This simple circuit makes use of neon lamps to indicate the voltage of a power grid. The lamps are common neon and the circuit indicates whether the voltage is 110 V or 220 V.
We found this circuit in the November 1994 issue of Electronics Now magazine. It doubles the...
This filter is inserted between the interfering device and the interfering device. The coils are...
The keyboard for this organ is made by small metal plates where the probe touches when in...