05453796 is referenced by 109 patents and cites 8 patents.

A television receiver system having PIP capability includes two NTSC tuners and signal processing arrangements, and an HDTV tuner and signal processing arrangement. In order to accomplish a CHANNEL SWAP function, a controller searches a table for data indicative of pairing of NTSC channels and HDTV channels, the NTSC channel associated with the main channel HDTV source is tuned by the PIP NTSC tuner, and the HDTV channel associated with the PIP NTSC source is tuned by the HDTV tuner. If the inset image has no paired HDTV channel then the second NTSC tuner is controlled to select the channel formerly tuned by the PIP NTSC tuner.

Title
Signal swap apparatus for a television receiver having an HDTV main picture signal processor and an NTSC Pix-in-Pix signal processor
Application Number
8/266902
Publication Number
5453796
Application Date
June 28, 1994
Publication Date
September 26, 1995
Inventor
Robert D Altmanshofer
Carmel
IN, US
David J Duffield
Indianapolis
IN, US
Agent
Thomas F Lenihan
Peter M Emanuel
Joseph S Tripoli
Assignee
Thomson Consumer Electronics
IN, US
IPC
H04N 5/261
H04N 5/260
H04N 5/45
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