Found in old American documentation, this circuit is intended for the control of heating elements. The SCR must have current according to the controlled load. Transistors are from the time.
Decade counters, such as the 4017, can be cascaded as sourcing signals with the frequency divided...
This oscillator is a 1950s application of one of the first types of commercial transistors, the...
This circuit was found in a documentation by A. Fanzeres making use of a grounded metal housing...