This balance control for the channels of a stereo system was found in a 1969 Mullard documentation. The transistors may be the modern BC548 equivalents.
Employing a unijunction and a triac of the era, this 1964 Electronic Design circuit uses a diac to...
This configuration, obtained from a 1973 publication, triggers with pulses applied to the input...
This circuit was found in a Philips documentation from 1966. Its purpose is to drive the solenoid...