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 Sample & Hold circuit uses infrequent field effect transistors today and an operational one that...
With an op amp with FET, this 1977 circuit uses an LDR as a sensor and drives a relay. The relay...
This 12 V incandescent lamp switch with time delay can be found in old documentation. The SCR can...