This circuit was obtained in a Electronics World of 1968. The transistors can be equivalent as the BC558 for the PNP and the BD135 for the NPN powering lamps from 3 to 12 V according to the supply.
We found this circuit in a 1978 documentation. The SCR conducts when the regulator's output...
This circuit, from an old 1988 publication, generates bars on the screen of an old analog TV for...
This circuit triggers by choosing the higher of two voltages. The circuit is from a 1964...