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.

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