Manual

DH 1 and ECA 1 Installation

ECA 1

DH 1

The DH 1 Digital Hybrid allows audio conferencing

over a standard POTS 2-wire phone line. A 32 millisecond

Line Echo Canceller is utilized to remove line echo caused

by the four-wire to two-wire conversion. In a standard

telephone the echo caused by this conversion is actually

beneficial to the user as side-tone. With a conference system

line echo can cause all types of problems including feed-

back and echo canceller problems.

11580

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H 1H 1

H 1

DIGITAL HYBRID

The DH 1 installs by first temporarily removing the top

cover of the ECM 64 and the rear phone jack cover on the

back of the ECM 64. See the diagram on page Manual-6.

Seat the DH 1 module from its bottom side onto the ECM

64 J10 header. Make certain that the header pins are

properly aligned with the DH 1 before applying force to seat

the card.

Warning: To protect against damage from electrostatic

discharge (ESD) proper ESD control measures must be

followed when installing the DH 1.

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I N ST ALLA TI O N MAN UAL STALLA ALLATI TIO MANU DH 1 DIGITAL HYBRID The DH 1 Digital Hybrid allows audio conferencing over a standard POTS 2-wire phone line. A 32 millisecond Line Echo Canceller is utilized to remove line echo caused by the four-wire to two-wire conversion. In a standard telephone the echo caused by this conversion is actually beneficial to the user as side-tone. With a conference system line echo can cause all types of problems including feedback and echo canceller problems.