This circuit was obtained in a 1982 English magazine. The purpose of this circuit is to interface signals other than TTL circuits with TTL inputs. The transistor can be a BC548, 2N2222 or any equivalent.
This 2-quadrant modulator circuit was found in the May 1988 issue of Radio Electronics magazine. The...
This circuit was obtained in documentation from the 1980s. The triac and the unijunction support...
This circuit uses unijunction transistors and drives a small speaker through an output...