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c/electronics-repairersderekcarrderekcarr1d agoProlific Poster

Old guy at a pawn shop taught me how to read capacitor values in 2 minutes flat

Was at this run-down pawn shop in Tulsa about 3 years ago, looking at their broken electronics bin. This older dude, must have been 70, saw me squinting at a bloated capacitor and just laughed. He pulled out a little notebook from his shirt pocket, had this whole system written out for decoding values. Showed me the trick about that third digit being the multiplier, not the actual number. Then he pointed at another board and said "see how that one's bulging but the top is still clean? That's your tell right there." I still think about that lesson whenever I pop open a power supply. Anybody else have a random encounter like that where some stranger just dropped knowledge on you?
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grant130
grant1301d ago
That third digit trick changed my whole approach to fixing stuff.
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scott.grace
Honestly I'm gonna push back on this a little. That third digit trick is fine for basic stuff but it's not some magic bullet. I've seen people ruin perfectly good boards because they memorized that one trick and thought they were experts. Capacitors are way more complicated than just reading the numbers off the side - you gotta account for voltage ratings, temperature ranges, and whether it's electrolytic or ceramic. Plus those old guys at pawn shops aren't always right. I had one tell me I could fix a dead monitor by just tapping the capacitors with a screwdriver and I almost fried myself. Knowing one trick doesn't mean you know the whole picture.
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