Suggested by General Electric documentation from 1968, this circuit activates a relay after 60 seconds, keeping it closed. PUT is an uncommon component today.
We found this circuit in April 1979 Radio Electronics magazine. The circuit is based on the 555...
This circuit was found in a Popular Electronics from the 90s. The circuit uses general purpose...
This 80's circuit uses an integrated amplifier of the era, but nothing prevents it from being...