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.
This circuit fires at the touch of a sensor, passing its output from high to low in a time given by...
This circuit was found in a 1967 US publication. In it we have the implementation of a ring...
The strength of an audio signal can be controlled by touching sensors. Keeping the finger in...