curiousmarc
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Building an Apollo-style GSE control panel
🕑 Added 2021-01-06 23:15:51 +0000 UTCIt seems that a few of you had Apollo Twist-Lite switches in your drawers, and on top of that are generous enough to donate them to the channel. Thanks to your generosity, and also to some good eBay scraping for the few reasonably priced bits and pieces of Twist Lite switches, I have now accumulated a collection big enough that I could cobble together a small control panel.
That also meant I had to purchase many light bulbs. Viewer Ryan even sent me some LED replacements with the same lamp socket, that had been made for his company. With traditional bulbs, even with the lower power 40 mA indicator bulbs, at 4 lamps per switch, you are in the many amps even for a small panel!
The idea is to make a small Apollo GSE-like box (Ground Support Equipment), with a front panel inspired by one of the incomparable panels that were in the firing room. Which actually had more gauges and Roto-Tellites than they had Twist Lites (it's the Houston MOCR is that had gobs of Twist Lites).
Below are a few that have Twist Lites. We'll obviously not make something that grand, it's just for inspiration.
I purchased an industrial-looking enclosure at Excess Solutions, our sole remaining surplus store in the Valley, with the intent on transforming its front panel.
It contained a 5575B Micro BERT, which is a T1 tester. A T1 is an old phone trunk line, transporting 24 phone connections. It actually runs over a normal phone twisted pair (actually two, one in each direction), and carries 24 time-multiplexed, digitized PCM channels at 64 kb/s each, for a total of 1.5 Mb/s in the pair. It was one of the first big upgrade of the copper plant using digital modulation.
Does my T1 tester still power up?
You bet it does! The screen did not light up though, the CCFL is dead (I checked, there is 340V power to it, so the tube must be the culprit). Can I still test a T1 with it? Well, a T1 being just a mile-long twisted copper wire, it should work with pretty much anything. So I just plugged the cable I use between my 60 mA Baudot teletypes:
Sure enough, it's all green! But no one needs a T1 tester anymore, so out went the beautiful electronics. It's a Z80 processor inside with lots of Altera PLDs and nice analog electronics. The ICs date codes are from 1990.
Conveniently, there is a transformer at the bottom that I'll be able to re-use to power the switch lamps:
I machined a replacement panel out of an old HP blank panel (or at least that's what I think it was) that was too wide to be useful as a blank in a 19" rack. Color is right though:
The switches pop right in the slots, very convenient!
Wiring the switches is a relaxing break from debugging misbehaved vintage electronics. Here are my first two switches all lit up:
Too bad I don't have a laser engraver to do the legends, but I'll figure out something. It just needs a fake Apollo GSE sticker and we'll be all done, ready to use it whenever we need good looking buttons on a project.
Cheers everyone,
Marc
Comments
Chris M
Ah, T1 - I remember when we got a T3 in the office and had the fastest connection around.... And, yes, we lost a bunch of good recyclers in SV - Wierdstuff, Triangle, Halted and a bunch of others I've forgetten, including that crazy one near the Oakland airport....
adrian stoness
did u get a good photo or need a better one?
CuriousMarc
Hehe. Yes Adrian, I think it needs to have that one too! Thanks for the picture (that's from Adrian's very own genuine Apollo PSA tester that he had lent to us a while back).
