I have acquired a Fisher 440-T unit that had initially low output on almost everything. After replacing numerous 1uf coupling caps on the preamp and tone boards, I have adequate output except for low audio one just the left channel of FM. The selector switch makes no difference but the Mode switch will balance things out. My search online found a schematic for two versions of the unit, but unfortunately mine uses a different MPX decoder board than either schematics I've found. the serial number on mine is 64574D.
Any direction on where to look next is appreciated.
Any direction on where to look next is appreciated.