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Hoffman Amps Forum image Author Topic: Ampeg SVT-3PRO blowing .125ma fuses  (Read 5830 times)

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Offline punkykatt

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Ampeg SVT-3PRO blowing .125ma fuses
« on: February 27, 2009, 01:09:49 pm »
Hello guys, A friend of mine has a Ampeg SVT-3PRO base amp thats blowing the 1/8th amp slow blow fuse located in the a/c HT PS line just before the rectifier, only when the amp is turned on. When I bring it up with the varivac it works fine.  All the voltages look good except off the "A" node after R9 (56k tested good) the voltage was 30% below schematic specs as well as the down stream test points TP2, 3, 4, and 7.  Is it possible the filter cap C5 is partially shorted?  Any help and suggestions are much apperciated.  Punky
Sorry!!! the schematic I have is too big to post here.  Please E-mail me sbuczko(AT) comcast.net and I will send you the schematic.
« Last Edit: February 27, 2009, 01:14:59 pm by punkykatt »

Offline punkykatt

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Re: Ampeg SVT-3PRO blowing .125ma fuses (Resolved)
« Reply #1 on: March 01, 2009, 11:03:15 am »
Me big Dummy.  I thought I ordered the slow blow fuses. I put down the wrong part number when ordering and got fast acting.  :o ::)  :P ;D

 


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