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Harman Kardon ; strange value of voltage

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  • Harman Kardon ; strange value of voltage

    Hi,

    After the schematics (power supply zone) ; instead to have +35.6v for Q5 2SD669 and -35.6 v for Q6 2SB649 i have 42v and -42v ! For the rectifiers bridges i have 44.8v and -44.8v for both...

    Also the heatsink of q5 and q6 are very hot...

    Is there someone who spot it too ?

    Just for information i just found an issue for the mega loud pop on bass contour switch... In fact the switch were out ; but even with new switch it was loud too ! So i changed the 2 caps c507 and c508 10uf/50v by 10uf 50 wima and c901 /c902 by 100nf/100v non electrolytic caps... And no more loud pop... I saw somewhere on the web, it was a common mistake for pm655 and certainly a mistake in the circuit...because we have c901/c902 in electrolytic mode were ground of each cap were not connected to ground ! So leakage currents can thus charge one side of the electrolytic capacitor and then generate this loud pop !

    Thanks in advance
    Cheers
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