Simple, easily transported VSWR meter consists of high-gain amplifier, narrow-bandwidth (100-Hz) selective amplifier tuned to 1000 Hz, and variable-gain output amplifier driving low-cost VU meter. Ideal for nulling type VSWR measurements. Draws only about 6mA from 9. V transistor battery. Closing S1 increases gain about 100 times for Iow. Ievel read

ings. R1 sets U1B to 1000 Hz, while R2 sets reference on VU meter. -J. Reisert Matching Techniques for VHF/UHF Antennas, Ham Fladio, July 1976, p50-56.

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