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Chat with an older tech changed how I check ground loops
I was working on a 172 in the hangar last Tuesday and this old timer named Jerry came by. He saw me using my DMM on a PTT circuit and said I was wasting time checking resistance instead of voltage drop under load. He showed me how a 0.2 volt difference across a ground wire can cause all kinds of intermittent issues. Never thought about it that way before but now I check voltage drop first every time. Has anyone else switched up their troubleshooting approach after a tip like that?
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claire_ramirez2214d ago
Oh man, Jerry sounds like the kind of guy who has a tool for everything and a story for every tool. Bet he's been fixing planes since before they had glass cockpits. I swear half the "new" troubleshooting methods are just stuff old timers forgot to tell us the first time around. Now I'm gonna be that guy checking voltage drops on everything too. Thanks Jerry, I guess.
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holly_gonzalez6114d ago
Lmao you're so right about the "new" troubleshooting being old stuff recycled. I once spent three days chasing an intermittent avionics glitch on a King Air, finally found it was a corroded ground strap hidden behind a panel. Jerry's voltage drop trick would have saved me a solid 12 hours of head scratching. Ever since that job, I throw a multimeter on every ground connection I touch, even if it looks clean.
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