hifi engine

kenwood kr 4070 receiver (schematic)


I have a KR4070 with the complain that sometimes when switched on the audio is missing but the indicators's are ok.So I think the powerswitch is ok.I found that the muting can be triggerd with Q21 where the base is very sensitive .Measuring with a multimeter to gnd triggers the mute.

So tips or better a schematic would help me.I was also supprised to see some printed resistors on the upperlayer.

Pioneer SA-9500

Thanks very much for the tech data for this grand old machine. I have no doubt it will be the key to running down the "hum" being produced by the input &/or control amp cktry.