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1980 Sansui AU-719 Resistors fried and voltage is down 9 VDC. Check out the cool pic's.

stentis

New Member
This amp is part of a Sansui complete system that was bought in South Korea in 1980. It still belongs to the original owner and he asked if I could check it out after 10 years in storage. As you can see there was a lot of heat damage and trace delaminating plus physical damage. I did a rebuild of the power section, obviously. The OEM resistors were cooked but still functioning but the replacements cooked also. With the two resistors unhooked I am getting low voltage from the bridge rectifier, I removed and checked each component from the fuses to the resistors. The damage on the board was caused by the emitter traces on TR604 and TR612. I need advise on what or how to restore the proper voltages first and then go from there.
 

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    Burned resistors.JPG
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  • Burned Resistos.JPG
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  • Schematic.JPG
    Schematic.JPG
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  • Severe heat.JPG
    Severe heat.JPG
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