PHONEUSE.GIF is a schematic drawing of a simple two transistor circuit that illuminates an LED when a phone line is in use. The circuit draws less than 7 microamps from the phone line and is powered by two 1.5 volt batteries. The device is used to warn against using a phone during data transfers on another extension. It provides only an indication, and will not prevent another extension from picking up the line. Requires 8 components in
addition to battery, as well as knowledge of electronics schematics and how to build electronics circuitry.
Note: The reviewer did not have the necessary parts or knowledge to build this circuit and test it for functionality. Proceed with this project at your own risk. Neither the Author nor America Online, Inc. is responsible for any damage caused by this circuit.