3578914 is referenced by 38 patents.

Automatic line build-out is provided in the equalizer stage of a PCM telephone repeater to correctly and continuously match the repeater automatically to any line length and to varying line parameters. To reduce the power requirements to a minimum, the circuit utilizes the equalized signal itself to determine the amount of degradation and to derive therefrom a control voltage which controls, without power consumption, the amount of series resistance inserted by the line build-out network between the cable and the equalizing circuit. The control is achieved by means of a field-effect transistor passively connected as a variable resistance.

Equalizer with automatic line build-out
Application Number
Publication Number
Application Date
April 9, 1969
Publication Date
May 18, 1971
Simonelli Richard A
Lynch Communication Systems
H04b 03/14
H04B 03/14
H04B 03/04
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