This windshield wiper timer was obtained in an 80's Hands On. The transistor can be the BC548 and the relay is 12 V sensitive. The time is set to R3.
This circuit is from an 80's documentation. The BC108 can be replaced by the BC548 and the 2N3055...
This circuit was found in a 73 amateur radio magazine from the 90s. An LED extends the scale from 0...
The diodes are for general use and the transistors also in this Exclusive-OR circuit. The circuit may...