With this system you can disconnect phone lines in case of need for protection. The circuit is from a 1989 documentation working only with analog lines.
This simple MW radio does not need an external antenna to pick up local stations. It was found in a...
This is a typical ohmmeter circuit with 50 uA analog instrument. The circuit was found in Radio...
This very simple circuit turns on an LED when an object interrupts the light that falls on the...