Still prototyping analog computing modules. Moving stuff from breadboard to prototyping boards ("ElectroCookies"). (Red & blue "cookie" seen here.) An article from a 1970's hobbyist electronics magazine inspired the project. I've gone past that circuit now though. (Unsure where I'll land…)

Playing with analog computing (but digital metering, so sue me). Last night (after several hours of hair pulling) I learned that a 1% 10 kΩ resistor color bands is indistinguishable from a 1% 120Ω resistor—that is flipped around. Breadboarding is messy. Will make up a PCB for part of it soon.

Scored my copy today. Limited run, FWIW.

I put together an electronics kit + book intended as a gentle introduction to transistors and early computer logic gates (resistor-transistor logic or RTL). I set up a Tindie store page for the little over a dozen I have readied. (I'll create a web site soon.) www.tindie.com/products/jca...

A second analog (integrator) channel breadboarded (top). Both channels are tapped and displayed on the ESP32 "software meter" in the center (showing two needles at once). The new channel uses dual op-amps instead of singles. I may make another analog channel and have a go with a quad op-amp.

From breadboard (left—wires can be bumped loose) to protoboard (right—wires soldered). One channel of an analog/digital hybrid computer experiment. An op-amp acts as an analog-computer integrator, 3 more op-amps scale, offset & invert the voltage so it is within 0.0-3.3V range for the ESP32 ADCs.

Each year the wife hand-carves a multi-color X-mas card. A destructive process: inking/printing a color before carving for the next color. This year I suggested she make just one print at each stage (in black ink) for me to scan digitally—print on the Risograph. Seems to be going well.

Dialing back to the 1990's and the first commercial Glider (4.0) game… Ward Hartenstein blew my mind when I downloaded his "Hands-Off House" from AOL. You don't touch the controls to play—the house itself takes care of moving the glider along. B&W version playthrough: youtu.be/nIzy_Fmjexs

Just having some fun at Pioneer's expense, I guess. #SpacetoberChallenge #sciart #spaceart #illustration

Sweep meter is better. (Here it is responding to potentiometer acting as a voltage divider.)

Working on an "analog" voltage meter for a project. (This slide-rule version will not make the cut.)

After all this iteration, I placed an order for (I hope) the final board. Finishing up the instruction manual as well. I should have the boards for sale on Tindie in November. They're a kind of "breadboard helper" for playing with (learning about) transistor logic circuits.

I've just posted a video that *tries* to document the overwhelming nature of the event (overwhelming in a good way, of course). And I think I only covered like 1/3 of the show floor! Video: www.youtube.com/watch?v=hF0N... Blog post: www.jeffgeerling.com/blog/2025/vc...

youtu.be/vyeeQAcho00 Looks like Gruez (sp?) has posted a nice Glider history.

Prototyping my first learning-electronics project kit is winding down (I am finishing up the manual as well). Top is through-hole, bottom my first go at surface-mount (I learned a few things and have changed it some). (Hard to find a domain name these days. Went with CircuitPixies.)

Another Riso experiment with Crimson, Sky Blue and Black inks. #riso #risograph

My oldest daughter and I each have refurb'ed Riso machines. But she has a blue ink drum and I do not. With her visiting for a few days, she brought her drums and I was able to test a few Riso ideas out. #riso #risograph

Thanks, @ronscompvids.bsky.social for your midwest hospitality at #vcfmw this year. (And so many Mac laptops!) See you next year.

The process of prototyping an electronic project/PCB (from top to bottom). (I'm finishing up the project book now.)

Some somber thoughts on genealogy and the introduction of the camera. engineersneedart.com/blog/camera/...

Writing about your most embarrassing fuckups was, I thought, supposed to be more cathartic. Like the line from "Pink Rabbits", it wasn't that at all. 🫤 engineersneedart.com/blog/almostf...

So a guy (Daniel Valcanover) has spent 25 years trying to find a boxed version of the original Glider for Windows has tracked one down. Apparently he'll post the binary on MobyGames soon. Maybe here: www.mobygames.com/game/3998/gl... Even a photo of the box was unobtainium — until now of course.

I'm not sure I ever received the floppy disk, but I have the box and manual for the (rare?) Japanese version of Glider 4.0. Maybe someone can track down the binary. #VintageMac #RetroGaming

Placemat you might have found in a diner in 1960. I picked up a 1960 book of these placemats and I'm scanning all 200+ of them to upload to archive.org. It's one of those things I do from time to time. I'll post when available. Interstate 80 has mostly replaced US Highway 6 (below):

Finally (took 3 days of failed attempts) got Rocky Linux 9 installed with NVIDIA driver + CUDA toolkit so I can run Ollama on my an inexpensive 24GB NVIDIA TESLA M40 (seen on right — had to 3D print a shroud + add fans to the card). Just tried phi4. Tokens are smokin'. #localllama

One last video for #Marchintosh ! I take a look at @engineersneedart.com unfinished Mac games. www.youtube.com/watch?v=MlHs...

www.colino.net/wordpress/en... Discussion on HN: news.ycombinator.com/item?id=4349... #VintageMac #RetroGaming #RetroComputing #VintageComputing

Custom water-slide decals arrived. They help take this balsa model to the next level. Studio-scale model (about 44" long) was designed in Affinity Designer, laser cut, coverered with Monokote. Then painted & a few 3D modeled parts added. Now decals. From "2001: A Space Odyssey." #scifimodelling

Things I miss about California: #1) The Pacific Pinball Museum in Alameda, CA #pinball

My #minirack & #homelab is just getting started. Two Pis share space with a switch. A Pi 4 is running OpenWebRX+ & has two SDR boxes attached. I can scan the radio spectrum from any browser. Other Pi (5 with 16GB) is running Open WebUI & a number of local LLMs. Hoping to add a #GlobalTalk device.

In knew in 2021 that it was my last year working at Apple. So I suddenly started looking at where I worked as though I was a tourist. Here are some Apple Park photos. Perhaps you'll understand why I have described it as something like a beautiful art gallery — with no art. #MARCHintosh

Duane Blehm was the indie gamer that wrote early Macintosh shareware games: Stunt Copter, Cairo Shootout… Here's a little about him and his influence on me. engineersneedart.com/blog/duane/d... #VintageMac #RetroGaming #MARCHintosh

Of course we stopped for the photo-op. #VintageMac #RetroGaming #itwasamacgamecalledgliderfromthe90s

Brett, rest in peace. You were loved.

Photo from 2002 — PowerBook G4 Titanium. As an engineer at Apple, this is what we would get internally in order to make sure our code worked (I worked on the Displays Prefs). (Keyboard & trackpad appear removed.) Tossed when the device shipped. (A few became digital picture frames.) 😉 #MARCHintosh

Visual Pinball X (a.k.a #vpx) is a free & open #virtualpinball game that supports cabinets with surround sound, haptic feedback etc. A full-size cab is a real investment, but you can get close with a smaller, DIY controller like this one (part 1): engineersneedart.com/blog/quarter... #pinball

There's a long story about the Pioneer 10 & 11 plaque and the controversy: en.wikipedia.org/wiki/Pioneer.... (I'm flagging this for "Nudity" since we seem to live in less enlightened times than in 1972.) My contribution to MARCHintosh, ha ha. #MARCHintosh

When I was young, I discovered these amazing (if unfortunately named) "The Boy Mechanic" books from Popular Mechanics in the early 1900's. I spent a weekend with a farm family that had a set. Reminds me that rural were quick to adopt tech 100+ years ago. archive.org/search?query... #nonfiction

After 3 or 4 day's work, I finished up the "panelling" (left) on the studio-scale space clipper from the movie, "2001: A Space Odyssey". Now I am putting white over the top to take it down (right). I'll probably take it down even more than it appears in the photo. I prefer subtlety. #scifimodels

Welded the four subwoofer pieces together. (Ignore the wild color scheme — using whatever cheap filament is on hand.) Some PNIG (Plastic, Non-Inert Gas 😉) welding on the inside joints using a cheap soldering iron & filament (see joint through hole). Works pretty well. #3dprinting #bambulabs #hifi

I'm trying to recreate a subwoofer that I designed & built years back. Using FreeCAD this time & 3D printing. In the early, experimental stage. Using a spool of regret-filament to make a half-scale model, & a full-size but quartered model. Print-bed size limitations… #hifi #3dprinting #bambulabs

Created vector-based decals for the studio-scale "2001" space clipper I am building. I sent them off to have a sheet of water-slide decals made ($50, ouch). Affinity Designer is my drawing program of choice. No Adobe -rental crap, just download/buy the app and go. #scifimodels #affinity #adobesux

Huge fan of The Muffs — hard to believe Kim Shattuck died over 5 years ago. The most incredible thing to come since her death were two tribute video compilations by Japanese bands. If you're a fan, these are sometimes hilarious, always amazing. #1: youtu.be/5GiL7FJIHRQ #MusicSky #MusicChallenge

A few people have asked how the Cone Clock I made works (see post history). It's quite simple. The mechanism is attached via its "hour barrel". It is imbalanced — the battery weighing down one end, so that part of the mechanism is hanging down while the clock/cone rotate about it. #3dprinting

No big deal, but I was pleased I was able to host an LLM locally on a 16 GB Raspberry Pi 5 with a Web UI frontend so that I can connect to it from any machine/browser in my home. Yeah, slow as balls. It will interesting to try to find a model more appropriate for the slow Pi. #llm #localllm

Two full-range speakers 3D printed. Hooked them up to a Darling tube amp I built some time ago (about 2 Watts). The table they're on is actually a "speaker table" I built (with its own full-range drivers — not hooked up here). It has a down-firing sub though. A.B.I. #HiFi #3Dprinting #bambulabs

The kids are printing speaker enclosures these days. So thought I would riff on these truncated rectangular prism speakers I found in an old magazine. The biggest thing I've printed on my Bambu (ate ½ Kg of filament). Sealed cab, driver is full-range. #hifi #fullrange #3dprinting #bambulabs

Serial is working. Fed a paper-tape program to the PAL-II (KIM-1 clone). Here it is doing "the wave". On my Mac I had to use the app "Serial" (apps.apple.com/us/app/seria...) and an FTDI-based USB-to-serial adapter. #VintageComputing #kim-1

My PAL-II (KIM-1 clone) kit is assembled and running. Now to hook up serial and make programming it a lot easier. I ordered the kit from the same guy that created the excellent PAL-1 (a good deal if you get one before they're gone). www.tindie.com/products/kim... #kim1 #VintageComputing #kim-1

The 3 Williams arcade cabs are on the wall — fully operational. Robotron, Joust & Defender. I still need to give them colorful marquees — perhaps some art on the sides/bezel. Custom scripts mean the games launch right into the correct ROM, shutdown when you quit. #retrogaming #arcade #raspberrypi