The shell of a phono jack is grounded and its center conductor goes to the grid, pin 2, of a 12 A X 7. This grid also goes through a 47 k ohm res to ground. The cathode, pin 3, goes through a 2.2 k ohm res to ground. The plate, pin 1, goes through a 220 k ohm res to plus 250 volts. The plate also goes through a .02 mike cap to the other section's grid, pin 7. Pin 7 goes through a 3.3 meg ohm res to ground. The cathode, pin 8, is grounded. The plate, pin 6, goes through a 220 k ohm res to plus 250 volts. Pin 6 goes through a 200 pf cap then a .001 mike cap to pin 3, cathode. There is a 330 k ohm res in parallel with the 200 pf cap. Pin 6 also goes through a .1 mike cap to the center of the output jack, the shell is grounded. End verbal description.
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