I used my Harman Kardon receiver for many years until it suddenly "died" whilst in use, that is the sound suddenly faded out.
On inspection I found several burnt components on a power supply board CUP11581-5 including a transistor and with the help of the manual (available on the web) was able to identify all of them and so was able to get the receiver running again.
Later on the Optical digital inputs failed to operate (all three of them, two on the back and one on the front). It is important to have one of these working as an input from the TV as there are no HDMI connections on the receiver. The connectors don't light up as they should although the output Optical does. The matching Co-axial digital connectors, on the same board, do work. The board is CUP 11581 - 3.
I have reset the processor with no result. As there are no obvious faults, I am wondering if there is a software fault.
Any ideas please?
On inspection I found several burnt components on a power supply board CUP11581-5 including a transistor and with the help of the manual (available on the web) was able to identify all of them and so was able to get the receiver running again.
Later on the Optical digital inputs failed to operate (all three of them, two on the back and one on the front). It is important to have one of these working as an input from the TV as there are no HDMI connections on the receiver. The connectors don't light up as they should although the output Optical does. The matching Co-axial digital connectors, on the same board, do work. The board is CUP 11581 - 3.
I have reset the processor with no result. As there are no obvious faults, I am wondering if there is a software fault.
Any ideas please?