Question about Adcom GFA-5500 2-Channel Amplifier

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My adcom gfa5500 .most of its output mosfets are shorted.

I m able to get the output mosfets. BUT,when i check other components,i found out the value of R 23 of the left channel is different from the rigt one.since i dont have the schematic.i neeeeed help!!!!

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  • Scott Frye
    Scott Frye May 11, 2010

    Hi...

    I have the diagrams for the MarkII
    What is R23 connected to?
    I can cross it to my docs.
    Thanks

    Also, ADCOM gave me free docs.
    Ask them nicely and they'll get you some.


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I give you the schematic

Posted on Jun 25, 2015

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The colour code or the value it states on R23 should give you the reading you will see on a test meter on the Ohm setting. If the value doesn't match the colour code of the resistor then you should replace it. It's best to take any resistor out of the circuit to test as strange readings can be caused in circuit. The same applies to the left channel one. Ohm meters are not expensive if you don't have one and can be got from various places that sell electronics parts etc. Some car part dealers sell them. They are a worthwhile investment and can be used for many types of problem.
It's likely that it's a basis resistor and failed when the power jobs went.

Posted on Oct 22, 2009

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