Took me 3 hours to find a blown capacitor on a 1998 monitor

I was trying to fix an old Dell CRT that had a bad vertical collapse. I spent 45 minutes checking solder joints and tracing the circuit before I noticed a tiny bulge on a 10uf cap near the flyback. My multimeter showed it was still within spec but swapping it out fixed the issue instantly. Has anyone else had a capacitor test good but still cause problems?

2 comments

2 Comments

hall.ruby5d ago

tested good but still caused problems" is the story of my life with caps. Drove me nuts before I learned to just shotgun them all.

charlesj464d ago

Yeah, "tested good but still caused problems" - that phrase has cost me more hours than I care to count. You pop a cap out, check it with the meter, and it reads perfectly fine. Put it back in and the radio still hums like a beehive. I finally figured out that ESR meters are worth their weight in gold for catching those bad ones that look good on a basic capacitance test. Now I just replace any cap over 20 years old on sight, no testing required. Saves time and the headache of chasing ghosts through the circuit board.