General Electric suggests this circuit in an 80's documentation. The circuit makes use of PUTs that are not common components today. Note the timing components that may change.
This circuit can be used in a differential metal detector to receive the signal from a...
This circuit uses a sensitive reed relay to control external loads. The time delay is given by the...
This amplifier, with a power that reaches 3 W, according to the power that can be from 9 to 14 V,...