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

[Mark J. Blair]

> On Jun 15, 2015, at 09:53 , tony duell <ard at p850ug1.demon.co.uk> wrote:
> 
> 
>> I also think it is in the spirit of the computer - using what is available
>> to fix a problem at hand. I think the arduino was overkill when an attiny
>> (smaller, easier to hide) would probably serve just as well.
> 
> Would you put plastic handles on a piecc of antique furniture? Would you 
> make the seatboard for an antique longcase clock from MDF? 
> Both are easily reversable, BTW.

Sure! Temporarily and reversibly, of course, and I'd hope to replace them with proper stuff when possible. But to bring up an old computer system right now, I'll kludge in what I have available to get it running. In that respect, an Arduino-based baud rate generator could be considered test equipment rather than a component.

>> If you have the ttl logic bits lying around and know how to use them, fine.
>> Still would probably need debugging.
> 
> FWIW I have made programmable dividers on a couple of occasions recently
> (one was a 100/120 flash-per-second stroboscope, the other was the transmitter
> half of a modem to talk to TDDs). Both of them worked first time. I guess it's just
> what I am used to.

Exactly. And for somebody who doesn't already have a full stock of TTL parts on hand, a different solution may present itself. I play with gear from WWII military radios up through thoroughly modern electronics. When I work on a WWII radio, it might be considered cheating to poke at it with my Fluke multimeter, Tek DSO, HP spectrum analyzer or HP synthesized signal generator (the latter two of which are slaved to my GPS-disciplined frequency standard), but those are the tools I have on hand, so those are the tools that I use.

-- 
Mark J. Blair, NF6X <nf6x at nf6x.net>
http://www.nf6x.net/