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.
Found in a magazine 73 for radio amateurs, this circuit has two settings, one for the interval and the...
This good quality amplifier found in a 1982 documentation has a traditional complementary output...
A low frequency divider can be made using common unijunction transistors as shown by the figure...