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I'm an electronic technician so I have a little experienece with power supplies, etc, but electronic keyboards is NOT my strong point. My A-33 appears to be destroying power supplies as soon as I plug them in. No smoke, smell etc, they just stop putting out 9V DC (center tap)when measured w/my meter. Any ideas, particular what resistance should I be seeing at Rolands' input with the A-33's power switch on and off. No power supply plugged in during measurements, of course. Thanks! Tom Adams

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If you know what the normal amperage is during use,you can obviously figure it out using the volt,current,resistance,formula.If you do not know the normal amperage,I think power supplies are rated to be used at about 50%(I am sure they are not made to run at 100% for the long times necessary),so if the output is listed on the power supply,that is a reference(with the power supply output,you probably know the rate,percentage better than I do).If you are not 100% sure about the stuff I suggested,I would call the maker and see what they are willing to tell you at least.Just giving you an outside the box perspective.Good luck and let me know how you make out!

Posted on Aug 05, 2010


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