Patent ID: 6798866
Filing Date: 2004-09-28
Classification: H04M

Abstract:
A transmitter for verifying connectivity of a shared telephone line comprising:a high frequency oscillator for generating a carrier signal; a low frequency oscillator for generating an audible signal; an amplitude modulator in communication with each of the high frequency oscillator and the low frequency oscillator, wherein the amplitude modulator mixes the carrier signal and the audible signal to produce an amplitude-modulated test signal; a gate in communication with the low frequency oscillator and the amplitude modulator, wherein the gate regulates the flow of the audible signal from the low frequency oscillator to the amplitude modulator; a high-pass filter in communication with the amplitude modulator, wherein the high-pass filter receives the amplitude-modulated test signal and removes any residual low frequency signal output by the amplitude modulator; and a connector in communication with the high-pass filter, wherein the connector is adapted to send the amplitude-modulated test signal to a central office side of the telephone line.