This simple metronome, from 1985 documentation uses only transistors and has two settings. For voltages above 6 V, up to 12 V, replace the BC557 with a BD136.
An OR gate can be implemented with an LM3900 transconductance operational amplifier. The circuit is...
This traditional relay configuration, found in old documentation, is intended for 2A relays for...
This simple radio circuit was obtained in a Japanese publication in 1967. The circuit uses...