This circuit was obtained in an American documentation from the 80's. The transistors can be equivalent to those indicated and the crystal can reach a few tens of megahertz.
The circuit presented is from a 1972 RCA technical documentation. The integrated circuit consists of a...
This circuit is from a 1967 publication. The configuration holds true for modern transistors having...
This proximity relay circuit was found in the July 1990 Radio Electronics magazine. The supply...