Archive for category Oddities

Monthly Image: AMP Plug Board

Around 1960, somebody my father knew at the Harrisburg AMP factory gave me a chunk of plugboard bandsawed from a scrapped computer or industrial controller, because he knew I’d enjoy it:

AMP Plug Board

AMP Plug Board

He was right.

I spent months rearranging those little cubes (some with cryptic legends!) into meaningful (to me) patterns, plugging cables between vital spots, and imagining how the whole thing worked:

AMP Plug Board - detail

AMP Plug Board – detail

Long springs ran through the notches under the top of the blocks to connect the plug shells to circuit ground. The ends of the steel rails (still!) have raw bandsaw cuts, some of the blocks were sliced in two, the tip contact array behind the panel wasn’t included, and none of that mattered in the least.

Only a fraction of the original treasure trove survives. It was absolutely my favorite “toy” ever.

Quite some years ago, our Larval Engineer assembled the pattern you see; the hardware still had some attraction.

I’ve asked Mary to toss it in the hole with whatever’s left of me, when that day arrives …



Power Over Audio

An obsolete Intuit / Roam Data credit card reader emerged from the heap:

Intuit Roam Data Reader

Intuit Roam Data Reader

“Turn up the volume” suggestes where the power comes from:

Intuit Roam Data Reader - plug wiring

Intuit Roam Data Reader – plug wiring

They drive a LOUD, probably square-ish, audio signal through both “earphone”channels, rectify and regulate the output, and have plenty of power for the reader. The card data returns through the “mic” as another audio signal; I assume they choose an encoding well-suited for a dab of DSP decoding.

Nowadays, of course, 3.5 mm jacks are obsolete, audio data travels by Bluetooth, and you must keep a myriad of batteries charged at all times.


Everybody Wants to be a Star

The Wzye Pan camera overlooking the bird feeders attracted the attention of a Downy Woodpecker:


Screenshot_20181029-112307 - Downy Woodpecker at the Pan

Screenshot_20181029-112307 – Downy Woodpecker at the Pan

The camera sits on a “guest” branch of the house network, fenced off from the rest of the devices, because Pi-Hole showed it relentlessly nattering with its Chinese servers:

Blocked Domains - Wyze iotcplatform

Blocked Domains – Wyze iotcplatform

In round numbers, the Pan camera tried to reach those (blocked) iotcplatform domains every 30 seconds around the clock, using a (permitted) lookup to check Internet connectivity. Pi-Hole supplied the latter from its cache and squelched the former, but enough is enough.

I haven’t tested for traffic to hardcoded dotted-quad IP addresses not requiring DNS lookups through the Pi-Hole. Scuttlebutt suggests the camera firmware includes binary blobs from the baseline Xaiomi/Dafang cameras, so there’s no telling what’s going on in there.

The Xiaomi-Dafang Hacks firmware doesn’t phone home to anybody, but requires router port forwarding and a compatible RTSP client on the remote end. Isolating it from the rest of the LAN must suffice until I can work out that mess; I assume the camera has already made my WiFi passwords public knowledge.

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Sharing the Road on Raymond Avenue: Squeeze Play

We’re riding home with groceries along Raymond Avenue, approaching the Vassar Main Gate roundabout, and, as is my custom, I’ve been pointing to the middle of the lane for maybe five seconds as I move leftward to take the lane:

Raymond Passing - Approach - 2018-10-04

Raymond Passing – Approach – 2018-10-04

The driver of HCX-1297 is having none of it:

Raymond Passing - Near Miss - 2018-10-04

Raymond Passing – Near Miss – 2018-10-04

The mirror passed maybe a foot away from my shoulder; I’d reeled my arm in as the front fender passed by.

All three traffic circles / roundabouts on Raymond neck the lane down and angle it rightward into the circle, which is supposed to “calm” traffic:

Raymond Passing - Roundabout - 2018-10-04

Raymond Passing – Roundabout – 2018-10-04

The design doesn’t allow much flinch room for cyclists and certainly isn’t calming for us.

The NYS engineer who designed the Raymond roundabouts said the whole thing was “standards compliant”, refused to go on a check ride with me to experience what it was like, and told me to detour through the Vassar campus if I felt endangered while sharing the road.

Obviously, NYS DOT personnel do not dogfood their “share the road” bicycle standards by riding bicycles.




This just in (clicky for more dots, but not clearer dots):

Spam image - xxx

Spam image – xxx

Yes, the attachment was named xxx.jpg, presumably so I wouldn’t suspect it of containing anything untoward.

The name-dropping definitely adds verisimilitude: not just Microsoft (or Micro Soft) Windows and Google, but Yahoo, too. Be still, my heart!

It’s unclear how I would contact their “fiduciary agent in LIMA PERU” by dialing a 909 area code in California or sending an email to, um,, but, hey, why not? Perhaps another version of me in a parallel universe used the Peruvian Internet?

This must be one of those scams where, if you’re bright enough to notice the problems, they won’t need to waste any time on you.

You’re welcome to my identification numbers. When you get the check, slip me maybe 100 large, preferably under the table, and we’ll call it square.



Powered Prototype Board: Laying-on of Hands Repair

One of my very first projects, after setting up my very first home shop in our very first home, was building an overly elaborate prototype board with five (!) linear power supplies:

Proto Board - overview

Proto Board – overview

The components come from the mid-70s and the shop happened around 1980, so it’s been ticking along for nigh onto four decades. Of late, the supply voltages became erratic and I eventually popped the top:

Proto Board - innards

Proto Board – innards

Yeah, linear pass transistor regulators driven from bulk cap storage, hand-hewn bridge rectifiers, and multi-tap transformers. Everything mounts on screws tapped into the 1/8 inch aluminum chassis, with power transistors on a huge finned heatsink attached to the rear panel. The thing weighs 11.6 pounds = 5.3 kg.

Not a trace of firmware to be found. Heck, surface-mount components hadn’t yet come into common use.

The circuitry lives on a crudely etched phenolic board:

Proto Board - etched circuit board

Proto Board – etched circuit board

There may be a schematic somewhere in my collection, but it hasn’t surfaced in a long time. I’m mildly surprised I didn’t tuck it inside the case, which may have been a life lesson yet to be learned.

Based on my recent experience with the Tek AM503, I wiggled the two metal-can regulators and the ceramic (!) regulator, gingerly plugged in the line cord, flipped the switch, and all the supply voltages once again work perfectly.




Driving While Inattentive

When you come upon a scene like this, you know someone’s having a Bad Day:

Rt 376 Collision Scene - approach - 2018-09-21

Rt 376 Collision Scene – approach – 2018-09-21

I rode slowly past a line of stopped cars, became a pedestrian, walked through the lawns on the left, then turned back into a bicyclist.

It appeared to be a three-car collision, with two vehicles aligned almost perfectly nose-to-nose in the northbound lane:

Rt 376 Collision Scene - overview - 2018-09-21

Rt 376 Collision Scene – overview – 2018-09-21

The red 2015-ish Forester apparently snagged a rear wheel on the far side of another contestant:

Rt 376 Collision Scene - Forester - 2018-09-21

Rt 376 Collision Scene – Forester – 2018-09-21

Talk about heart-stopping: Mary had driven off to a meeting some hours before. Even though the wrecked Forester differed in enough details to make me absolutely certain it wasn’t ours , Mary got a firmer-than-usual hug when she got home.

A picture not shown: two expressionless officers supervising a guy having great difficulty walking the fog line.

I’ll never know the rest of the story, but the overall outline seems clear.

Other than that, it was a fine day for a ride