PURPOSE: To demonstrate that what comes out of a 110 VAC plug is in fact alternating current.
DESCRIPTION: The bi-color LED is wired across the 110 VAC line. When current flows one direction the red side glows, and when current flows the other direction the green side glows, so if it is viewed from a distance the color appears yellow. When the device is swung in a circle the alternating colors become easily visible, indicating that the current in the line is alternating direction.
REFERENCES: (PIRA unknown.)
EQUIPMENT: Red/green bi-color LED wired to 6-volt line transformer.
SETUP TIME: None.
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