Early 1960’s The Fisher 660 stereo receiver was one of Fishers first solid state stereo receivers.  It produced 40-45 watts per channel, the unit is very solid with a couple small repairs to the case and a small bend in the metal grate. (All easy repairs). The unit powers on and I hooked up my iPad to a wireless transmitter and plugged it into the auxiliary input.  Both channels produce sound very weak, when I move the selector knobs it will produce normal loud output.  I believe the selector switches probably will need to be cleaned and it will probably need some caps replaced.  The Fisher 660 is extremely rare, you will probably never see another one.  Again this model is from the early 1960’s not the one in the 1980’s.