Found in American documentation from 1969, this circuit operates in the frequency range 10 to 150 Hz providing signals as shown in the diagram itself.
This metal detector was found in a 2001 Poptronics, but it can still be easily assembled, as the...
This circuit for 6 lamps was found in old American documentation. The supply is of high voltage...
With this circuit it is possible to have a safe indication of the balance point for the signals of the...