Question Denon POA-6600A Dead

[123Tmg]

Hello
Thanks for looking
I have a Denon POA-6600A mono amp that is dead, R003 2x resistors in parallel seem to be open circuit on the rear board and the mains transformer seems to measure short circuit although not totally sure. Has anyone had this issue before just to confirm it may be the mains transformer or know where i could obtain a transformer the part number on the side reads = 2339594007
Kind Regards
Tony

 

[MIKEVO]

Tony, I would not recommend trying to fix mains powered equipment, unless qualified to do so.
Many transformers will measure short circuit with a multimeter.
If you have open circuit resistors on the main board, it could be the output transistors have been overloaded, but you need an electronics engineer and a circuit diagram to diagnose the fault.
Even a fully charged power supply capacitor could kill you, mains even worse.

 

[123Tmg]

Hello Mike,
I am unable to find a circuit for this and just wished to know really if there is still any parts out there for such a beast..... No fuses have blown in the unit so im guessing the output stage is fine...
I am an electronics engineer with over 20 years experience before having to move to new ventures, didn't do much in the way of audio as i had far too much work on tv & video
Regards
Tony

 

[MIKEVO]

There is possibly a chap from Norway on the Diy Audio forum that may have a circuit diagram.

With the Power Amp disconnected from the mains, you should be able to measure the output transistors with a multimeter on Diode setting across Base, Emitter and Collector and get some readings that make sense, if you get a short across any of the pins, then they are blown.
You can still get spares, but dry joints and dried out electrolytic capacitors are very common on amps of this age, especially if they run hot, which I think the POA-6600A tends to, if I recall.

The Power Supply in these units runs at +- 80 Volts DC, which is very high for a power amp, plus high current capacitors, so I really wouldn't recommend sticking your fingers in there and I don't wish to get in trouble on the forums as we should not be playing with Mains powered Equipment.
If the Transformer was blown, it would probably look burnt, I doubt its that.

I would join the Diy Audio forum and ask there.

Regards

Mike