The purpose of this circuit is to measure the resistance of an antenna at the resonant frequency. The circuit is from an old American documentation for hams.
Suggested by an American technical documentation, this circuit is polarized in order to provide an...
This modulated siren was found in the December 1974 issue of Radio Electronics magazine. A higher...
This circuit with 5 times gain was found in European documentation from the 1980s. The input and...