A $9 capacitor tester saved me a week of guessing

I had this old receiver on the bench for 6 days, audio cutting out randomly on the right channel. I swapped boards, reflowed joints, even replaced the input jacks, nothing worked. Then I borrowed a cheap component tester from a buddy and found a 47uF cap that read 4.8uF when it was warm. It tested fine when cold, that's why my meter missed it every time. I picked up my own unit for 9 bucks and now I check every electrolytic with heat from a hair dryer. Has anyone else run into caps that only fail when they're warm?

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saraho482mo ago

...and that's why I now keep a hair dryer next to my soldering station, right next to the deodorant spray I use to freeze stuff. Those caps are drama queens, they only act up when they've got an audience and a little heat. I swear my old receiver had a personal grudge against me, it would work fine for hours then cut out right when I was about to call it fixed. Now I just microwave my old caps, metaphorically speaking, and call it a day. If it ain't holding 47uF after a good heat blast, it's going in the parts bin of shame.

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