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See Section 254
No Sound   Switches or rheostats on amplifier rack set incorrectly. Set switches and rheostats to their correct positions.
Amplifier tubes and exciter lamps fail to light. Fuse blown in 15 volt generator circuit. Replace fuse. If fuse blows again check for short-circuit on the "A" supply line. See section 247.
Tubes of one power amplifier unit fail to light when those of other do light. Defective lever switch on power amplifier panel. Operate with the amplifier which is O.K.
Tubes of power amplifier light but no reading is obtained on the plate current milliammeters. Open in the 1000 volt generator circuit. Burned out fuse in the 1000 volt circuit. Replace burned out fuse. If the fuse blows again open both lever switches on the power amplifier panels, replace the fuse and close lever switches one at a time. If the fuse blows when one of these switches is closed, the indication is that there is a short-circuit in the power amplifier associated with the switch.
Operate with the other power amplifier alone. Replace the tubes in the defective power amplifier, and check operation when convenient.
All amplifier tubes light. No reading at the EB123X100. Fuse blown in 500 volt circuit. Replace burned out fuse. if the fuse burns out when replaced, replace all the tubes of the voltage amplifier and replace the fuse in the 500 volt generator again.
Noise or Hum Hum from the monitor and stage speakers.Dirt and acid on top of the storage batteries. Clean storage batteries.
Fuse blown in battery circuit. Replace the fuse.
Reverse current relay stuck open. Notify the RCA service engineer.
Storage batteries gassing. Decrease charging rate of the storage battery.
Dirty commutators on the generators of the M-G set. Clean the commutators. See section 36.
Hum from the monitor only. See "Hum" section 259.  
Whistling Sound.Readings fo the plate current meters on the power amplifier panels not equal. Plate currents of power amplifier tubes not properly adjusted, or defective tube. Balance readings if possible. Replace the tubes if balancing is not possible, or does not eliminate the noise. See section 183.


Chapter Fourteen Pages
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