Pioneer A-209R Amplifier Repair

Fault 1 Amplifier would not power up Primary of the transformer checked and found to be open circuit. Replacement Toroidal transformer fitted secondary rating 26V-0-26V 70VA. Amplifier retested and power up, bias set for each channel to 10 millivolts. Functional test made and a second fault was identified. The input selector would indicate the correct selected input on the front panel, but the actual signal switched through could often be random, also the direct selection could not be switched off. CPU PD5443A Pioneer had to be replaced, the IC is located on the front panel PCB. Amplifier fully tested correct operation