TIME_OUT_WARNING

Published:2009/7/20 2:01:00 Author:Jessie | From:SeekIC

Provides either visual or audible warning after preset interval up to 3 min, when pin 1 of first NE555 is grounded by push-to-talk switch on microphone of mobile transmitter. When preset limit is reached, pin 3 provides ground for second NE555 that makes it pulse at 2-Hz rate to warn that time limit for use of repeater is being approached.-F. Sharp, Time-0ut Warning, QST, 0ct. 1976, p 67.



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