Published:2009/7/1 21:52:00 Author:May | From:SeekIC
Millen 90652 solidstate grid-dip oscillator uses MOSFET operating in split-Colpitts circuit with resonating tank connected between drain and gate. Circuit is tuned by split-stator variable capacitor with rotorgrounded, chosen to cover 1.7 to 300 MHz with seven plug-in coils. Oscillator also functions as Q multiplier that increases sensitivity.RF voltage across tuned circuit is indicated by meter whose reading dips for resonance with coupled test circuit. Full-wave rectifier CR1-CR2 provides DC voltage for meter and some overload protection for MOSFET. Meter is suppressed-zero type, with readings only for upper portion of current range. J3 is provided for use with low-frequency coils.-W. M. Scherer,CQ Reviews: The Millen Model 90652 Solid-State Dipper, CQ, Sept. 1971, p 63-64, 66, and 96.
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