Found in American documentation from the 90s, this circuit keeps the high beam on for a time determined by the trimpot adjustment. The relay is sensitive 12 V.
This circuit is from a 1979 publication. The sensor consists of plates or screens that, when...
The circuit is from a Radio Electronics from August 1989. The cells used at that time did not have...
The automatic modulated siren circuit shown in the figure really produces an interesting sound...