This basic circuit was found in the March 1998 issue of Electronics Now magazine. The circuit is powered by 2V and uses a 28 MHz crystal or resonator.
In the figure we have the adapter circuit for connecting a headphone to the output of a stereo...
Found in the June 1972 issue of Radio Electronics magazine, this circuit generates signals that...
The output of this circuit must be connected to the input of an audio amplifier. The microphone is a small...