The power supply section. The wide prong of a 2 wire cord goes to the circuit common, not, repeat, not, the chassis. The narrow prong goes through a 1 half amp fuse then the on/off switch to pin2, one side of the heater of a 117L7/M7 tube. This tube is a combination half wave rectifier and beam power amplifier. The other side of the heater, pin 7, goes to circuit common. Pin 2, the hot side of the line, goes to the plate, pin 6 of the diode. The cathode, pin 1, goes to the positive side of a 40 mike 150 volt cap the other side goes to circuit common. The diode cathode also goes through a 1 k ohm 2 watt res to the positive side of another 40 mike 150 volt cap. The negative side goes to circuit common. There is a 22 k ohm 2 watt res in parallel with this last cap. The positive of the second cap goes to the positive DC output. The Negative DC output goes to circuit common. The DC output terminals are labeled 140 volts no load, 110 volt at 30 mA. The circuit common connects through the parallel combination of a 100 k ohm res and a .001 mike cap to the chassis. The amplifier section. The lower input terminal goes to circuit common. The upper one goes through a .01 mike cap to the grid, pin 4, of the beam pentode section of the tube. The grid goes to circuit common through a 470 k ohm res. The cathode, pin 8, goes through the parallel combination of a 150 ohm res and a 25 mike 25 volt cap to common. The suppressor grid is internally connected to the cathode. The screen grid, pin 5, goes to the output of the power supply. The plate, pin 3, goes to the blue lead of the output transformer, one side of the primary. The other side of the primary, red goes to the cathode of the rectifier diode., pin 1. The speaker connects to the secondary and one side of the speaker goes to chassis ground. The output transformer is a 5000 ohm to voice coil. End verbal description.
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