This circuit was found in a 1966’s American publication. What it does is to receive a pulse and keep it for intervals of up to 1 minute at the output.
This inverter bistable buffer circuit was obtained in a Hands On of the 90's. Next to the circuit we...
We find this circuit in a Popular Electronics of the 80's. The frequency range depends on C1 and...
Suggested by a Popular Electronics from the 90s, this circuit triggers an external load, relay or...