260. PG-2 EQUIPMENT TROUBLE CHART See Section 254
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Trouble | Indication | Cause | Remedy |
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. |