TTL homebrew CPUs

Chuck Guzis cclist at
Wed Jul 11 18:41:49 CDT 2007

On 11 Jul 2007 at 18:12, Ethan Dicks wrote:

> There are plenty of 1970s designs for those - I have them in the Sams
> "555 Timer Cookbook", and, I think, in "Don Lancaster's TTL Cookbook"
> (he dips into 555 designs as they interface to TTL circuits).  I don't
> think there are any listed designs that go up that high there, but
> extending what's there isn't too difficult.  One doesn't need a 90VDC
> 1A power supply for blinking nine neon bulbs.

As long as we're discussing antique technology, why not a vibrator 
and step-up transformer?  Then one can recitfy the AC by means of an 
aluminum-borax rectifier.  What the heck, a 9v transistor radio 
battery is too new, anyway.  How about some crowfoot cells?           
Perhaps one could simply do away with the neon lamps and substitute 
air spark gaps (using plate glass capacitors, of course) and power 
the whole affair with a coal-fired steam engine driving a winshurst 


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