Figure 8 Williamson Circuit Less Power Outputs. The hot input terminal goes through a 0.1 u f capacitor to pin 7, the grid of a triode which is labeled one half 12 eh Y 7. The cathode, pin 8, goes to the top of a 5 k pot, P 1. The wiper is tied to the bottom and they go through a resistor to ground. The resistor is labeled capitol r, small k, and there is a note saying, see table 7. The top of the pot also goes to the positive end of a 470 u f 25 V capacitor. The negative end goes to the junction of the lower end of the pot and the resistor. The grid also goes through a 1 meg ohm resistor to the junction of the pot and resistor in the cathode. The same junction goes to a point labeled G N F B which stands for global negative feedback. The plate, pin 6, goes through a 100 k ohm resistor then a 270 k ohm resistor to a point we will call B plus 2. The plate of the first triode also goes directly to the grid, pin 7, of the second triode one half 6DJ8. The cathode, pin 8, of this triode goes through a 47 k ohm 1 watt resistor to ground. The cathode also goes through a 1 u f capacitor to the junction of the 100 k ohm and 270 k ohm resistors in the plate of the first triode. The cathode also goes to a point labeled T P 1 which stands for test point 1. The plate, pin 6, goes through another 47 k ohm 1 watt resistor to B plus 2. The plate also goes through a 1 u f capacitor then a 330 k ohm resistor to the junction of the pot and resistor in the cathode of the first triode. The plate also goes through a 0.1 u f capacitor to the grid, pin 2, of the top triode in a 6CG7. The cathode goes through another 0.1 u f capacitor to the grid of the lower triode, pin 7, of the 6CG7. The grid of the upper triode, pin 2, goes through a 1 meg ohm resistor to the wiper of a pot, P 2, 5 k ohms. The lower grid, pin 7, goes through another 1 meg ohm resistor to the wiper of P 2. Both cathodes of the 6CG7, pins 3 and 8, are tied together and go to the top of P 2. The bottom of P 2 goes through one resistor then another resistor to ground. Both resistors are 5.6 k ohm 1 watt. The plate of the upper triode, pin 1, goes through a 33 k ohm 2 watt resistor to plus 400 volts. The plate of the lower triode, pin 6, goes through another 33 k ohm 2 watt resistor to plus 400 volts. The plate of the lower triode goes to a point labeled T P 2. The plus 400 volt point goes to a point labeled T P 3. The plate of the upper 6CG7 triode, pin 1 goes through a 0.1 u f capacitor to output 1. The lower 6CG7 plate, 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 another 100 k ohm resistor to ground. B plus 2 is bypassed to ground by a 100 u f 450 volt capacitor. A 1 k ohm resistor connects between B plus 2 and plus 400 volts. The plus 400 volt point is bypassed to ground by another 100 u f 450 volt capacitor. This completes the description of figure 8.
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