Ultra-simple Voltage Probe
Sunday, August 9th, 2009
Detects 1.8 to 230 Volts DC or AC. This circuit is not a novelty, but it proved so useful, simple and cheap that it is worth building. When the positive (Red) probe is connected to a DC positive voltage and the Black probe to the negative, the Red LED will illuminate. Reversing polarities the Green [...]
