This is an R F final amplifier with plate modulator. The R F tube is a filament type. There is a capacitor connected from each side of the filament to ground. Each side of the filament goes to one side of the secondary of the filament transformer. The center tap of the secondary is grounded. The control grid goes to a point labeled R F drive. The grid also goes through an R F choke then a resistor to a point labeled bias. The junction of the R F choke and resistor is bypassed to ground by a cap. The screen grid goes through a cap to ground. It also goes through a resistor to point A. The suppressor grid is grounded. The plate goes through an R F choke to point A. There is a cap from point A to ground. Point A goes through the secondary of the modulation transformer to a point labeled H V. The H V point goes to the center tap of the primary of the modulation transformer. Each end of the primary connects to the plate of a heater type pentode tube. These are the modulator tubes. The H V point goes through a resistor to the screen grids of both modulator tubes. The screens go through a cap to ground. The suppressor grids and cathodes are grounded. The control grid of each tube goes to one end of the secondary of the audio driver transformer. The center tap of the secondary goes to a point labeled bias. One end of the primary goes to a point labeled B plus and the other end goes to a point labeled audio drive. Returning to the plate of the RF tube, it goes through a cap to point C. Point C goes through a variable cap to ground. Point C goes through an inductor to point D. Point D goes through another variable cap to ground. Point D goes through an R F choke to ground. Point D goes to the center of the antenna connector. The shield of the connector goes to ground. End verbal description.
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