Power Outlet Tester using Bicolor LEDs

摘要

This handy tester can do more. It uses just four resistors (two times two resistors in series to halve the voltage stress on each resistor), two bi-color LEDs and a pushbutton. The complete circuit can be fitted inside a standard 3-pin plug-top with an Earth connector. Make sure that the circuit is completely enclosed in the plug housing and that the pushbutton is rated at AC line voltage.