Over on his YouTube channel our hacker [Jerry Walker] repairs a Tektronix 577 curve tracer.
A curve tracer is a piece of equipment which plots I-V (current vs voltage) curves, among other things. This old bit of Tektronix kit is rocking a CRT, which dates it. According to TekWiki the Tektronix 577 was introduced in 1972.
In this repair video [Jerry] goes to use his Tektronix 577 only to discover that it is nonfunctional. He begins his investigation by popping off the back cover and checking out the voltages across the voltage rails. His investigations suggest a short circuit. He pushes on that which means he has to remove the side panel to follow a lead into the guts of the machine.
Then, in order to find the shorted component he suspect exists, [Jerry] breaks out the old thermal cam. And the thermal cam leads to the fault: a shorted tantalum capacitor, just as he suspected to begin with! After replacing the shorted tantalum capacitor this old workhorse is like new.
There are probably quite a number of repair lessons in this video, but we think that an important takeaway is just how useful a thermal camera can be when it comes time for fault finding. If you’re interested in electronics repair a thermal cam is a good trick to have up your sleeve, it excels at finding short circuits.
If you’re interested in repairing old Tektronix gear be sure to check out Repairing An Old Tektronix TDS8000 Scope.
I’m sure there are people out there who would insist on using period tools to repair something like this, but I’m definitely not one of them. Every bench should have a thermal camera at this point, or at least a thermal dongle. Good show!
With this old Tek gear, if a power rail goes down, it’s always a tantalum capacitor.
I have a 577 too, and it has a shorted tant that was nice enough to give a visual indication of its fault.
I’ll replace it and service the whole instrument one day…
recently bought a 6.5GHz spectrum analyzer off eBay and poof! went the tantalum hah. after replacing it, it was almost fully functional
except for the HP attenuator inside with tiny plastic actuators that have two o-rings for, I suppose, prevent slamming. you can imagine the condition of 30 year old rubber
lucky a $10 kit of watch crown o-rings was the solution
I had one give off magic red smoke, bingo. They tend to short rather than go open.
I recently repaired a Fairchild 6200B curve tracer, from 1967. It wasn’t as nice as the Tek 577, and there were things about it that were amusing to us who didn’t even start into the industry until a decade and a half later; but all it needed was its switches sprayed with contact cleaner.