using new technology on old machines. Was: PDP-12 Restoration at the RICM

Pontus Pihlgren pontus at Update.UU.SE
Mon Jun 15 15:46:35 CDT 2015

On Mon, Jun 15, 2015 at 04:55:57PM +0000, tony duell wrote:
> Unfortunately I believe you. Use at least a thousand times more components than
> you need to.

Actually it's just two, a Teensy and a usb cable. (Sorry, I couldn't 

> In general this worries me if you are restoring a vintage 
> minicomputer. How on earth can you hope to fix a TTL-built CPU without 
> knowing the common TTL chips and without having a few on-hand?

How do you suggest I learn? I believe you had a father that got you of 
to a good start and perhaps you even took a few classes.

My father was great but knew very little about electronics. And TTL on 
the minicomputer level was way out of fashion when I went to school.

Certainly no excuse, but one of the main reasons I'm in this hobby is to 
learn! And boy have I learned a lot since I got started. I'm not at your 
level yet.. but perhaps in a few years I'll be a tenth of the way there :)

It might please you to hear that the Teensy I'm talking about is in a 
socket on a perfboard together with a handfull of 74165 and 74374 which 
I've wirewrapped in proper wirewrapping sockets. It will become a USB 
interface for my 11/70 front panel. The Teensy was the simplest/cheapest 
way to get a usb interface with lots of I/O pins. (Why usb? to get a 
connection to simh on one of those newfangled Pi-things)


More information about the cctalk mailing list