This is an R F final amplifier with a collector modulator. The emitter is grounded. The base goes to a point labeled R F drive. The base also goes through an R F choke to ground. The collector 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 V C C 1. The V C C 1 point goes to the center tap of the primary of the modulation transformer. Each end of the primary connects to the collector of another transistor. These are the modulator transistors. The base of each transistor goes to one end of the secondary of the audio driver transformer. The emitters of the modulators are grounded. The center tap of the secondary goes to a point labeled bias. One end of the primary goes to a point labeled V C C 2 and the other end goes to a point labeled audio drive. Returning to the collector of the RF transistor, 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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