AN IMPROVED CRYSTAL-CONTROLLED PRESELECTOR AND I-F AMPLIFIER FOR 225-400 MC RECEPTION

摘要

The development of a 10-channel, crystal-controlled receiver (Model XCS-1) to provide performance superior to that of the Model RDZ equipment in the 225- to 400-megacycle range is described; and problems involved in the development of improved variable-tuning capacitors, a thermostatically controlled crystal turret, the crystal-controlled oscillator-multiplier system, the signal-frequency and the converter circuits, and the intermediate-frequency transformers are discussed. The performance characteristics of Models X-RED, CHXY, and XCS-1 prototype equipments are dis¬cussed, and recommendations made for improvements over the original designs.