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 was obtained from an old American documentation, and practically any general-purpose transistor...
This transistorized circuit appeared in a Radio Electronics magazine in March 1958. The frequency range...
This old common analog telephone circuit was found in 1967 American documentation. The circuit uses...