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.
This circuit was found in the November 1966 issue of Electronics Now magazine. It uses an LDR as a...
Found in a National Semiconductor manual from the 1980s, this circuit uses a voltage comparator of the...
This 80's circuit uses germanium transistors like the AC125, AC151, AC163, 2N506 and others to...