Triode power amplifier. The input terminal goes to the top of the volume control 500 k ohm audio taper. The bottom end is grounded. The wiper goes through a .1 mike capacitor to the grid, pin 7 of a 12AX7. The grid goes through a 470 k ohm res to ground. The grid is labeled 73 millivolts AC. The cathode, pin 8 goes through a 1100 ohm res to ground. The plate, pin 6, goes through a 270 k ohm res to B+ 4. The plate also goes directly to the grid, pin 2, of the other section. The cathode, pin 3, goes through a 100 k ohm to ground. The cathode also goes through a .1 mike cap to the grid, pin 7, of a 12AU7. The plate, pin 1, goes through a 100 k ohm to B+ 4. The plate also goes through a .1 mike cap to the grid, pin 2, of the 12AU7. Each grid of the 12AU7 goes through its own 470 k ohm res to ground. Each cathode, pins 3 and 8, goes through its own 6.8 k ohm res to ground. Each plate, pins 1 and 6, goes through its own 100 k ohm res to B+ 3. The plate, pin 1, goes through a .1 mike cap to the grid, pin 1, of a 6SN7. The other plate of the 12AU7, pin 6, goes through another .1 mike cap to the grid, pin 4, of the 6SN7. One cathode of the 6SN7, pin 3, goes through a 2.7 k ohm then another 2.7 k ohm res to ground. The junction of the two resistors goes through a 470 k ohm res to the grid, pin 1. In a similar way the other cathode, pin 6, goes through two 2.7 k ohm resistors to ground with a 470 k ohm going from the junction to the grid, pin 4. Each plate, pins 2 and 5, goes through its own 47 k ohm 1 watt res to plus 500 volts. The plate, pin 2, goes through a .01 mike cap to the grid, pin 1, of a 6AS7G. The other plate of the 6SN7 goes through another .01 mike cap to the grid, pin 4, of the 6AS7G. The cathodes, pins 3 and 6, are tied together and go through a 1.25 k ohm 20 watt resistor to ground. A note states that this resistor is made up of 4, 5 k ohm 5 watt resistors in parallel. One plate, pin 2, goes to the blue lead of the output transformer primary. The other plate, pin 5 goes to the brown lead of the transformer primary. The red, center tap, goes to plus 400 volts. No, that's not a miss print. The driver plates have more B plus than the output plates. The black lead of the secondary is grounded and the yellow lead goes to one end of a 15 k ohm res and an unlabeled capacitor in parallel. The other end of this parallel combination goes to the cathode, pin 8, of the 12AX7. There is an 8 ohm 50 watt resistor connected across the output transformer secondary. A 10 k ohm resistor connects from plus 500 volts to B plus 3. There is a 40 mike 500 v cap connected from B plus 3 to ground. There is a 68 k ohm res from B plus 3 to B plus 4. There is a 20 mike 450 v cap from B plus 4 to ground. End verbal description.
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