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 solid-state relay (SSR) or shield was found in a 1995 Electronics Now. The transistor can be...
The output current of this circuit reaches 12 mA. The zener diode determines the output voltage. The...
In the figure we have an IF amplifier step using a MOSFET. The circuit was found in a 1980s...