Beomaster 900K radio only one speaker working

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Owenski Posted: Mon, Aug 31 2015 8:42 AM

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Hi everyone this is my first post on this forum.

I have a Beomaster 900k radio that seems to have developed a fault with the left hand side speaker channel. At first I thought the left speaker had just died on me as this set still has both of the original speakers in the speaker chambers.

After taking the left speaker out and soldering two wires to it I discovered it was ok after testing it with another radio.

I see there is a little envelope taped to the bottom of the circuit board with a wiring diagram inside it. I am not a expert at fixing radios but I do know my way around inside a radio and can read a circuit diagram and am very handy with a soldering iron & Multimeter.

It took me some time to work out the circuit diagram but when I did I started off with my multimeter measuring the voltages around the two large chassis mounted output capacitors 800uf . The voltage reading from my meter  off these large caps are 10.5volts from one and only 1.6 volts from the other.

This is showing me that there is a voltage problem somewhere on the left hand channel. 

Now I am trying to work out where this fault is coming from?

I suspect it could be a transistor on the small PW board & I am not sure what meter readings I should be looking for to find this fault?

Anyone have any ideas on where the fault could be?

Regards

Owen