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.
March 2017 - The new ERB-RD, ERB-RE and ERB-RG fuses from Panasonic's Micro Chip Fuses can now be...
Constant currents from 10 mA to 1 A can supply the load, depending on the selection made by S1. Q1...
The optocoupler in the figure uses common transistors and a phototransistor to drive a sensitive relay...