Phone Busy Indicators


Posted on Feb 5, 2014

It signals that the phone is in use by lighting a red LED. When the phone is not in use, a green LED is lit. It needs no external power and can be connected anywhere on the phone line, even mounted inside the phone. 4. The ring voltage on a phone line is anywhere from 90 to 130 volts. Make sure no one calls while you are making the line connections or you`ll know it.


Phone Busy Indicators
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