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 is a high voltage probe that allows the measurement of high continuous voltages with a common...
The circuit shown in figure is suggested by Texas Instruments (www.ti.com) and makes use of the...
This well-known configuration of the guitar effects pedal was obtained in an English magazine from...