SCANNER_SILENCER

Published:2009/6/23 4:38:00 Author:Jessie | From:SeekIC

When a scanner is used at amateur radio or CB stations, the scanner sometimes picks up trans-mitted signal and howls or squeals. When RF is detected, Q1 tums on, energizing K1 and discon-necting the scanner speakers. SO1 is connected to the transmit antenna lead via a tee fitting. C1 is optimum for 5- to 10-W 30-MHz use. For higher power or higher frequencies, reduce C1 to as low as needed. If C1 is so small as to be impractical, R1 can be shunted with a 10- or 22-pF capacitor, as needed.



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