Hacker News Reader

Hacker News

Comment by userbinator | Hacker News Reader

Full thread

userbinator

Note that in the early days of electronics, PCBs did not have soldermask, because it wasn't necessary:

https://en.wikipedia.org/wiki/File:IBM_SMS_card_circuit_side...

View on HN

Also lots of boards had transparent solder mask after that (Tektronix did this) which was great for debugging!

Examples here: http://golddredgervideo.com/kc0wox/tek/7504/detailedpictures...

Whole scope is a work of art!

Wow, gold everywhere. Even the ICs have gold-plated pins... that's not something I've seen before.

I’ve only seen one such circuit before and it was some kind of radiation hardened thing. It looked cool though!

They're beautiful. Good luck oxidizing any of that in normal environments, those scopes will outlast the people that built them. Old computer hardware used to be just like that, I would buy the boards by the pound in the 70's for parts. Gorgeous stuff.

Annoyingly the IC sockets tend to oxidise if the board doesn’t! I’ve lost count of the number of them I’ve had to replace in my life.

If it wasn’t for mechanical switches, pots, contacts and some dubious thermal design I imagine the kit would last for 100 years easy. I have 40-50 year old stuff on my bench in daily use.

There are sockets with gold plated turned inner pins, those do not oxidize. Cost a pretty penny though.

Yeah the Tek scopes were made before they came up with them though which is annoying. I usually replace them with the Harwin gold plated turned pin ones as I got a massive box off them from eBay for virtually nothing :)

It's pretty common in older test equipment. The production cost was phenomenal, of course, but the equipment was expensive too.

That was a very high end scope for it's day. It probably had to go in for calibration to a standards lab every 180 days.

Advanced Circuits (4pcb) still offers a "BareBones" service that will give you a 2 layer board without soldermask or silkscreen in 1 day.

I haven't used that service since maybe 2007, OshPark Super Swift and Chinese vendors have made it obsolete.

And the PCBs were tan or natural.

> And the PCBs were tan or natural.

They were tan because they were made of phenolic paper (wood fiber) laminate. Modern PCBs are moade of glass fiber epoxy laminate material and they're usually clear/white without any solder mask dyes.

Reply on news.ycombinator.com