Hi, several years ago I bought a new Harman Kardon AVR 335 receiver. I listened to it for about a month and bought something else. I put it back in the box and it stays like that for several years. Recently I decided to put it in the garage but something is wrong with it. It powers up, everything on the display works fine but no sound on the speakers. I will open it in the next few days to check it. But wanted to ask for some advice as to what it could be, the fault is obviously caused by staying in the box for several years. Thank you
Hugely complex piece of kit. First advice would be to ensure you have it configured correctly before suspecting a genuine fault.
Fair enough 🙂
So you are down to basic fault finding using a scope and signal source and following the signal path through the amp... which without a full circuit diagram will be next to impossible I'm afraid.
You can try and split the problem in two and see if audio is reaching the power amp stages. That should be possible without a circuit but it it would be a case of having to visually identify various parts of the circuit and then figure out where the input would be applied.
So you are down to basic fault finding using a scope and signal source and following the signal path through the amp... which without a full circuit diagram will be next to impossible I'm afraid.
You can try and split the problem in two and see if audio is reaching the power amp stages. That should be possible without a circuit but it it would be a case of having to visually identify various parts of the circuit and then figure out where the input would be applied.