Reverse-engineering an IBM Mainframe Vacuum Tube Pluggable Module

In this episode, we get our hands on a pluggable module out of an IBM vacuum tube computer. IBM used these awesome modules that could be pulled out as a unit, and each module consisted of some type of circuit. For example, some were cathode follower buffers, some were dual inverters, and so on. I’m not really sure what this one is, so today, we’re going to see if we can’t figure out how it works!

Thanks for watching!

Wiring diagram: https://i.postimg.cc/R02jHFm3/Wiring.jpg
Schematic: https://i.postimg.cc/cHYPMS1F/Schemat...

IBM 604 Engineering Manual: http://www.bitsavers.org/pdf/ibm/604/...
IBM 650 Engineering Manual: http://www.bitsavers.org/pdf/ibm/650/...
Computer picture 1: https://commons.wikimedia.org/wiki/Fi...
Computer picture 2: https://commons.wikimedia.org/wiki/Fi...
Pluggable module picture 1: https://commons.wikimedia.org/wiki/Fi...
Pluggable module picture 2: https://commons.wikimedia.org/wiki/Fi...
Music: Suco de Melancia by Red Tailed Fox - https://ocremix.org/remix/OCR01671