We found this circuit in a 1996 publication. The circuit uses components that are still common. The timing depends on C1, which can be changed, and the triac can be of any type.
The integrated circuit of this 1976 configuration is the 7400 and the type crystal in televisions of the...
We found this divider in a circuit manual from the 90s. The circuit is intended for operation with...
Recommended for automotive applications, this circuit was found in an April 1982 Radio Electronics...