Hello,

I have a world war two air raid siren that requires 120/220 VAC. I have been trying to find a simple schematic for a 2-12 VDC curcuit that will allow me to adjust the time that the contacts would be closed and open in a simple relay. Can anyone offer some ideas?

Or does anyone know where I could find a relay with a such a feature built in?

Thanks,
stornborg

 

A simple 555 can set both on and off durations, just let us know how long.