The coil currents runs through the rotary output selector switch which connects none/either/both lines to GND. Looks like they get hot for the engaged larger relays, but not the series resistors for the coil for the headphone relay, which are higher resistance 1500 + 1800 Ohm, and thus lower heat loss. Where can I download the Owners Manual for my discontinued Denon model To download a copy of your discontinued models user guide or any other information. I found darkening of the board around the resistors for dropping the voltage (limiting the current) to the relay coils from 50 to 24 V, R639,R640, R641,R642 all of 640 Ohm 1 W, placed very close to each other. The PCB with the speaker relays and speaker terminals (binding posts) can only be removed if the mains transformer is removed or the whole back plate is removed first. But intermittent faults are hard to judge in a short time span. After redoing/re-touching solder joints around the hot resistors and bypassing the selector switch with a solid, soldered short circuit, the fault seems to have went away. Seems to have been loose connections, either in the solder joints near the relays or the rotary switch at the front, or a bit of both. Relays were clicking at random and odd times.
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