3707683 is referenced by 5 patents and cites 4 patents.

A circuit for producing a timing signal from a modified duobinary data signal. This data signal is capacitively coupled through four full-wave rectifiers that are connected in series. The outputs of the third and fourth rectifiers are DC coupled through an adder to a bandpass filter which passes a timing signal that has a fixed phase relationship with respect to the timing signal that was originally employed to produce the modified duobinary signal. The filtered signal is delayed, squared in a limiter, and applied to a zero crossing detector which produces a train of clock timing pulses.

Title
Timing recovery circuit for use in modified duobinary transmission system
Application Number
05/198,883
Publication Number
3707683
Application Date
November 15, 1971
Publication Date
December 26, 1972
Inventor
Dotter Jr Berton E
Assignee
GTE Automatic Electric Laboratories Incorporated
IPC
H03b 01/00
H04L 07/02
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