This circuit was found in the September 1992 issue of Radio Electronics magazine. The circuit does not use a transistor to drive the relay and has no adjustments.
This circuit was obtained from the Radio Electronics magazine of April 1991. The circuit is based...
This experimental good sensibility radio was obtained from a 1968 magazine. The magazine no longer...
s. In it, a set of batteries or battery provides the reference voltage for the output. The...