This sensitive circuit for triggering relays was found in an old English publication. It works with alternating signals applied to its input. Transistors are general purpose types.
We found this circuit in a Popular Electronics of the 90s. The MOSFET can be of any type,...
In fact, the correct name would be a hearing aid amplifier. However, we use the name of the...
This circuit controls a relay causing it to open and close its contacts at a speed that depends on the...