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.
This circuit generates 50, 100 and 200 Hz signals from a 2.2768 MHz TV crystal. The circuit can be...
This small power amplifier makes use of an output transformer given its design time. In fact, the...
This resistance meter with the CA3130 was found in an English publication from 1977. The circuit has...