The purpose of this circuit is to improve a trigger circuit using a zener diode. The circuit was found in an American documentation from 1964. It can be improved using equivalent modern components.
We found this simple alarm circuit in a 1986 documentation. The circuit uses sensors of the NA...
This sound relay or Vox was found in 70s RCA documentation. SCRs can be common types today and...
Placed near a common receiver, this oscillator is intended to generate a beating signal to receive...