So yeah, here I was thinking I had it all covered and was starting to build my ASCII encoder. I had bought a slew of resistors of different values from Ebay on the cheap. I think I paid $20 for 30+ different values. But of course, I wasn’t thinking ‘vintage’. And on installing the first one on my ASCII encoder, I realized right away I didn’t like the look of it.
The whole point of this TV Typewriter project is to produce something that is as close to 1973 specs as possible. Now of course, it’s probably not going to be possible to get everything vintage. At least not right away, but it is something to try for and I had simply gotten lazy with the resistors, figuring they were such a minor part nobody would notice.
Unfortunately once I installed that first one, I noticed. The electric blue colour just looked wrong in context. I mean, it wouldn’t have been entirely inconsistent to use some new ones. After all, after 40 years, stuff breaks. I could simply say ‘well by now, some of these would have had to have been changed out’. But I had gone to all that trouble getting correct vintage ICs. If there was the possibility of getting period correct resistors (and diodes), I wanted to do it.
Turns out ebay has huge stocks of vintage electronic components. And soon I had hit the jackpot with an auction that offered vintage Allen Bradley carbon composite resistors of virtually every value. I was able to do a one stop shop and get them all!
They just look so much more correct.
Now, I was given some warning about these. Resistor technology has advanced a lot in the 4 decades since this project came out. Old carbon composite resistors had a tendency to ‘wander’ over time and were not as precise as today’s carbon film. I guess as I embark on building the encoder in earnest, I’ll have to check each of these with my multimeter, and hope any wandering happens years from now, and not while this novice hobbyist is trying to get the thing working! But yeah, cross fingers, on to building we go!