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.
We found this circuit in a Poptronics from 1998. The circuit can be extended to more competitors...
This basic circuit can be used in signal followers and other applications where an RF signal is to be...
This circuit trips when the input voltage exceeds 30 V. Its base is a DIAC and it can be used to...