TIL those cheap capacitor testers on Amazon are wildly inaccurate

I was fixing an old receiver from the 80s and used my $15 component tester on some caps. It said they were all good but the thing still wouldn't power up. Decided to actually desolder them and check with a $40 multimeter from Fluke and 3 out of 4 showed way low capacitance values. Found a video from a guy in Texas who tested 10 of those cheap testers against a proper bench meter and every single one was off by at least 20%. Anyone else waste hours chasing ghosts because of bad gear?

2 comments

2 Comments

craig.sage23d ago

lol yeah I remember reading something about that actually. There was a guy on a forum who said he tested a bunch of those cheap testers and found out they basically just guess the value half the time based on the size of the cap. Apparently they cant handle ESR well either which is huge for old gear like that. Its wild how much time we waste trusting gear that costs less than a pizza.

the_rose23d ago

I was totally team cheap tester until I read that same thread. Changed my mind completely.