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cashewcupcake 11th February 2003 05:20 PM

microphonic cables and squealing
Howdy doody? This isn't really a design post, but I wondered if one of you real engineers could help me out.

The DIs in my rack have a ground loop hum, and any cables plugged into them are EXTREMELY microphonic. When I plug a connector halfway into the jack, it SQUEALLLLLS.

Something seems really wrong. Got any reccomendations?


Dailydb 12th February 2003 10:12 PM

very sorry, but I'm not sure I can help without getting my hands on them.......there's just too many possible variables.

Can you get them to a good tech near you ? or send 'em over here ?


littlelabs 12th February 2003 11:15 PM

Hey Fae Flora,
Try pulling them out of the rack first to eliminate the rack rail. Are they active or passive? Something is feeding ground and back on itself making an oscillator. Isolate isolate then isolate again! More details as Allan says is necessary to diagnose properly.