This oscillator was found in the January 1987 issue of Radio Electronics magazine. The frequency is adjusted by C1, and the output has good symmetry. The power supply is typically 3 to 12 V.
This low current parallel or shunt type regulator was found in documentation from the 60's. The...
This circuit is found in a 1975s documentation for radio amateurs. It was developed to recognize a...
The displayed relay operates with an audio signal applied to the input. The transistors can be...