Method and apparatus for testing the tip-ring polarity of telephone receptacles connected in parallel to a non-working pair

摘要

A method and apparatus for testing the tip-ring polarity of telephone receptacles connected in parallel to a non-working pair includes a battery and an LED, the device being capable of being plugged into a subscriber's telephone receptacle. When a diode is properly placed across the non-working pair, the LED will light if the final terminals of the receptacle are wired with the correct tip-ring polarity. The disclosure teaches that the diode may be incorporated in various types of packages and may be connected across the non-working pair in several different ways.