Recapping/Repairing Harman Kardon AVR-8500

[pigge]

Hi I've got an Harman Kardon AVR8500 (almost identical electronically to AVR8000, but for 220v)
i had no sound on the right surround channel so i replaced some bad caps, hoping to give this receiver
a new life but to no avail, then i discovered some burnt resistors on the 2ch amp
(Front right and surround right) on the part of the board that was for the surround channel, so i
changed those two resistors as well, but when i had put every thing back together the amp would go in
to auto protect every time i tried to power to amp on. i guess i stressed the amp a bit to much trying to power
it on a couple of times in a row, because after some times pushing the button i could smell burnt
electronics, so i disassembled the amp again and found that the two resistors i changed were burnt again..
I'm thinking it might be a short, but I've checked everything and double checked it and can´t find any
short.. I'm guessing the amp didn't go in to auto protect before since the surround right was broken
end now when it´s not, it does cut power, and that would lead me to believe that a possible short
is most likely to be on the "2ch amp" and on the surround right part of it.

is there any kind of components that when they break will possibly create a short, and that wont show
any signs of being broken visually

 

[alamikam]

Hi,

I have almost the same problem with my AVR 8500, the two resistors are like to burn whenever i push the button. Every component has been double checked but still the problem remain.

I don't know if you have found a technical solution since then , it seems that is a recurrent problem with avr 8500 as i've seen in the net.

Really appreciate your help.

cheers

 

[Vinilemania]

Sono passati molti anni, ma credo che la causa dei resistori che si bruciano sia da attribuirsi ad un cortocircuito dei finali di potenza.
Comunque Harman Kardon Avr 8500 è tra i migliori sintoamplificatori home theatre mai costruiti. 85 Ampere, una centrale elettrica. Tanta potenza erogata con altrettanto controllo che somministra delicatezza ed irruenza laddove occorre.