Figure 15 Williamson Circuit With Balance Control and no First Stage Bootstrapping. B plus points. The plus 400 volt point is bypassed to ground through a 47 u f 450 volt capacitor. The 400 volt point connects through a 2.7 k ohm resistor to B plus 2. B plus 2 is bypassed to ground through another 47 u f 450 volt capacitor. B plus 2 goes through a 4.7 k ohm resistor to B plus 3. B plus 3 is bypassed to ground through yet another 47 u f 450 volt capacitor. The hot input terminal goes through a 0.015 u f capacitor to the grid, pin 1, of V 1 eh, 6SN7. The grid also goes through a 470 k ohm resistor to ground. The cathode, pin 3 goes through a 1.5 k ohm then a 1 k ohm resistor to ground. The junction of the two resistors goes to a point labeled g n f b. There is a 220 u f 15 volt capacitor in parallel with the 1.5 k ohm resistor. The plate, pin 2, goes through a 68 k ohm than another 68 k ohm resistor to B plus 3. V 1 eh plate, pin 2, goes directly to V 1 b grid, pin 4. The cathode, pin 6, goes through a 68 k ohm resistor then a 5 k ohm pot to ground. The wiper of the pot is connected to ground. The cathode also goes through a 0.1 u f capacitor to the grid, pin 1, of V 2 eh, second 6 S N 7. The plate, pin 7, goes through a 68 k ohm resistor to B plus 2. The plate also connects through a 0.1 u f capacitor to the grid, pin 4, of V3 b,6 S N 7. Pin 4, grid of V 2 b connects through a 1 meg ohm resistor to ground. Pin 1 of V 2 eh connects through another 1 meg ohm resistor to ground. The cathodes of V 2, pins 3 and 6, are tied together and go through a 4.7 k ohm resistor to ground. The plate, pin 5 of V 2 b, goes through a 100 k ohm then another 100 k ohm resistor to plus 400 volts. The junction of the two resistors goes through a 10 u f 450 volt capacitor to the cathode, pin 3 of v 3 eh. There is a 0.033 u f capacitor in parallel with the 10 u f electrolytic. The plate of V 2 eh, pin 2, goes through a 100 k ohm then another 100 k ohm resistor to plus 400 volts. The junction of the two resistors goes through a 10 u f capacitor to the cathode, pin 6 of V 3 B. There is a 0.33 u f capacitor in parallel with the 10 u f electrolytic. The plate, pin 5 of v 2 b, connects directly to the grid, pin 1 of V 3 eh. The other plate, pin 2 of V 2 eh, connects directly to the grid, pin 4 of V 3 b. The cathode of V 3 eh, pin 3, goes through a 47 k ohm 1 watt resistor to ground. The cathode of V 3 b, pin 6 goes through another 47 k ohm 1 watt resistor to ground. The cathode of V 3 eh, pin 3, goes through a 0.1 u f capacitor to output 1. The cathode of V 3 b, pin 6 goes through another 0.1 u f capacitor to output 2. Output 1 goes through a 100 k ohm resistor to ground. Output 2 goes through a 100 k ohm resistor to ground. This completes the description of figure 15.
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