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Which type of echo is found mostly on tail circuits and is due to reflection that causes the Tx signal to appear on the Rx signal?
A. Hybrid echo
B. Talker echo
C. Listener echo
D. Tail-end echo
Correct Answer: A
Explanation/Reference:
Explanation:
Introduction
This document describes how to troubleshoot and eliminate echo where possible in IP Telephony networks with Cisco IOS® gateways.
There are two sources of echo:
* Hybrid echo
* Acoustic echo
Hybrid echo is caused by an impedance mismatch in the hybrid circuit, such as a two-wire to four-wire interface. This mismatch causes the Tx signal to appear on the Rx signal.
Acoustic echo is caused by poor acoustic isolation between the earpiece and the microphone in handsets and hands-free devices.