Found in an old Popular Electronics, this circuit warns when a remote lighting system is not working. The circuit uses an LDR as a sensor and the components used are quite common today.
This circuit was found in an English magazine from 1979. The magazine no longer exists, but the...
This traditional TTL anti-clock setting was found in a 1993 American documentation. The circuit...
The astable multivibrator shown by the figure can produce signals in the 10 to 10 000 Hz band...