ADD_ON_S_METER

Published:2009/6/30 21:21:00 Author:May | From:SeekIC

Although designed for use with Clegg FM-27B 2-meter FM receiver, circuit can be readily adapted to other receivers. Am-plifier brings low-level455-MHz IF signal up to level suitable for driving meter. For other IF, such as 10.7 or 11.7 MHz, capacitor values should be changed accordingly. Any NPN tran, sistor with beta of 30 or more at IF value can be used. Diodes can be any type. Supply should be regulated but can be 7-14 V. Output of diode detector will vary from 0 to 1 V at nominal impedance of 20K; for best result, meter with 20- to 50-μA movement can be used.-M. Stern, FM-27B S-Meter, QST, Doc. 1976, p 35.



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