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I'm pretty sure Don's still alive and since he welcomes contact, you can call him :-) He's a nice fellow to talk to. A surprising number of those devices are s

I'm pretty sure Don's still alive and since he welcomes contact, you can call him :-) He's a nice fellow to talk to. A surprising number of those devices are still around, but some may command premium prices since their only use is for legacy replacements. No one in 2023 should be using a 741 op-amp, but you can still buy them. I actually used a 74LS245 in a new project last summer as a 3.3 - 5V level converter because actual level converter chips were Unobtainium! DIP packages are still around, but tend to cost more than SMT probably because of economies of scale and physical size. You can wire wrap!!! Now there's a technology from the past :-) I recently bought wire wrap wire (makes good protoboard connections) but it's been a long time since I saw a wire-wrap socket outside one of my parts drawers. Surplus suppliers like MPJA, BG Micro and Jameco probably still have lots of them. Don't know where you're going to find a wire wrap tool tho.

WalterBright 4y ago
In my experience wirewrapping boards, never use the hand wrappers. They don't wrap tight enough, and after a year or so you'll be bedeviled by random glitches. Don't get a battery one. Get a plug in one. They wrap nice and tight enough to cold weld the wire to the pin. Besides, they're a joy to use. BZZT! and they're done.
- kjs3 4y ago
  As I have said elsewhere on HN, I can count on a small number of hands how many times I delt with someone who knew how to wirewrap and had decent tools wrapping a bad joint. That stuff went to space, and war, after all. Oh, sure...after 30-40 years those DEC Unibus backplane wraps sometimes got a little flaky depending on mechanical stress (as my VAX attests), but I think we can forgive that. It was the novices with a pencil wrapper and a couple of dozen wraps under their belt that gave it a bad rep.
smcameron 4y ago
Heh, a 741 op-amp was my very first guitar amp. I used that while I saved up to get a real amp. I had some janky circuit I made up using a 9v battery, a few resistors and a little speaker and some scant knowledge from my EE 214 class. Got some sick distortion out of that thing. But I think my circuit drew too much current because the op-amps would only last a week or two before burning out (and ran quite hot), but they were cheap to replace. Details are a bit sketchy because this would have been in 1991.

WalterBright 4y ago

In my experience wirewrapping boards, never use the hand wrappers. They don't wrap tight enough, and after a year or so you'll be bedeviled by random glitches. Don't get a battery one. Get a plug in one. They wrap nice and tight enough to cold weld the wire to the pin. Besides, they're a joy to use. BZZT! and they're done.

kjs3 4y ago
As I have said elsewhere on HN, I can count on a small number of hands how many times I delt with someone who knew how to wirewrap and had decent tools wrapping a bad joint. That stuff went to space, and war, after all. Oh, sure...after 30-40 years those DEC Unibus backplane wraps sometimes got a little flaky depending on mechanical stress (as my VAX attests), but I think we can forgive that. It was the novices with a pencil wrapper and a couple of dozen wraps under their belt that gave it a bad rep.

smcameron 4y ago

Heh, a 741 op-amp was my very first guitar amp. I used that while I saved up to get a real amp. I had some janky circuit I made up using a 9v battery, a few resistors and a little speaker and some scant knowledge from my EE 214 class. Got some sick distortion out of that thing. But I think my circuit drew too much current because the op-amps would only last a week or two before burning out (and ran quite hot), but they were cheap to replace. Details are a bit sketchy because this would have been in 1991.