimsy code for “this is not light reading, this is a serious piece of literature”. But I kept reading — and decided that was the only thing I didn’t like about the book.

Earthwalk Day 818 (19 April 2024), 8071 km

Fri, 19 Apr 2024 22:38:02 -0400

More southwesting through the mountains. Current virtual location is near Sunbeam, Idaho, on a road that does have Google Street View, but the imagery is 17 years old.

No complete rain-outs the past two weeks, though one day’s walk was truncated by weather. Another day fell victim to a trip to Gilbertsville, NY to put up posters for our upcoming morris dancing tour, and another had very limited walking because I was driving 12 hours to get to a favorable location to sit and watch the sun disappear. But I did get a bike ride in, not too lengthy — I was still recovering from eclipse day — but it got the distance back up closer to good.

Weirdness [B]

Thu, 18 Apr 2024 23:13:24 -0400

Weirdness is a Kosmo format synth module based on the Music From Outer Space Weird Sound Generator by Ray Wilson. For this module I incorporated the WSG’s two three-oscillator voices but omitted the filter. I figured we all have filters already in our synths, use them! Instead the two voices go to (separate) mixing and buffering stages and output jacks. There are also gate outputs, with indicator LEDs, derived from the Zany oscillators. Other than that the circuit is taken directly from Wilson’s design, except that it is powered with the synth’s ±12 V instead of a 9 V battery.

Weirdness

Tue, 16 Apr 2024 07:12:24 -0400

Here, have some Weirdness.

Weirdness

Weirdness is a Kosmo format synth module based on the Music From Outer Space Weird Sound Generator by Ray Wilson.

Pulses and gates

Sun, 14 Apr 2024 10:11:58 -0400

The Halting Problem, based on the Music Thing Modular Turing Machine, has pin headers for connections to expansion modules like the HP Potentials and HP Gates. One of these headers is marked GATES1 and the other is PULSES1. Normally expansion modules connect to one or the other, but what if you want to switch between both?

The GATES1 header is connected directly to the shift register output pins. As long as a particular shift register entry contains a 1 bit, the corresponding GATES1 level will be high.

Total eclipse 2024

Tue, 09 Apr 2024 07:18:09 -0400

or how I ended up driving twelve hours to Vermont and back for the weather

Sunday in Syracuse would have been a great day for a solar eclipse. Clear blue skies. Comfortable temperatures. Couldn’t ask for better.

Blue skies

But that wasn’t eclipse day. It was rehearsal day.

I tried out my two cobbled-together pinhole cameras. One shorter with a smaller but brighter image than the other.

Earthwalk Day 804 (5 April 2024), 7938 km

Fri, 05 Apr 2024 21:45:16 -0400

Well, this month is starting off about as bad as any EarthWalk month ever has. I didn’t get my bike back until Tuesday, and not only has it not been biking weather since then, three out of the five days in April so far have been chilly and rainy, keeping me indoors. Tomorrow should be walkable, I think, and things definitely should improve by Sunday (for however long).

March wasn’t bad. Steps and distance were down compared to February, but both were well above March 2022 and 2023.

Street numbers

Sat, 30 Mar 2024 10:45:09 -0400

On the Fediverse, Christian Lawson-Perfect asks:

Who can find a street with a number in its name that’s bigger than the number of any building on that street?

Well, it’s not hard to find Million Street in Athens, Tenessee, for instance.

Then there’s Billion Dollar Road in Conewango, New York.

But that’s small change compared to Trillion Street NW in West Salem, Oregon, which is… probably one of the smallest streets in the world:

Earthwalk Day 790 (22 March 2024), 7838 km: Into Idaho, again

Fri, 22 Mar 2024 21:44:10 -0400

Idahoveragain! On Tuesday I crossed back into Idaho from Montana. This time I’m heading southwest. I spent 61 days in Montana.

I’ve had three bad weather days the past two weeks, and few good biking days — and no bike rides at all, because the bike really needed a tuneup and a new chain and tires. So it’s in the shop. If it gets done soon, as they said it would, I may be able to get one more ride in this month in between the snow and rain and wind and cold days. Ah, March.

Nuclear Decay video

Thu, 14 Mar 2024 13:06:50 -0400

previous:	Wave Displacer
next:	Pulses and gates

Earthwalk Day 776 (8 March 2024), 7733 km

Fri, 08 Mar 2024 18:48:07 -0500

February went quite well, as winter months go. One bike ride and only a couple of rainy days, so distance was well above January or previous Februaries, and daily steps was by a comfortable margin the highest of any month in the EarthWalk so far.

I’m heading southwest on the non Street View Route 569. I passed through the town of Deer Lodge, MT and near Anaconda sometime this past week, but there’s a lot of nothing around me now. I’m heading toward Wisdom, for once in my life.

Wave Displacer

Mon, 04 Mar 2024 19:48:47 -0500

I call this a Wave Displacer:

It’s a wave shaping module that will work on low or audio frequency waveforms. The idea is simple: Any part of the waveform that is above a threshold gets displaced upward or downward. Any part that’s below a second threshold also gets displaced upward or downward. With low frequency waveforms this gives more complex wave shapes for interesting modulation possibilities. With audio waveforms it adds harmonic content. The result depends on five parameters: The two thresholds, the two displacement amounts, and the amplitude of the original signal. All five parameters are voltage controllable.

Three new ones

Mon, 04 Mar 2024 17:39:34 -0500

I finished up three modules recently:

Nuclear Decay and Bong0

On the left is Nuclear Decay, which I’ve written up. All that’s new is the fabbed front panel — and the piece of clear acetate film I glued behind the window, to protect the Geiger tube and the user from one another.

Moving offline

Sat, 02 Mar 2024 08:31:01 -0500

A week ago, on my Google Mail account, I had an email archive dating back to late 2004. A week ago, on my Google Photos account, I had an archive of photos some from as far back as the 1950s, but in large numbers starting also about 2004.

Right now on Gmail I have emails going back to [checks notes] February 16, and on Google Photos I have [checks notes again] one photo.

AO CVT [SB]

Thu, 29 Feb 2024 10:32:18 -0500

This is a utility module for voltage range conversion. A voltage in any of the three ranges 0–5 V, 0–10 V, or ±5 V can be converted to any of the other two — or to itself, for that matter. Input and output are DC coupled and mainly intended for control voltages, but audio signals also can be converted. Input impedance is 1M and the output current limiting resistor is in the loop, so if the resistors are well matched a conversion from ±5 V to 0–10 V or vice versa, or any range to itself, should accurately preserve the scale of a signal.

NLC Bong0

Thu, 29 Feb 2024 10:32:18 -0500

This is a Kosmo conversion of the Nonlinear Circuits Bong0 twin t drum module, or rather two Bong0s — two of the NLC circuit boards mounted behind a single Kosmo panel. Aside from moving some of the board mounted panel components to panel mount, and inadvertently using green instead of blue LEDs, I didn’t modify anything.

Git repo

Nuclear Decay [S]

Thu, 29 Feb 2024 10:32:18 -0500

This is my version of TimMJN’s Geiger counter module. It uses a commercially available Geiger counter PCB along with an auxiliary circuit on protoboard to create a decay envelope whenever the Geiger counter fires. I added a trigger output as well, and a window on the front panel to allow viewing the Geiger tube — and to reduce the amount of material particles have to get through, at least from that direction. There is a spacer sticking out above the window, for hanging a radioactive source.

Earthwalk Day 762 (23 February 2024), 7584 km: Montana State Capitol

Fri, 23 Feb 2024 19:40:41 -0500

I’ve arrived in Helena, the capital of Montana and goal of Leg 26.

The State Capitol was completed in 1902, but by 1912 had been expanded with two new wings. It looked like this then:

Montana State Capitol, Ca. 1915 postcard view, with the State Seal.

and it hasn’t changed much since.

IM-1 on the moon

Thu, 22 Feb 2024 18:39:25 -0500

It’s official: An American spacecraft has landed on the moon, the first since Apllo 17. The Intuitive Machines IM-1 mission put their uncrewed Nova-C lander, Odysseus, on the lunar surface at around 6:30 pm EST (23:30 UTC). The landing site is Malapert A crater, only about 300 km from the South Pole — which means, had this occurred during my MoonWalk, I very probably would not have added it to my itinerary because it would have taken a long time to walk there and back! Congratulations to everyone involved.

DSO138 Oscilloscope video

Mon, 19 Feb 2024 19:03:29 -0500

previous:	Fumbling with SMD
next:	Three new ones

Fumbling with SMD

Sun, 18 Feb 2024 07:47:31 -0500

Back in 2020 I built two modules using mostly SMD components — one was problematic and I needed outside help with it, the other went OK. Then I got into Kosmo, and there aren’t many SMD Kosmo modules out there and I was designing my on PCBs through hole for the most part. I did build a VCO using the MFOS PCB with one SMD part, and my output module used an SMD amplifier you can’t get as through hole, but that was it.

Earthwalk Day 748 (9 February 2024), 7462 km

Fri, 09 Feb 2024 20:54:00 -0500

Phil, never mind six more weeks of winter. Tell me, when do we get the first six weeks?

We’ve had ridiculously little snow so far this winter in Syracuse — little compared to what we usually get, which is a lot compared to most places. In fact, it’s time to stop comparing to usual and start comparing to the record low. As of today we’ve had 70.9 cm (27.9 inches) this winter. That is second (for years since 1933) only to 1937–38 when we had 67.1 cm (26.4 inches) by February 9. Previously in second place was 2011–12 with 80.8 cm (31.8 inches).

Earthwalk Day 729 (21 January 2024), 7293 km: Beaverhead Impact Structure

Sun, 21 Jan 2024 19:20:29 -0500

I’ve reached the endpoint of Leg 25: The Beaverhead Impact Structure. This is the second largest impact structure yet identified in the United States. (We’ll get to the largest one eventually, be patient.) Per the Earth Impact Database it is 60 km in diameter and was created about 600 million years ago — though the Crater Explorer site says 100 km diameter and an age anywhere from 500 to 1000 million years. In any case it predates or just barely postdates the earliest comb jellies, sponges, and corals. Land based eukaryotic life back then was restricted to plants. So no, no one was watching when it hit.

Nuclear Decay meets autunite

Sat, 20 Jan 2024 22:11:29 -0500

So I did a little followup research and found this site:

geigercheck.com

and… well, today I got a package in the mail:

Just a harmless package

Inside was a little rock:

Autunite piece in visible light

and a small UV light that makes the rock do this:

Autunite piece in UV light

And if I put the little rock close to the Nuclear Decay module’s Geiger tube, it does this:

Ringer video

Sat, 20 Jan 2024 18:25:12 -0500

Ringer video!

https://diode.zone/w/tqo7v2pCiqN2RwK6AWg6YT

(I’ll be posting new videos first at diode.zone, an ActivityPub federated PeerTube instance, then later at YouTube.)

previous:	Nuclear Decay meets autunite
next:	Fumbling with SMD

Earthwalk Day 726 (18 January 2024), 7267 km: Montana

Thu, 18 Jan 2024 18:50:14 -0500

I’m done with Idaho. For now, that is. I haven’t yet visited its capitol, and it kind of stands between me and Washington, so I’ll be back, but for now I’m in Montana.

Idaho was 38 days of basically walking north, getting me into what looks to be one of the most isolated areas I’ve been to so far. We’re way off anywhere the Street View vehicle’s been, people, and about 23 km from the nearest town — Lima, MT, population 212 (and steadily declining).

Synth stuff for sale

Mon, 15 Jan 2024 23:01:11 -0500

I’m not really in business, but I do have extra PCBs and panels from fabrication orders sometimes, and sometimes some other synth-related stuff.

The following items are available. Inventory numbers are not necessarily up to date. Sales are to US residents only — sorry, just too much hassle otherwise! Shipping amounts are for purchase of a single item, quantity 1; shipping for multiple items or larger quantities will be more than that (but less per item). See below for how to order.

LMNC builds AO

Sun, 14 Jan 2024 16:07:02 -0500

A new video from Look Mum No Computer includes a brief glimpse of my Gate Grinder module, followed about 10 seconds later by footage of building two Dual Quantizers. You can see them in use afterward as he makes music with his synth.

AO Dual Quantizers (left) in LMNC’s PortaKosmo synth

previous:	AND video
next:	Nuclear Decay meets autunite

AND video

Sun, 14 Jan 2024 15:15:41 -0500

Add Noise Drum video!

https://diode.zone/w/5uob3TnU9R7dDQK4VKM25v

(I’ll be posting new videos first at diode.zone, an ActivityPub federated PeerTube instance, then later at YouTube.)

previous:	Nuclear decay
next:	LMNC builds AO

Nuclear decay

Thu, 11 Jan 2024 21:54:25 -0500

About three years ago, TimMJN of the LMNC Discourse made a module out of a cheap Geiger counter. Whenever the counter detects a particle the module produces a time-decaying control voltage. Nuclear decay, get it? Kind of a poor man’s version of Nervous Squirrel’s uranium-driven Random Voltage Generator.

Recently I decided I wanted to build a module like Tim’s too. I mean, I used to work in nuclear and particle physics research, I felt like I kind of really should.

Ringer [SB]

Mon, 08 Jan 2024 22:52:17 -0500

This is a Kosmo format module inspired by the Befaco A*B+C. It can do four quadrant multiplication as well as serve as a VCA or an attenuverting 2 channel mixer.

Ringer and A*B+C both are based on the AD633 chip, but other than that the circuit designs are entirely different: Ringer uses a different attenuverter circuit, and includes offset trimmers not included in the Befaco module.

Ringer

Mon, 08 Jan 2024 22:02:29 -0500

This is Ringer:

Ringer module

It’s a Kosmo format four quadrant multiplier, basically. That means it can take two voltages as input and multiply them together for the output. A VCA does that, sort of, but it takes a bipolar signal and multiplies it by a control voltage that has to be non negative — if you give it a negative CV it’ll just treat it as zero. That means it’s a two quadrant multiplier. A four quadrant multiplier can multiply one bipolar signal by another: Both signals can be either positive or negative, and it will multiply them.

Add Noise Drum [SB]

Fri, 05 Jan 2024 17:33:10 -0500

This is a drum module that produces percussive sounds based on tones and noise, suitable for kicks, toms, wood blocks, hi hats, snares, and so on. The tone section (left half of the panel) is based on the Barton Musical Circuits Analog Drum and the same PCBs are used in my Kosmo size, modified Analog Drum.

Barton Analog Drum [B]

Fri, 05 Jan 2024 17:33:10 -0500

This is a Kosmo size, modified version of the Barton Musical Circuits Analog Drum. Modifications include a trigger sensitivity control and an input jack to substitute an different audio signal for the internal VCO. It’s built using half the PCBs used in my Add Noise Drum.

Add Noise Drum

Wed, 03 Jan 2024 11:05:04 -0500

I had a bit of a problem with my last PCB/panel fabrication order:

Not how I designed it

It looked fine in both the KiCad Gerber viewer and the fabricator’s web-based Gerber viewer. Turns out there was a bug in their engineers’ software. They’re redoing the panels.

But that’s why this post ~~contains~~ contained no photos of my new module. [Update: Now it does.]

Earthwalk Day 709 (1 January 2024), 7132 km: 2023 and beyond

Mon, 01 Jan 2024 23:08:03 -0500

Here’s today’s walk:

Walking route, 1 Jan 2024

I’m been banging on the spreadsheet trying to get it to properly deal with the new year as well as the two previous. I think it’s right now. It tells me December was a pretty good month — down in steps per day and distance per day from November, but decidedly up from last December. It helps that I went for another bike ride on one of the warmest days of last month — which was Christmas. That time I did deliberately set out to cover distance, in particular more than 40 km, and I think that’s the first time I’ve done that distance in one ride in many years.

A theremin for Christmas

Sun, 31 Dec 2023 08:13:42 -0500

I got a theremin for Christmas! Okay, I got it from me. Also, two days after Christmas. Still, it’s the thought that counts.

It’s the OpenTheremin V4.5 from GaudiLabs.

It’s not for theremin purists: It produces its sound digitally, not the old fashioned way. But it’s still controlled by capacitive sensing with two antennas, like the 1919 original. Output jacks give you not only sound, but two control voltages and a gate, so you can use it as a synth controller.

Books of 2023

Sat, 30 Dec 2023 21:21:00 -0500

It says here I finished reading 44 (non comic) books in 2023. Don’t get the wrong idea: They were mostly lightweight fantasy or science fiction. I haven’t been much in the mood for nonfiction lately, or Weighty Novels, and it’s been an eternity since I’ve been in the mood for short stories.

Books I started and did not finish reading in 2023 include the one I’m working on now. (Christopher Moore’s Lamb, a reread.) Other than that, a small number I stopped reading either because I just didn’t like them (and there should have been a less small number of them; for instance, why I didn’t bail out of D. A. Holdsworth’s How To Buy a Planet early on I don’t know — I certainly wish I had), or because they were not about what I thought they’d be about and I wasn’t interested in what they were about. Or in one case, there were a very promising first few chapters of an on-sale novel I downloaded as a free sample, only to find I hadn’t read it fast enough and the sale price had expired in the meantime. I’ll wait until it’s on sale again.

Multiply perfect

Fri, 22 Dec 2023 21:08:00 -0500

There’s a fun mathematics video event called Clopen Mic Night and the December edition is available, for a limited time, for viewing on YouTube. One of the “acts” was Luna talking about multiperfect numbers — afterward I did some exploring of it myself. And I found this number: 518,666,803,200. (Not that I was the first to find it, of course, but I did find it on my own.)

A perfect number sometimes is defined as a number whose aliquot factors — the ones not including the number itself — sum to that number. For instance:

Earthwalk Day 699 (22 December 2023), 7030 km

Fri, 22 Dec 2023 17:45:22 -0500

Making my virtual way north through Idaho. I skirted Malad City and Arimo, then marched right down Center Street right through McCammon. Past that, according to Google Maps, I went parallel to the rather one dimensional Indian Rocks State Park, but according to this site the park closed 40 years ago. Today I’m just east of Inkom, a city, it says here, whose population in 2010 was 854 and which is home to the world’s smallest airport.

Attenuverters two

Tue, 19 Dec 2023 19:50:55 -0500

Here’s an attenuverter:

Simple attenuverter

You find this design in lots of places. When the wiper is fully counterclockwise, it’s equivalent to this:

Equivalent circuit with wiper CCW

R3 doesn’t matter, it doesn’t change the input voltage, so we can ignore it (aside from the fact it draws a little current, but it doesn’t change the output). So it’s just an inverting amplifier with gain equal to -1 times the ratio of R2 to R1, which is -1: The output voltage is minus the input voltage. Which is one thing you (normally) want from an attenuverter.

A DIY format

Sat, 16 Dec 2023 10:50:32 -0500

Kosmo, again, is mainly a DIY format. There is nothing stopping anyone from making and selling pre-assembled Kosmo modules, but hardly anyone ever has so far. LMNC sells bare PCBs and front panels, as do some other Kosmo builders, but you have to source the components and assemble the modules yourself (or hire someone else to).

Board and panel set for an LMNC Kosmo module

Other modules are available only as design files: You can upload these to a PCB fabrication company and get your PCBs and front panels that way. Many Kosmo builders eschew PCBs in favor of building on stripboard (Veroboard) or other type of prototyping board, and many stripboard designs are publicly available.

Eurorack and its discontents

Sat, 16 Dec 2023 10:50:32 -0500

Eurorack is by far the most familiar format. The height is 128.5 mm. Widths are multiples of 1 HP = 0.2 inches = 5.08 mm. Patching jacks are 3.5 mm phone jacks.

Most other formats are physically larger than this. The MOTM format, for instance, has height 5U (8.75 inches) and minimum width 1U (1.75 inches). Patch jacks are 1/4" phone jacks.

Smaller height doesn’t mean a smaller system if there is a corresponding increase in module width. But in the Eurorack community, there is a prevalent attitude that narrower is better. Almost the first thing people want to know about a Eurorack module is, how narrow is it? At least one company specializes in modules that are the minimum feasible width of 2 HP. The smaller patching jacks facilitate making the modules smaller; so do use of small knobs, or even no knobs at all — just knurled potentiometer shafts — and close spacing of jacks, pots, and switches.

Kosmo and Eurorack

Sat, 16 Dec 2023 10:50:32 -0500

Due to their being electrically the same (aside from Eurorack’s rarely used +5 V rail and CV and gate distribution), Kosmo and Eurorack modules work well together. Both can be powered from the same power supply using the same ribbon cables. Signals produced by one can be used unmodified by the other. The one wrinkle is the patch cord sizes, but 1/4" to 3.5 mm adapters are available, or you can use a “jumbler” module with both types of jacks connected together to go from one standard to the other.

Kosmo resources

Sat, 16 Dec 2023 10:50:32 -0500

Some Kosmo resources:

Look Mum No Computer
Website for Sam Battle, a.k.a. LMNC, including:
- Building your own modular synth
- Projects including information on various Kosmo modules
- Store including PCB and panel sets for LMNC’s Kosmo modules
LMNC Discourse
Friendly discussion group for synth builders, with an emphasis on Kosmo (but all formats welcome). Some notable topics:
- Discourse FAQ/Guidelines: Read before posting
- Glossary: Definitions of some synth terms
- List of LMNC modules and synth projects: Links to store, project page, and Discourse discussions
- General advice for troubleshooting a module and asking for help: What to do when your build isn’t working
- Kosmo Specification: Informal definitions of what makes a module Kosmo
Kosmodular Grid
A listing of Kosmo module designs available from various makers. Currently this is out of date and may soon be replaced with:
Kosmo modules wiki
Under construction, intended to be a more complete and up to date listing of Kosmo modules

Kosmo builders’ sites:

Previous: Kosmo and Eurorack
Up: Kosmo format modular synthesizers

Kosmo standard

Sat, 16 Dec 2023 10:50:32 -0500

LMNC could have used MOTM or one of the other larger formats, but chose to create something new. He was building his own modules and had access to 20 cm wide sheet aluminum for panels, so chose that as the height. Staying metric, he made the widths multiples of 5 cm. He liked 1/4" patch cords better than 3.5 mm so used 1/4" jacks. For ease of interoperability with Eurorack and adaptation of Eurorack circuit designs, he kept Eurorack’s electrical standards, more or less. Eurorack power voltages are ±12 V and +5 V, connected via 16-conductor ribbon cables to 16-pin headers, or one can use 10-conductor cables and 10-pin headers to get only ±12 V. In modern Eurorack module design 10-pin headers and non-use of the 5 V rail is nearly ubiquitous. In Kosmo only the 10-pin power header option is specified — there is no 5 V rail. Aside from that, Kosmo uses the same supply voltages and compatible signal voltages and widths as Eurorack.

What is a modular synthesizer format?

Sat, 16 Dec 2023 10:50:32 -0500

If you are going to put multiple synth modules in the same case, or at least the same row of the same case, then they all will need to be the same physical height.
Widths can vary, but it can be beneficial to have all module widths be multiples of some fundamental width.
If the modules are to connect to the same power supply, then obviously they need to be designed to use the same supply voltages, and to use compatible supply voltage connectors.
If the modules are to be connected to one another via patch cords, they need to be designed to use the same type of patching connectors.
If the modules are to send signals to one another, they need to be designed to use compatible voltage levels and time widths for their signals.

A modular synthesizer format typically specifies a standard height, set of widths, power supply voltages, power supply connector, patch cable jack type, and signal levels and widths.

Earthwalk Day 688 (11 December 2023), 6937 km: Idaho

Mon, 11 Dec 2023 21:04:48 -0500

I accidentally my longest bike ride in… decades? On Saturday. In December! It got up to around 13°C (57°F). Sounds fairly warm but there was some wind and I decided to wear my mittens — a decision I do not at all regret.

I didn’t set out to go so far, just did a modification of a route I’ve done before, and I didn’t realize how far I’d gone until I checked my log after the ride. It was 38.5 km, which just edges out my 38.3 km ride on 8 July 2018.

Funque Mod G.E.A.R. Sequencer

Mon, 11 Dec 2023 19:35:57 -0500

This is Christian Bloch’s Eurorack version of my Kosmo G.E.A.R. sequencer; Christian kindly sent me one.

Haraldswerk Modulation Sequencer

Mon, 11 Dec 2023 12:17:11 -0500

Modulation Sequencer on Haraldswerk site

Christian Bloch did a Eurorack version of this module and sent me a board and panel.

Analog Output Noise Bells

Mon, 11 Dec 2023 12:15:15 -0500

This is a percussion and drone synth module based on ideas presented in the 2015 Hackaday article “Logic noise: More CMOS cowbell!” by Elliot Williams.

Git repo

LMNC 3xSplashback

Mon, 11 Dec 2023 12:13:36 -0500

This, oddly, is the only LMNC board and panel set I’ve built: The #2399 3xSplashback reverb. I added the toggle switch (discussed on the project page) to give wet-only output.

2399 3xSplashback

Cory Torpin Switched Multiple

Mon, 11 Dec 2023 12:08:51 -0500

Switched Multiple designed by Cory Torpin.

Git repo

Cory Torpin Sequential Switch

Mon, 11 Dec 2023 12:08:36 -0500

This is a sequential switch designed by Cory Torpin.

Git repo

Mikrokosmos

Mon, 11 Dec 2023 12:07:54 -0500

This was my first Kosmo format module: An adaptation of the Music Thing Modular Mikrophonie.

Git repo, superseded by Mikrokosmos II

Cory Torpin K25 LFO

Mon, 11 Dec 2023 11:55:58 -0500

This is a simple LFO module designed by Cory Torpin, from a set of several 25 mm wide modules.

Git repo

Analog Output Megamodule

Mon, 11 Dec 2023 11:54:40 -0500

This is a rather crazy project, half synth DIY, half circuit bending. I took the PCB from a toy voice changing megaphone and turned it into a module. This involved adding a comparable number of new components on a protoboard, and bending the original PCB to add variable speed/pitch (with voltage control) and feedback.

Git repo

Analog Output Dual Quantizer

Mon, 11 Dec 2023 11:53:59 -0500

A dual quantizer module. It’s based on my dac/ino Nano and DAC board.

Git repo

Analog Output Positivizer

Mon, 11 Dec 2023 11:53:50 -0500

This was a quickly put together little module to take ±5 V control signals and rescale/offset them to 0 to 5 V. A very simple circuit and I did it on protoboard so there isn’t a Git repo.

Analog Output Expression Pedal

Mon, 11 Dec 2023 11:53:31 -0500

Expression pedal interface synth module.

Designed for use with an M-Audio EX-P pedal but should be more generally usable with suitable tweaks. With no CV input, pedal controls an output CV varying from 0 to 10V with range pot all the way up. With CV input, pedal controls an attenuated version at output. Use range pot to adjust output range.

With no pedal plugged in, it behaves as if there were a pedal completely down, so range pot gives 0 to 10V voltage source with no CV input, or attenuated CV with CV input.

LMNC/AO 8 Step Sequencer

Mon, 11 Dec 2023 11:53:01 -0500

This is my adaptation of LMNC’s 8 Step Sequencer Keyboard. Main modifications are:

Added rotary switch to select sequence length or pattern
Added switches to turn off outputs for steps
Added Zero gate input
Added “Reverse time” switch (which exchanges the roles of the Forward and Backward gate inputs)
Software change allows you to hold down multiple buttons and only those steps will be used

Git repo

NLC Sloth Chaos

Mon, 11 Dec 2023 11:52:37 -0500

I put the NLC circuit board behind a Kosmo front panel.

Sloth Chaos on ModularGrid

Analog Output Gate Grinder

Mon, 11 Dec 2023 11:51:36 -0500

This was the first module I ever designed the circuit for. It generates clocks and acts on triggers and gates (called “signals” generally herein).

Signals come from three sources. There is a jack for an external CV input (±12V). There is a pushbutton for manually created gates. Finally, there is an internal clock to produce a stream of square gates.

If the Resize On/Off switch is set to Off, the OR of these three signal sources is sent to the Out jack. Otherwise the rising edges are used to trigger a one-shot whose output width is controlled by the Resize Narrow/Wide switch and the Width knob, and the resulting signals are sent to Out. Output widths can vary from about a few milliseconds to about 5 seconds.

Tip Top µZeus

Mon, 11 Dec 2023 11:31:11 -0500

µZeus on ModularGrid

This is the one synth module I’ve bought assembled.

GMSN! Pure VCA

Mon, 11 Dec 2023 11:30:50 -0500

Pure VCA on ModularGrid

MFOS State Variable Filter

Mon, 11 Dec 2023 11:30:11 -0500

This is one of Ray Wilson’s “Oldie But Goodie” modules. As an exercise in learning to use KiCad I drew up a Eurorack-friendly PCB pair and a front panel and got them fabbed, my first synth PCBs and FR4 panels.

Git repo

AI Synthesis Mixer

Mon, 11 Dec 2023 11:29:51 -0500

Mixer on ModularGrid

Żłob Modular MiniAtt

Mon, 11 Dec 2023 11:29:01 -0500

MiniAtt on ModularGrid

horstronic. Buffmult

Mon, 11 Dec 2023 11:24:02 -0500

Buffmult on ModularGrid

PMFoundations Ring

Mon, 11 Dec 2023 11:22:26 -0500

Ring on ModularGrid

Analog Output Reverb/Echo

Mon, 11 Dec 2023 11:19:45 -0500

This was my first DIY synth module, for certain values of DIY. I took a cheap PT2399-based delay module, swapped out the speed resistor for a pot, added a Eurorack power header, and put it behind a homemade panel.

NLC Timbre

Mon, 11 Dec 2023 11:15:18 -0500

Timbre on ModularGrid

Barton FM Drum

Mon, 11 Dec 2023 11:14:46 -0500

FM Drum on ModularGrid

The panel is an undecorated one from Barton with a laminated paper overlay I designed.

Barton Analog Drum

Mon, 11 Dec 2023 11:14:39 -0500

Analog Drum on ModularGrid

The panel is an undecorated one from Barton with a laminated paper overlay I designed.

Befaco Even VCO

Mon, 11 Dec 2023 11:06:31 -0500

Even VCO on ModularGrid

AI Synthesis Looping ADSR

Mon, 11 Dec 2023 11:06:05 -0500

Looping ADSR on ModularGrid

Earthwalk Day 678 (1 December 2023), 6826 km: I've returned to Syracuse!

Fri, 01 Dec 2023 21:12:39 -0500

See?

A map showing my progress is here, a spreadsheet with progress detail is here, and a Google Earth KMZ file is in this Google Drive folder. Present coordinates: 41.097°N, 112.007°W.

previous:	Earthwalk Day 673 (26 November 2023), 6789 km: Utah State Capitol
next:	Earthwalk Day 688 (11 December 2023), 6937 km: Idaho

Earthwalk Day 673 (26 November 2023), 6789 km: Utah State Capitol

Sun, 26 Nov 2023 19:46:20 -0500

Here, look at this. Does this look like a state capitol to you?

Utah State Capitol

Yeah, it does to me. I mean it screams State Capitol. State Capitol of Utah, in fact, located in Salt Lake City, completed in 1916.

I arrived there, virtually, today, bringing an end to Leg 24.

I’ve been to SLC once in real life — where by “been to” I mean “spent an hour or so in the bus station, en route from Banff National Park to Denver”, back in 1981. And at one time I was regularly sending money to SLC, in exchange for their sending microfilms from the Mormon church’s Family History Library to where I was. (The Mormons, for theological reasons I have no interest in getting into, have a great deal of interest in genealogy, and the Family History Library in SLC is the largest genealogical library in the world. )

Instant reaction: Doctor Who, The Star Beast [no spoilers to speak of]

Sat, 25 Nov 2023 23:23:03 -0500

So let’s say this: I truly liked some of what Chris Chibnall did in his stint as Doctor Who showrunner — starting with his hiring of Jodie Whittaker, who was a very good Doctor indeed. And I include also his “Timeless Child” story line, which, shall we say, has its detractors. But I liked it. With a show this old it needs to be shaken up good and hard once in a while. The Timeless Child gives all sorts of potential for interesting new stories. And it brought us Jo Martin, who also was a very good Doctor indeed. I’d watch the heck out of a Fugitive Doctor spinoff series, if it had the right showrunner.

primeclassify

Mon, 13 Nov 2023 21:34:36 -0500

That business with the beeping machine pushed me down a rabbit hole over the weekend, and when I came out I was hanging on to a brand new Python library of functions for checking what classes a prime number belongs to.

It’s on PyPi here, and the source code is on GitLab here.

Note it doesn’t find primes in these categories, it checks whether your prime is in them. You can’t use it to find the next, larger-than-the-largest-known Mersenne prime, for instance. You give each function a prime number and it returns False if it’s not in that category or True (or in some cases some other non-False value) if it is — assuming it’s prime, which it doesn’t check. (After all, if you’re checking a number against all the categories, it’d be dumb to have each function check the primality of the same number.) If it doesn’t know whether it belongs in that category or not, it returns None.

Earthwalk Day 657 (10 November 2023), 6630 km

Fri, 10 Nov 2023 21:51:42 -0500

Very little to say about the past two weeks. Pushing west across Utah. A lot of wide open not very much. Duchesne was the one real town I went through. It says “Strawberry” near my present location on the map, but whatever’s in Strawberry, it hasn’t been enough to get the Street View car to turn off Route 40.

Steps and distances per day in October were pretty close to typical. This month, in real life, it’s getting colder, we had snow on 1 November, and it’s been rainy a lot otherwise. I got two rides in, one in 10°C (50°F) temperature I thought I wouldn’t need mittens for, but my fingers were so numb by the time I finished, I had a hard time getting my helmet off.

Prime time

Thu, 09 Nov 2023 07:20:01 -0500

On the Fediverse, mcc posted:

A machine that beeps once every time the current UTC timestamp is a prime number

which led to a number of responses; one was this from Christian Lawson-Perfect. I’m pretty sure the linked website pre-existed but the date-tracking functionality was newly added. Unfortunately in my browser the beeping doesn’t work.

A few thoughts. First, to explain, the Unix time, which is almost certainly used by your computer or phone, is the number of non-leap seconds since 00:00:00 UTC on Thursday, 1 January 1970. Right now it’s 1699532940, which obviously is not a prime, though 23 seconds earlier, 1699532917 was.

Analog Drum breadboard notes

Sun, 05 Nov 2023 08:33:59 -0400

I made a Barton Analog Drum in Eurorack a few years ago, and I currently have one on breadboard. I’ve found a few things I want to change.

I noticed in my Eurorack module if I tried triggering with a gate it sometimes would trigger on both the rising and falling edges. I never chased down the reason but I suspect it was that there was some ringing on the falling edge, taking it up above the comparator threshold again. That threshold is pretty low, about 120 mV from a 100k/1k voltage divider on +12 V. Changing that to a less extreme ratio might help, or better yet changing it to a pot for an adjustable threshold.

Whistle while you noise

Sat, 04 Nov 2023 00:11:19 -0400

[Revised 2023-11-17]

A couple years or so ago I built a Kosmo version of the MFOS Noise Cornucopia. Now I’m designing a module that needs white noise so I thought I’d just drop in the Noise Cornucopia source. I breadboarded it:

Noise source from Noise Cornucopia Rev. 1

And… it didn’t work. I mean it did generate noise, but it also output a faint tone, up very very roughly around 1 kHz I’d say. Almost a whistle. I’d never heard that from the module I built.

Slope

Mon, 30 Oct 2023 16:43:31 -0400

This is the Kassutronics Slope adapted to Kosmo format by Ben Rufenacht, with subsequent restyling and minor tweaks by me.

Git repo (for panel design)

Display and Slope

Mon, 30 Oct 2023 16:02:48 -0400

My summer building break is over (late, but it started late too). I’ve built, technically, two new modules, though one is hardly enough to merit the title.

Power Display

I’ve built one power display module (just a couple LEDs and test points) for each of my bus boards, but I decided to do a new version to replace at least one of them. This one adds a power header on the front panel — to make it easier to power modules that are being tested or undergoing troubleshooting.

Earthwalk Day 642 (26 October 2023), 6472 km: Utah

Thu, 26 Oct 2023 17:00:32 -0400

I’ve (virtually) parted company with US 40 and, indeed, with anything involving pavement apparently, and as of today am in Utah. My 17th state. I spent 54 days in Colorado. The nearest town is back in that state — Dinosaur, CO.

Where I really am, along the Loop the Lake trail, there are fungi:

Mushrooms

A map showing my progress is here, a spreadsheet with progress detail is here, and a Google Earth KMZ file is in this Google Drive folder. Present coordinates: 40.198°N, 109.093°W.

Less droopy YASH

Tue, 24 Oct 2023 20:17:21 -0400

I finally got around to modifying my YASH: 10 nF instead of 1 nF for the integration cap and 4.7 nF instead of 470 pF for the gate width cap. The former change makes the droop rate about 10x slower and the latter makes the integration gate 30 µs instead of 3 µs to compensate for the longer charging time. Originally, with a 1 V input signal, the output was drooping by about 150 mV over 10 seconds. With the new capacitor values I can still see a little droop on that time scale but it’s a big improvement over what it was. I updated the design files and docs at https://gitlab.com/rsholmes/yash.

Kosmodrome Phase 3

Tue, 24 Oct 2023 09:56:05 -0400

Kosmodrome Phase 2 is done. What about Phase 3?

There isn’t really so much of a need to formally define Kosmodrome Phase 3. Phase 1 was all about putting a basic synth together and Phase 2 was extending it in some fundamental ways. At this point, further expansion is mostly a matter of “this seems like an interesting module” or “hm, I need more of xxx”. More “these are things I want to do” than “this is an aspect that needs to be included”.

Earthwalk Day 636 (20 October 2023), 6410 km

Fri, 20 Oct 2023 18:24:58 -0400

I’m continuing to walk virtually along US Route 40, currently roughly in a southwest direction. Today’s position is fairly near a place called out on Google Maps as Elk Springs, but there doesn’t seem to be anything there other than a couple houses. Otherwise lots of scrub, not much else.

The last thing I passed through (earlier this week) that I’d regard as a populated place, however small, was the unincorporated community of Maybell, population 76 as of 2020. It has the platonic ideal (at least its exterior is) of a general store, complete with one Sinclair gas pump… and a Sinclair dinosaur. A small one, but appropriate considering I’m now about 13 km south of Dinosaur National Monument. Won’t be passing through the latter, unfortunately.

AC coupled square waves are less than obvious

Thu, 19 Oct 2023 23:41:30 -0400

Okay, this is about nothing of any practical importance I can think of, but I got interested in the subject, and arguably it’d be better posted at Mathematrec, but then I’d have to explain things like what a high pass filter is and so on, so it goes here.

This is about AC coupling. That’s when you use a capacitor in series after a signal source to remove its DC component, leaving only the oscillatory behavior around zero. Or rather, not just a capacitor. Think about it. If you connect a signal source on the left side of a cap, how does the right side know how to remove DC? Voltage, after all, is relative — it’s always measured relative to some other point, usually ground. The DC component is a constant voltage relative to ground. But how does that cap, which isn’t connected to ground, know what ground is? It doesn’t. So it can’t know how much DC to subtract.

Bathroom scope creep

Sun, 15 Oct 2023 13:05:55 -0400

Project: Bathroom improvements

Originally intended tasks:

Remove molding
Pull up old vinyl tiles
Evaluate and repair floor damage near toilet
Put down new vinyl tiles
Replace molding

Actual tasks:

Remove molding
Pull up old vinyl tiles
Pull up old underlayment
Remove vanity, sink, faucet
Buy new vanity, sink, faucet
Discover floor damage near toilet was much worse than expected
Remove toilet and flange
Bring in someone to cut out damaged subflooring and replace it
Put down new underlayment
Cut back underlayment near soil pipe after reading flange should go on subflooring
Buy new toilet and adapter flange
Try to install new flange, find it will not fit due to soil pipe corrosion
Try to get plumber to deal with flange, get put off for 10 days or so
Get plumber to agree to come take a look at it; instead plumber gets hospitalized with pneumonia
Get another plumber to come take a look at it; they say soil pipe needs fixing, requires licensed plumber, they refer me to one
Get licensed plumber to come take a look at it; they say they can do it but needs underlayment and vinyl up to soil pipe because flange should go on finished floor
Fill in underlayment near soil pipe
Put down new vinyl tiles
Get licensed plumber back to do the work. They:
- Grind down soil pipe to proper level
- Try three adapter flanges, first two are not satisfactory, third one fits around soil pipe so they cut away tile and wood around soil pipe
- Install new toilet
Modify vanity to account for non level floor and up-from-floor plumbing
Put new vanity in position
Belatedly remember the ceiling has needed repainting for years
Examine old molding and decide to replace it, will need to paint new molding
Belatedly decide to repaint walls
Paint ceiling
Paint walls
Mount faucet to sink
Install sink
Plumb faucet
Install and paint new molding
Caulk around tub
Paint trim
Buy and hang new curtains on new rods

Original time estimate:

2 afternoons

Earthwalk Day 622 (6 October 2023), 6245 km

Fri, 06 Oct 2023 19:50:34 -0400

I’m about a third of the way through Leg 24. I’m heading northwest away from Denver, just short of Steamboat Springs, close to Rocky Mountain National Park, where I hiked really, not virtually, for a few days back in 1981.

Last month was right in line with expectations, with steps and distances matching pretty closely to both the month before and a year ago. Only 5 bike rides, versus 8 the month before, but the distance was still respectable. I was out of town twice in one week, and that didn’t help the ride count.

Git and GitHub and GitLab for synth DIY people with better things to do than to understand git and GitHub and GitLab

Tue, 19 Sep 2023 14:43:34 -0400

Git is powerful. Git is fully featured. Git is a pain in the butt to understand.

You have better things to do than to understand git.

What git is: It’s a version control system. It allows you to save projects as they evolve, and you can go back to earlier versions if needed. It facilitates working on new features without messing up the older version, and collaboration between multiple people on the same project.

Earthwalk Day 604 (18 September 2023), 6006 km: Colorado State Capitol

Mon, 18 Sep 2023 19:15:27 -0400

And that’s it for Leg 23. I told you it wasn’t far. Then again, if you took a look at a map, you’d see the Colorado State Capitol in Denver is only 43 km from the Colorado Air and Space Port, and you would not be surprised I’m done already.

Colorado State Capitol, 1906

You can tell it’s a Capitol. In fact it resembles the US Capitol building. Intentionally, it says here. Except the US Capitol dome isn’t covered in gold leaf, and this one is. Nor does the interior of the US Capitol make use of Colorado Rose Onyx, because this one uses it. All of it. It says here.

Earthwalk Day 601 (15 September 2023), 5980 km: Colorado Air and Space Port

Fri, 15 Sep 2023 19:24:46 -0400

Leg 22 is done: I’ve arrived at the Colorado Air and Space Port (CASP).

First I had to arrive in Colorado. I did that only a couple of days after leaving Cheyenne, having spent 32 days in Wyoming. From there I headed south, to a point east of Denver.

CASP is… a general aviation airport. It has flying schools and clubs. It does not have a major rocket launching facility. Or a minor one. But in 2011 Colorado requested the airport be designated by the FAA as a spaceport, and the FAA agreed a mere seven years later. The intention was that it would become a facility for horizontally launched spaceplane operations — and maybe that will eventually happen; PD Aerospace and Dawn Aerospace, both working on spaceplanes, have some sorts of agreements with CASP to, maybe, do something at some point. Rather more concretely, Reaction Engines has built a test facility at CASP for technology to be used an an air-breathing rocket engine they’re developing.

Vactrol information

Fri, 15 Sep 2023 11:28:47 -0400

This is some information on commercially available vactrols, and on photoresistors (LDRs) which might potentially be used for making DIY vactrols.

For a wealth of technical information on LDRs and vactrols, see https://ka-electronics.com/images/pdf/Perkin_Elmer_Photocell_Vactrol_Catalog.pdf. (Note PerkinElmer is no longer in this business and the specific photocells discussed are no longer available. Xvive makes vactrols with the PE product numbers, see below.)

Xvive

Xvive vactrols — some of them — are available from SynthCube and Thonk. Datasheets for each type are available.

Here we go again

Fri, 08 Sep 2023 08:00:16 -0400

For reasons, I took a break from synth building for a few months. Some design work but no building. With (meteoroligical) fall here, it’s time to get back into it. So what’s up?

One of my top priorities: Modifying YASH. This sample and hold works okay, but the droop rate is pretty high. From the LF398 datasheet, it should improve more or less proportionally to the size of the integrating capacitor, so bumping that up from 1 nF to 10 nF should make it a lot better. But that also means it will take ten times as long to charge. So the cap in the trigger processor also needs to go up a factor of ten. The charging gate as it stands is only 3 µs; making that 30 µs should be fine, still too short to be audible.

Hub to Lab

Sat, 02 Sep 2023 23:43:06 -0400

I’m absolutely not a fan of the hype, inappropriate uses, bad designs, questionable ethics, and poor implementations characteristic of the recent surge in AI or LMM or whatever initials you want to call it by. I don’t want AI writing my blog (so I left Wordpress) or doing my web searching for me (so I’m very concerned about Google and Bing), and I certainly don’t want AI doing my coding — to the extent I do any coding anyway. Point is, when GitHub opens an account on the Fedi, where (at least in my home feed) I see all sorts of skepticism, antagonism, and hostility toward the AI fad, and proudly puts in their profile that they’re “AI powered”, I find that both sad and amusing, and it also brings home the idea that, yes, it really is time to abandon that platform too.

Earthwalk Day 586 (31 August 2023), 5795 km: Wyoming State Capitol

Thu, 31 Aug 2023 22:11:38 -0400

Today’s bike ride brought me to the end of Leg 21: The Wyoming State Capitol in Cheyenne. Cheyenne was named the temporary state capital in 7 May 1869. Maybe they’ll make it permanent someday. Neil Diamond lived in Cheyenne as a child.

Construction on the capitol began in 1886, four years before Wyoming became a state. It took that long to finish it, so that was some good planning, I suppose.

Chandrayaan-3 lands

Wed, 23 Aug 2023 09:02:31 -0400

Back in 2017 when I started my MoonWalk, I expected to consider modifying my route to add in several landings taking place after my start. Turns out I added only one: CSNA’s (China) Chang-e 5.

In April 2019 SpaceIL’s (Israel) Beresheet crashed.

In September 2019 ISRO’s (India) Chandrayaan-2’s Vikram lander crashed.

Those were the only attempts during the MoonWalk other than CSNA’s Chang-e 4 on the far side, successful but too far to walk to. Others that had been anticipated were delayed.

Earthwalk Day 573 (18 August 2023), 5632 km

Fri, 18 Aug 2023 19:07:33 -0400

A quick update. I’ve been in Wyoming a little over two weeks, heading south. I’ve done four bike rides in that time so am making good time, and am about to enter Fort Laramie. That’s about it.

A map showing my progress is here, a spreadsheet with progress detail is here, and a Google Earth KMZ file is in this Google Drive folder. Present coordinates: 42.259°N, 104.515°W.

previous:	Earthwalk Day 556 (1 August 2023), 5419 km: Wyoming
next:	Chandrayaan-3 lands

Non-extendable knight's paths

Thu, 10 Aug 2023 19:32:38 -0400

(This is a consolidation, revision, and correction of several Mathematrec blog posts.)

8x8 board

On the Fediverse, @sam_hartburn@mathstodon.xyz asks:

What’s the shortest sequence of knight’s moves you can make on a chessboard such that the path is blocked at both ends (i.e. from either end of the sequence there are no squares you can move to that you haven’t already landed on)?

and provides a candidate path, one with 10 positions linked by 9 moves from the starting square to the ending one.

Non-extendable knight's paths, part 4

Tue, 08 Aug 2023 13:01:44 -0400

Note: There are errors here, see revised article for corrected analysis.

The same approach as was used for the 5x5 torus can apply to other tori. For each possible offset between the termini, count up the number of distinct neighbors and the number of neighbor clusters. Their sum is a lower limit on the minimal number of moves for a non-extendable path. If a cluster doesn’t have a Hamiltonian path, though, extra moves are needed; likewise if a single intermediate position isn’t enough to get from one cluster to another. In the 5x5 case with a knight’s move offset there are 11 neighbors and two clusters with Hamiltonian paths, so the limit is 13 moves (14 positions), and paths of that length do exist.

Non-extendable knight's paths, part 3

Mon, 07 Aug 2023 18:02:25 -0400

Note: There are errors here, see revised article for corrected analysis.

How about non-extendable paths on toroidal boards?

It’s easy enough to modify my script to do that. Change two lines. Boom. What’s not so easy is running the modified script, because it takes a lot longer. Analyzing a 3x3 torus takes about 40 seconds, versus 0.2 seconds for the ordinary 3x3 board. 4x4? Takes more than two hours. Granted, that’s on my computer, which is not the fastest in the world, and it’s a Python script, and Python is not especially fast. Still. A while.

Non-extendable knight's paths, part 2

Sat, 05 Aug 2023 08:44:47 -0400

Thinking about it some more, I believe all the ingredients are there to prove the minimum on an infinite board is 23 moves, or 24 positions.

If the termini are adjacent, we must reach 17 positions from the start. 12 positions are in two 6-cycles, so clearly we need 12 moves to reach them plus 1 move to get from one cycle to the other. There are four more positions that require 2 moves each to reach. (Or one could be reached in 1 move from the start position, but then you need 2 moves to reach the first 6-cycle.) 1 more move is required to reach the end. So we need at least 12+1+2×4+1=22 moves. But the termini are on opposite color squares, so the number of moves must be odd, so 23 is the minimum.

Non-extendable knight's paths

Thu, 03 Aug 2023 03:12:10 -0400

8x8 board

On the Fediverse, @sam_hartburn@mathstodon.xyz asks:

What’s the shortest sequence of knight’s moves you can make on a chessboard such that the path is blocked at both ends (i.e. from either end of the sequence there are no squares you can move to that you haven’t already landed on)?

and provides a candidate path, one with 10 positions linked by 9 moves from the starting square to the ending one.

Earthwalk Day 556 (1 August 2023), 5419 km: Wyoming

Tue, 01 Aug 2023 20:58:17 -0400

As mentioned previously, between rain, injury, AQI, and a week on the ATM, July pretty much sucked for number of bike rides (3), average distance per day, and average number of steps. Maybe August will be better. It’s starting better: I did a bike ride today. 29 km, well above the 5 km I needed to cross my next boundary. After 39 days in South Dakota this entry, and a total of 80 days in that state, I’ve crossed over into Wyoming, heading south on US Route 85.

Earthwalk Day 550 (26 July 2023), 5358 km: Sanford Underground Research Facility

Wed, 26 Jul 2023 20:20:59 -0400

It’s another of those substandard months. A couple days off due to rain. Then I twisted my foot and had to take more time off. Recovery came just in time for another AQI spike. Now I’m spending a week in Massachusetts with the American Travelling Morrice which leaves me with limited time for walking (and my bike’s back in Syracuse), and no, I don’t wear the pedometer while I’m dancing.

An index for MFOS

Mon, 17 Jul 2023 21:42:35 -0400

If you’re into synth DIY you have to know about Music From Outer Space. Ray Wilson ran that site for many years, posting his circuit designs and PCB layouts with BOMs and copious explanations, everything you need to know to build your own synth, freely available — you could buy PCBs from him but you could also just etch your own from the graphics he supplied. Wilson unfortunately died around 2016, I think, and since then the site’s been kept up by SynthCube. But they haven’t really changed anything; it’s pretty much the way Wilson left it.

MFOS index

Mon, 17 Jul 2023 18:52:34 -0400

The Music From Outer Space site has lots of great information, but I really can’t stand the frames and PHP navigation. This is a simple index directly to the Synth-DIY pages.

Analog Synthesizer Modules

CD Sales

ELECTROLUMINESCENCE

Electronic Components

Guitar Projects

Envelope Follower Filter
- Home
- Schematics
- Parts List
- PCB Info
- Case Drawings
- Wiring
Fuzz Tone
Guitar to Gate Convertor
SUB-COMMANDER Guitar Synth

Hot Tips

LO-FI Noise Boxes

Alien Screamer
Echo Rockit
Mini-Mixer 1W Amp
NOISE TOASTER
Synth-DIY Experimenter Board
- Home
- Oscillators
- VCF
- VCA
- LFO
- AR Gen.
- White Noise
- Full PC Board
- Parts Lists
- Ideas…
Weird Sound Generator
- Home
- Schematics
- Case Wiring
- Part List
- PC Board
- Troubleshoot
- Sounds
- Pics
- Mods

MFOS Apparel

MFOS In The Classroom

MFOS Oldies But Goodies

Mechanical Components

Power Supplies

Sequencers

Single-Board Analog Synths

Sound Lab Mini-Synth MARK II
- Home
- Schems
- Panel and Wiring
- BOM
- PCB
- Build Notes
- Mods
- New 17 x 7 Inch Panel
Sound Lab ULTIMATE
- Home
- Schematics
- Panel Wiring
- Parts List
- PCB Info
- Pictures
- Mods
- Troubleshooting
ULTIMATE EXPANDER

Sound Lab Mini-Synth

Sound Lab Mini-Synth
- Home
- Schematics
- Panel Wiring
- Part List
- PC Board
- Troubleshoot
- Sounds
Sound Lab Mini-Synth Extras
Sound Lab Mini-Synth PLUS

Synth-DIY 101

The Cave (Very Old Designs)

Tools and Calibrators

Vocoder

MFOS 12 Channel Vocoder

Building a Mutable Instruments Module Tester

Sat, 15 Jul 2023 12:04:24 -0400

The Mutable Instruments Module Tester is a highly recommended tool for anyone doing more than occasional testing or troubleshooting of synth modules. It provides test signals including clocks, gates, CVs, and audio tones, and diagnostics such as frequency measurement. The combination of CVs alternating between two octaves and frequency ratio measured in cents makes calibrating VCOs easy; it’s almost worthwhile just for that.

There are two versions of the PCB, v0.1 and v0.2. The main differences are the former uses a 12 VAC wall wart while the latter uses an easier to obtain 15 VDC wall wart, and the former uses Earthenvar jacks while the latter uses Thonkiconns, which again are easier to get.

I like big knobs and I cannot lie

Tue, 11 Jul 2023 14:11:34 -0400

2HP Eurorack modules with knobless pots you need tweezers to work? Puhlease.

Gimme some mil spec knobs.

(From here: https://www.product-lifecycle-management.com/download/MIL-STD-1472F.pdf.)

… Okay, fine, a modular synth is not a nuclear submarine. Still, to my mind, a synth knob isn’t a setup parameter; it’s a performance control. You don’t just set up a patch to get some particular sound, press record, play some notes on the keyboard, and stop recording. You use those knobs as part of playing the synth, morphing and evolving and mutating the sound as you go. But you can’t do that well unless you have a knob per function, one you can find easily and grab onto easily and turn smoothly and continuously, maybe with one hand while turning the next knob over with the other hand, without bumping into other knobs or your other hand or anything else that’ll prevent that smooth and continuous motion.

Blog tuning in Hugo

Mon, 10 Jul 2023 12:02:52 -0400

I’ve been trying to get the blogs set up in a reasonable way. The most reasonable way would be to have separate domains for each: doctroid.xyz, analogoutput.xyz, and so on, or at least separate subdomains: doctroid.richholmes.xyz, analogoutput.richholmes.xyz, and so on. But I know the former and I think the latter would cost more than I want to pay with the hosting service I want to use, so I’m just putting them at richholmes.xyz/doctroid, richholmes.xyz/analogoutput, and so on.

I, I, I, I, I...

Sat, 08 Jul 2023 13:01:26 -0400

This morning I found myself typing the phrase “reminded about it if it is in progress” and noticed the five consecutive two letter words starting with “i”. At first I thought I couldn’t improve on that. Eventually, though:

Me informing my friend Isabel of my intent to participate in an event provided it takes place in a particular Romanian commune:

“I’m in it, Iz, if it is in Ip.”

previous:	Here we are again
next:	Blog tuning in Hugo

Earthwalk Day 531 (7 July 2023), 5179 km

Fri, 07 Jul 2023 20:26:43 -0400

It’s July, so I’ve gotten through a not particularly great month. I did end up with more than 10 km average distance per day, just slightly less than May, but distinctly worse than June 2022. And that was because of 5 bike rides, but I had more than the usual number of non-walking days, so my average steps per day was way down. Partly that was due to rainy weather, in contrast to May — in fact we had two days in June each of which had more rain than the entire month of May. And partly that was due to two spikes in the Air Quality Index, thanks to wildfires in Quebec. (We had another very brief spike this week, from about 11 pm on July 4 to 3 am on July 5. Guess what caused that.)

Here we are again

Fri, 07 Jul 2023 16:39:46 -0400

Well. I’m trying something else for my blogs, again.

I found some faults with WriteFreely and write.as. For one thing I could not get ActivityPub federation to work properly — that is, it worked more or less correctly on the writing.exchange Mastodon server, but on vmst.io and mastodon.social I could follow my blogs but new content simply did not appear in my Home feed. For another thing, I use MathJax, especially on my Mathematrec blog, but in WriteFreely it’s basically impossible to proofread MathJax — because it doesn’t render it until you publish.

Here we are again

Fri, 07 Jul 2023 16:39:46 -0400

Well. I’m trying something else for my blogs, again.

Here we are again

Fri, 07 Jul 2023 16:39:46 -0400

Well. I’m trying something else for my blogs, again.

I found some faults with WriteFreely and write.as. For one thing I could not get ActivityPub federation to work properly — that is, it worked more or less correctly on the writing.exchange Mastodon server, but on vmst.io and mastodon.social I could follow my blogs but new content simply did not appear in my Home feed. For another thing, I use MathJax, but in WriteFreely it’s basically impossible to proofread MathJax — because it doesn’t render it until you publish.

Here we are again

Fri, 07 Jul 2023 16:39:46 -0400

Well. I’m trying something else for my blogs, again.

p2 polynomials Pascaled

Tue, 04 Jul 2023 14:34:59 +0000

I’ve now watched that 3Blue1Brown video and it explains how the Moser circle problem’s solution for $l n$ points is just the sum of the first 5 numbers in the $l n^{th}$ row of Pascal’s triangle, or $l R(n,5) = \sum_{i=0}^{4}{{n}\choose{i}}$, and how this explains why the first five numbers as well as the tenth one are powers of 2, since the $l n^{th}$ row of Pascal’s triangle sums to $l 2^n$. It doesn’t talk about more general p2 polynomials, but it’s immediately apparent the sequence generated by $l p2(m)$ is the sums of the first $l m$ numbers in each row, or $l R(n,m) = \sum_{i=0}^{m-1}{{n}\choose{i}}$. Hence entry $l 2m-1$ (counting from 0) is also a power of 2.

A line and a fractal and some miscellaneous points

Sun, 02 Jul 2023 23:33:13 +0000

I’m still thinking about $l (n-1)^{th}$ degree polynomials that generate the first $l n$ powers of 2 at the start. Which is rather a mouthful so I’m just going to call them p2 polynomials from here on. For instance, $l p2(5) = \frac{1}{24}(n^4-2n^3+11m^2+14m+24)$ generates the sequence 1, 2, 4, 8, 16, 31, 57, 99…

(By the way, this series of posts originally was prompted in part by this recent video by 3Blue1Brown which mentions the circle division problem I started off with — Moser’s circle problem, it’s called. This morning they posted another video which apparently goes into detail about the problem. I haven’t watched it yet, but I’m sure it’s worth watching.)

Not small numbers but differences

Sat, 01 Jul 2023 13:56:56 +0000

I guess it’s just finite differences, right? If you have numbers generated by a polynomial of degree $l n$ then the $l n^{th}$ order differences are constant. For instance, take $l g(n)=n^3+6n^2-4n-3$. Plugging in 0, 1, 2… you get

-3, 0, 21, 66, 141, 252, 405, 606…

Take differences between successive numbers and you get

3, 21, 45, 75, 111, 153, 201…

And repeat

18, 24, 30, 36, 42, 48…

Book review: How to Buy a Planet by D.A. Holdsworth

Sat, 01 Jul 2023 03:42:01 +0000

2.0 out of 5 stars

Douglas Adams this isn’t.

If you’re looking for funny jokes, they aren’t here. If you’re looking for skilled use of language, it isn’t here. If you’re looking for a plot line that makes any sense, not here. Plausible solutions to the problems the characters face? (Or deliberately implausible solutions for humorous effect?) Nope.

If you’re looking for annoying writing traits like repeatedly setting up something, rubbing your face in it, and then pointedly not explaining it until several chapters later — or not at all — that’s here. If you’re looking for at best two dimensional characters including a walking cliche of an absent minded professor, that’s here. If you’re looking for the kind of sexism that gives you three central characters of whom the two men undertake all the action and the woman does virtually nothing except look beautiful, that’s here too. (Yes, she saves the world at the end. Off camera. She’s shown going off to do it and then she’s shown having finished doing it.) Or the kind of sexism where all the bad guys are male (because a woman can’t possibly be a threat, right?). Or the kind of ethnic stereotyping of all the non-English humans in the story that would be right at home in a 1950s sitcom.

Circles and small numbers and meta-small numbers?

Sat, 01 Jul 2023 01:46:43 +0000

Here’s a rather well known mathematical gotcha. What’s the next number in this series: 1, 2, 4, 8, 16… ? Answer, of course, 31.

Draw a circle, mark some points on the circumference, connect every such point to every other, and count the number of regions the circle’s been divided into. With one point there are no lines and the circle consists of 1 region:

With two points there is one line and 2 regions:

3340 VCO notes

Sun, 25 Jun 2023 09:01:06 -0400

The Curtis CEM3340 VCO chip, introduced in the 1980s, has been used in many synths and synth modules. The Alfa AS3340 a is more or less drop in replacement; AS3340A is an improved version. Coolaudio has the V3340 version. The latter two come in DIP and surface mount packages.

The CEM3345 and AS3345 are less often used variants with two additional pins.

Regarding the AS3340A, the datasheet says:

AS3340A/AS3345A are improved versions of AS3340/AS3345. AS3340A/AS3345A and have [sic] much more output frequency stabilty against VCC and VEE…. AS3340A/AS3345A benefits from improved symmetry of rising and falling edge of triangle signal (approx.. 50%).

Skinny and damp

Sun, 25 Jun 2023 01:51:33 +0000

I was really asleep at the switch. Somehow the Syracuse Jazz Festival for this year eluded my attention until yesterday morning — a day and a half after it started. It was only then I found out Tuba Skinny would be playing in downtown Syracuse tonight!

Tuba Skinny and then Spyro Gyra and then Gladys Knight, in fact. And Friday night’s lineup was no slouch either: Postmodern Jukebox, Tower of Power, and Herbie Hancock.

Earthwalk Day 517 (23 June 2023), 5086 km: South Dakota

Fri, 23 Jun 2023 23:34:52 +0000

Here’s a mildly momentous occasion: I’ve entered South Dakota. Yes, I’ve done that before. But that’s the point. This is the first time this Earthwalk I’ve re-entered a state I’d been in before.

I’m about 160 km further west than I was when I left SD, though. Near the town of Lemmon. Per Google Maps’ directions I’m at an intersection the Street View car hasn’t been to, having come south from Lemmon on what’s evidently not much of a road. In fact, according to OpenStreetMap, the middle section of it isn’t there at all. But there’s something there in the satellite pictures, just perhaps not something your average car can use. So, okay, maybe I really did make it to that point. I could’ve taken Route 73, about 1.6 km further west, but evidently Google Maps didn’t think it was as suitable for a pedestrian.

Unbuilding the bath

Thu, 22 Jun 2023 00:17:49 +0000

After years of getting more and more annoyed with the bathroom floor, I’m doing something about it. Making it worse. OK, hopefully making it better by the time I’m done. Whoever tried to improve it last evidently used peel and stick vinyl tiles that lately have done less and less sticking and more and more peeling. My initial hope was that I could just pull up the tiles and put down something new but… no, I decided the underlayment had to be replaced and, even worse, the vanity cabinet. Which, granted, I’m sure was cheap when it was bought, and is in bad shape. Still, I’d hoped to postpone that, but no, it’s time for it to go. The toilet should be replaced too, but maybe not immediately.

Super simple — ?? — oscillator

Wed, 21 Jun 2023 14:20:43 -0400

What Look Mum No Computer (Sam Battle) calls the Super Simple Oscillator is described in this video (which followed up on this video) and this web page. That may be a case of too much information, because some of what is said and shown seems to be inconsistent with itself. I’m writing this article to try to make things a little clearer, and to bring you this warning:

If you’re looking to get into building electronics, maybe thinking about noise boxes and synthesizers, an oscillator consisting of only four parts might seem a great place to start. “I definitely can build that!” you might be thinking, and you’re right — you can. Whether you can get it working or not is another question, and if you can’t, it might not be your fault!

People have come to the LMNC Discourse forum looking for help getting the SSO working. Sometimes we’ve been able to help. Sometimes we’ve just had to say, “Look, this circuit is weird. We can’t see that you’ve done anything wrong and it may be you haven’t. Why don’t you build an APC instead? It’s more likely to work.”

Matching transistors

Wed, 21 Jun 2023 14:03:31 -0400

For certain kinds of circuits, notably (to us synth DIYers) exponential current converters and transistor ladder filters, you need matched transistor pairs. The gold standard is pairs of transistors fabricated on a common die and packaged as, say, an SSM2212; a notch below that are packages containing two similar transistors but not ones on the same die. But the cheapest option is to do it the old fashioned way: Get a bag of TO-92 transistors and find pairs that match.

How to vactrol

Wed, 21 Jun 2023 13:36:19 -0400

Look around the synth DIY world and before long you’re likely to find a circuit containing something like this:

Vactrol driven by CV through resistor

This is an attempt to give voltage control to a circuit, using a vactrol. A vactrol is a light source (classically a little neon or incandescant light, but these days an LED) and a photoresistor butted up against one another and enclosed in a light tight case — you can buy them, though they’re rather expensive, or you can make your own, though your results may be unpredictable. A voltage applied to R1 produces a current through the LED, which lights it up, which changes the resistance of the photoresistor, and that might change the cutoff frequency of a filter or the frequency of an oscillator or whatever. Easy voltage control.

PSU startup problem and how to fix it

Wed, 21 Jun 2023 12:48:06 -0400

There are lots of designs for synth power supplies around. Many of them are linear supplies in which there is a transformer — sometimes in the form of what’s affectionately known as a wall wart, sometimes built into the supply — that reduces the wall voltage to 12 VAC, which then is rectified with some diodes and filtered with some big capacitors. Then a couple of voltage regulators convert that to steady and accurate +12 V and -12 V outputs.

VCO tuning

Wed, 21 Jun 2023 09:40:28 -0400

Let’s look at how to set up a VCO to track at 1 volt per octave (1 V/oct).

This will apply to many VCO designs but I’m thinking particularly of 3340 based designs such as the LMNC 1222 Performance Oscillator or my Hero and Sidekick VCOs.

The idea is to get the pitch to change by 1 octave when you change the CV by 1 volt — or to change by 2 octaves for a 2 volt change, et cetera. A 1 octave change is a doubling of the frequency, so you want the frequency to go up a factor of 2 for a 1 volt change, 4 for a 2 volt change, and so on. So the first step is you need to be able to input voltage changes of exactly some number of volts.

AO Bus Board

Mon, 19 Jun 2023 01:23:21 -0400

The Analog Output Bus Board is a compact power distribution board for Kosmo and most Eurorack modules. Unlike typical Eurorack bus boards it uses 2x5 pin IDC headers, so handles only ±12 V and ground. (Kosmo does not use +5 V or gate and CV distribution — nor do most Eurorack modules.) Connections to the PSU are made through a 3-position screw terminal block, and LEDs indicate ±12 V power.

AO Power Supply

Mon, 19 Jun 2023 01:23:18 -0400

This is a power supply based on the MFOS wall wart supply. Differences are:

Added polyfuses
Added LEDs
Input is either barrel jack or pluggable terminal block, with another pluggable terminal block for daisy chaining
Output is a (non pluggable) terminal block
Regulators are vertical, with space for Tayda A-5093 heat sinks
1N4004 on positive regulator output changed to 1N5817
Board is shorter and wider (100 x 61 mm) to keep fabbing price low

Note that unlike usual Eurorack supplies, this one provides no +5 V rail. (Of course there are almost no Eurorack modules that use the +5 V rail these days, and no Kosmo modules do.)

Barton/AO IR Input

Sun, 18 Jun 2023 23:49:04 -0400

This is a modified version, in Kosmo format, of the Barton Musical Circuits 078 IR Input synth module. Barton describes the original version as follows:

This module is designed to allow infrared light sources to interact with your synthesizer. The most common household sources of infrared light are fire and remote controls. Infrared LEDs are also readily available to DIYers who wanted to experiment with creating new devices for controlling synthesizers through this module.

AO Wave Displacer [SB]

Sun, 18 Jun 2023 23:18:48 -0400

This is a wave shaping module. It adds harmonic content to simple waveforms, with voltage control. That’s all it was designed for, but it turns out it also can do other stuff ranging from the mundane to the utterly deranged — behaving as a comparator, a VCA, a mixer, a CV or audio switcher, a ring modulator, and more.

Barton Full Wave Dual Rectifier

Sun, 18 Jun 2023 23:18:48 -0400

This is the Barton Musical Circuits BMC021 Full Wave Dual Rectifier in Kosmo format.

I built it using the BMC circuit board mounted behind a Kosmo format fabricated FR4 front panel. I made some changes to the component values but otherwise did not modify the circuit.

Git repo (for the panel design)

Barton/AO VC 4046 Waveshaper

Sun, 18 Jun 2023 23:18:48 -0400

This is a modification of the Barton Musical Circuits 4046 Wave Shaper.

In Barton’s design the seven signals (which are 0, 1, 2, and 3 octaves above and below the input signal) go into a simple mixer with a potentiometer attenuator on each channel to produce the module output. This modification replaces that simple mixer with a voltage controlled mixer, allowing use of control voltages to modulate the mix. If any input has no CV plugged in, the corresponding pot behaves like a signal attenuator.

Kassutronics Wavefolder

Sun, 18 Jun 2023 23:18:48 -0400

This is a Kosmo version of the Kassutronics Wavefolder. It includes an extra jack and pot for a Symmetry (Odd/Even) CV and another extra jack for a second VCA CV, as described near the end of the Kassutronics build document.

The PCB is built according to the Kassutronics instructions except for the above additions and:

The jacks and pots are panel mounted
Since the -9 V regulator (LM7909) is hard to find, I substituted ±8 V regulators (LM7808 and LM7908)

Git repo (for the panel design)

AO Attenuators