PTT or Push to Talk is the control that switches the speak-hear function on a transceiver. This circuit was found in the magazine of radio amateurs 73, in an edition of the 90s.
This is a simple 1-digit voltmeter circuit using voltage comparators. It was found in a 2004...
This circuit is from old documentation, but the regulator may be 78xx series equivalent and the...
This circuit appeared in the November 1995 issue of Electronics Now magazine. The circuit uses...