This crystal configuration can be made with triggers of any logic. The frequency is given by the formula next to the diagram. This setting is specifically for TTL.
This circuit trips when a negative pulse is applied to its input or when the voltage drops below a...
This is an old 1988 circuit consisting of a timer or time control for exposing silk-screen arrays. The...
This circuit was taken from an old American documentation. It can be built with modern op amps. The...