This circuit, found in a 1977 documentation, indicates when the grid voltage goes through zero. Under these conditions, it produces an output pulse whose duration depends on the capacitor.
This power control with SCR was found in Radio Electronics from April 1966. The components are...
A frequency divider for digital signals can be constructed based on a single 4018 integrated...
The circuit shown is from Motorola's 1990 Linear Databook. Shaded components are optional. The...