TIL my $400 power supply was killing my repair jobs

I kept having boards die on me after I fixed them. Turned out my bench power supply was putting out dirty voltage with like 150mV of ripple. Found a video from a repair shop in Denver that tested cheap supplies. Mine was a TekPower from Amazon I bought 2 years ago. Swapped to a used HP supply off eBay for $80 and now my repairs actually hold. Anyone else get burned by a crappy bench supply?

2 comments

2 Comments

sarahh487d ago

Your bench power supply was putting out dirty voltage with like 150mV of ripple" - that's actually a brutal oversight but not one that gets talked about enough. I mean, people spend all this time obsessing over fancy soldering irons and microscopes but totally ignore the power source. It's like having a clean water filter but drinking from a rusty pipe, you know? What gets me is how many brand new supplies are basically just rebranded cheap Chinese transformers with zero filtering, and reviewers on Amazon don't have the gear to test them properly. I swear half the time when someone says "my repair didn't hold" it's probably the supply, not their soldering.

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elliot_miller227d ago

Funny you mention that, I once spent two weeks chasing a weird glitch in a microcontroller project. Turned out my bench supply had a failing cap that was dumping 200mV of trash into the power rail. Spent all that time debugging code and swapping sensors, never once checked the power source. Felt like a total idiot when I finally threw a scope on it. But you're right, nobody talks about that part of the hobby. Its like we all assume the wall outlet just magically delivers perfect DC or something.