Browse Prior Art Database

Modem Equalization Using Multilevel Switch

IP.com Disclosure Number: IPCOM000079496D
Original Publication Date: 1973-Jul-01
Included in the Prior Art Database: 2005-Feb-26
Document File: 2 page(s) / 34K

Publishing Venue

IBM

Related People

Moisey, D: AUTHOR

Abstract

Equalization of modems is usually done by trained personnel using a portable meter and adjusting a number of equalizers.

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Modem Equalization Using Multilevel Switch

Equalization of modems is usually done by trained personnel using a portable meter and adjusting a number of equalizers.

In the present arrangement, a meter is permanently installed in the modem and connected to a signal sample point. Five equalizers (three midband, one lowband, and one highband) are connected to selected positions on respective levels of a five-level, 16-position rotary switch (see sketch). Rotation of the switch through its 16 positions causes different combinations of the five equalizers to be enabled. One of these 16 sequential discrete positions corresponds to an adequate degree of equalization for the modem.

This arrangement permits an untrained customer to achieve equalization of a modem on customer premises by rotating the switch to the one of 16 positions, for which the meter indicates best equalization.

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