+1 for can-opening it to save wear and tear on the board. If you
> measure 45 ohms ESR in-circuit, it won't be better by itself.
Well, it's hardly surprising for an electro of this age. Clearly the original component from a scope with a s/n indicating it was manufactured
Sounds about par for the course. Go back further to paper caps and it'd be a surprise to find any still working properly. And yes, micamold were paper caps.
NT
You're not kidding. My largest iron is 40W/80W switchable. 40W won't touch it and I'm not risking 80W! The biggest problem seems to be the cap case - a long 1" dia aluminium tube with 3 tags at the bottom going straight to PCB grounds. It's acting like a very effective heat sink. Going to have to trash the caps from above.:(
I have a Keithley 410 Micro-Microammeter from about 1960 that has all its original electros and still works fine. Of course it uses an electrometer tube, so it takes a good couple of hours' warm-up to settle down on the 100-fA FS range, but it eventually does.
It has way more soul than my 610C(*), but really isn't nearly as good a meter. (Don't anybody tell it, though--it has an honoured place on my bench shelf.)
Cheers
Phil Hobbs
(*) "Now Nortons and Indians and Greeveses won't do...They don't have a soul like a Vincent '52." -- Richard Thompson
Cursitor Doom prodded the keyboard with:
Have you tried making a soldering bit with a piece of split copper tube and a cooks torch to heat it. Apply to all the pins up at once.
I've got a box full of the oil & paper caps that come in cubiod cans and they all tested fine (I have an awful lot of vintage spares here). Not so sure about the tubular paper caps which I assume you're talking about, though.
Moisture + acid paper + foil = mess. That'll take a lot longer if the cap has metal on five sides.
Cheers
Phil Hobbs
My prewar metal can paper caps are all wax sealed, and every last one tested dead as a very dead thing. The non-metal seal is where it can go wrong. Not sure why they didn't use bitumen.
NT
Enjoy your PCBs.
and not the good type
NT
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