04335402 is referenced by 96 patents and cites 1 patents.

A teletext system transmits auxiliary information before the vertical sync pulse in the vertical blanking interval to avoid interference to the normal transmitted picture. At the transmitter a time gap is placed in the auxiliary information to allow for the equalizing pulses, while at the receiver the gap is removed. One, two, or all three lines that occur before the vertical sync pulse in the vertical blanking interval can be used to transmit the auxiliary teletext information signals.

Title
Information transmission during first-equalizing pulse interval in television
Application Number
6/206946
Publication Number
4335402
Application Date
November 14, 1980
Publication Date
June 15, 1982
Inventor
David D Holmes
Trenton
NJ, US
Agent
Henry I Steckler
William H Meise
Paul J Rasmussen
Assignee
RCA Corporation
NY, US
IPC
H04N 7/08
View Original Source