I bought this amp on ebay as non working. Got it with only 6 screws holding the thing together. So i went to my local hardware shop and picked up a new set. I went ahead and cleaned the thermal compound and reapplied new between the black fins and the chassis.
I notice the amp has been repaired before because all the transistors have new solder. There are signs of blown fets in the power supply. Also only 2 gate resistors where replaced (smd ), don't know why they didn't replace all if them.
Well after powering the amplifier i got output. And after a few minutes of sine waves and a few bass tester tunes the amplifier was cold to the touch even after 30m of play. Then when i slightly wiggle the rca's to see if it was loose or had problems with i got i tiny shock. So i used my dmm and measure the voltage between the chassis and the rca's and i had 84.4vdc and -84.4vdc when i switch the test leads.
Any help appreciated.
I notice the amp has been repaired before because all the transistors have new solder. There are signs of blown fets in the power supply. Also only 2 gate resistors where replaced (smd ), don't know why they didn't replace all if them.
Well after powering the amplifier i got output. And after a few minutes of sine waves and a few bass tester tunes the amplifier was cold to the touch even after 30m of play. Then when i slightly wiggle the rca's to see if it was loose or had problems with i got i tiny shock. So i used my dmm and measure the voltage between the chassis and the rca's and i had 84.4vdc and -84.4vdc when i switch the test leads.
Any help appreciated.
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The only components that got warm where the rail caps and the transformers. But the heat sink was cold. My only guess would be a damaged mica insulator between a transistor and the sink, that's causing the voltage between the rca jack and the chassis.
The out put rcas don't have this problem, only the input.
The out put rcas don't have this problem, only the input.
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Sweet, Perry you are the man. Found out after removing the hold down clips that the who ever repaired it left the output transistors mounted to high so their toxin the clips themselves. Will lower them and retest.
Any idea where i can find those clips?? Seems like whoever did the repairs couldn't keep up with small amount if screed and parts, go figure. They made a ghetto clip, lol.
Any idea where i can find those clips?? Seems like whoever did the repairs couldn't keep up with small amount if screed and parts, go figure. They made a ghetto clip, lol.
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