Hi,
I'll add what's arguably a 'nice to have' to the list.
I was going to design/build a capacitor leakage tester with several selectable voltages, basically a high-voltage meg-ohm meter, until I discovered a device already existed which does exactly that.
I'd always assumed that insulation testers (usually 'Megger' though there are others) used a
fixed voltage, often too high (500V) for capacitor leakage testing.
Then I encountered the
Megger BM8/2 - a
multi-voltage insulation tester. It's analogue, battery-operated, the internal circuitry is fairly simple (so should be repairable); measures resistance at selectable voltages with ranges as follows:
- 0 to 1,000MΩ at 50V
- 0 to 2,000MΩ at 100V
- 0 to 5,000MΩ at 250V
- 0 to 10,000MΩ at 500V
- 0 to 20,000MΩ at 1000V
(All ranges include infinity of course; the above are the limits of what can be measured on the meter's scale.)
This looks
much more useful than a fixed-voltage tester; one of those
"why didn't anyone tell me these things existed sooner?" bits of test gear!
They're not particularly expensive as they've been superceded by a digital version, seem to be fairly common and turn up second-hand often enough.
I've just bought one (though I wouldn't class it as 'essential'; in-circuit measurements, substitution and 'on-sight' replacement of certain types have served adequately well so far.) But, given the amount of faulty vintage electronic hardware I've accumulated, anything which helps identify faulty components more readily means I might get more of it working!
Regards, Kat