by Record-changer »
Fri Nov 03, 2006 8:09 am
The tubes are:
6AQ5A Power amp (That's an A, not a 4)
12AX7 Dual preamp (two amps in one package)
6X4 Power supply.
Some possible causes:
- The pickup cartridge has failed. Crystal and ceramic cartridges absorb moisture and fail over time.
- Oxidized tube pins not making contact.
- Half of the 12AX7 is weak,
- Half of the 12AX7 filament burned out. There are two filaments in the tube, They are wired in parallel for 6 volts, or in series for 12 volts. Your other tubes are 6 volts, so the 12AX7 filaments are probably in parallel.
- One speaker is bad.
- Other components for the 6AQ5 or 12AX7 circuitry faiked. Check the values of the resistors.
- Shorted coax.