Various diagram

When the Set switch is depressed the large electrolytic capacitor is charged via the limiting resistor (lk). This charge causes the BC109 to conduct which supplies enough base current to switch on the 2N1711 space and operate the relay.
The relay contacts are wired in parallel with the mains switch so that if the mains switch is now turned off, the equipment will continue.The supply·voltage is taken from the equipment in which the unit is fitted and will determine the choice of` relay. The maximum delay being 1.75 hours.


Snooze Delay Timer Circuit