Shelving Treble cut. On the left is an input terminal which connects to the grid of a triode, 12 A X 7. The grid goes to ground through a 470 k ohm resistor. The cathode goes to ground through a 1.8 k ohm resistor. The plate goes to B plus two through a 100 k ohm resistor. The plate also connects to one end of a 0.1 microfarad capacitor. The other end goes to the top of a 470 k ohm resistor. The bottom end is grounded. The junction of the 0.1 cap and the 470 k ohm resistor would go to the grid of the following stage although it is not shown. This point connects through a 0.0022 microfarad cap then through a 10 k ohm resistor to the top of a 500 k ohm pot. The bottom end is grounded. The wiper connects to the top of the pot making it a rheostat. End verbal description.
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