Schematics of Atanasoff-Berry Computer logic circuits?

[William Blair]

>  I'm not very familiar with vacuum tube circuit design, but I
>  have a PDF copy of the 1952 USAF technical order TO16-1-255
>  "Basic Theory and Application of Electron Tubes" which looks
>  like it might be sufficient. 
> 
> Is that on line, or could you post it?  

I found it on an excellent vacuum tube resource page intended for audio amp builders, but I can't find that specific page right now nor will a google search for that title and with filetype:pdf result in proper hits, so I've uploaded the 16.6MB pdf here:

http://tinyurl.com/5dh946

You can review the entire document on-line.  Just click on the tiny "download" icon above the preview to download it.  You've got to register to download from this site, but it's free, doesn't result in any spam and is well worth it.  I've found lots of interesting tech stuff there over time.

> Logic circuits are DC coupled, though, unlike audio
> amplifiers.  So the shift in operating point from the plate
> voltage change (or, for that matter, from a change in vacuum tube
> type, if you're doing that) probably means you'd have to change all
> the coupling resistors. 

Man, do I know that now.  I posted my comment before I'd fully digested the ABC web page.  A multi-stage direct coupled vacuum tube circuit.  Fun.