Hi guys, I have this AVR-X500. It has no audio output but if I select some input (DVD) and connect an audio signal to the RCA DVD inputs, I hear a relay click and sometimes there is a slight crackling on the speakers.
I only have 2x 8ohm speakers attached to Left and Right front.
If I plug headphones in, the crackling noise stops but I get no audio on the headphones.
I checked the voltages marked on the connectors on the Preamp PCB (12V, 5V etc) and they are all present. There is also plus/minus 56V on the bridge rectifier on the main amplifier PCB (referenced to chassis)
With a scope I can see I have audio input coming into the amplifier on the DVD RCA connectors but I have no audio output on the ribbon from the preamp PCB to the main amp PCB. Again these are marked on the PCB (FL,SL,CEN,SR,FR).
The front panel display and buttons seem to work OK
So the problem appears to on the preamp board. Any suggestions? Anyone have a schematic or service manual? Thanks
PS Looks like the audio inputs go via a NJU72340A IC and I found a datasheet so that could be a place to start if no schematics available
I only have 2x 8ohm speakers attached to Left and Right front.
If I plug headphones in, the crackling noise stops but I get no audio on the headphones.
I checked the voltages marked on the connectors on the Preamp PCB (12V, 5V etc) and they are all present. There is also plus/minus 56V on the bridge rectifier on the main amplifier PCB (referenced to chassis)
With a scope I can see I have audio input coming into the amplifier on the DVD RCA connectors but I have no audio output on the ribbon from the preamp PCB to the main amp PCB. Again these are marked on the PCB (FL,SL,CEN,SR,FR).
The front panel display and buttons seem to work OK
So the problem appears to on the preamp board. Any suggestions? Anyone have a schematic or service manual? Thanks
PS Looks like the audio inputs go via a NJU72340A IC and I found a datasheet so that could be a place to start if no schematics available
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