Title: Variable ramp speed TV tuning system for rapid channel tuning

Abstract: Disclosed is a microcomputer-controlled frequency synthesis television tuning system utilizing variable tuning ramp speeds following channel selection. Channel tuning is expedited by means of three ramping speeds employed during the tuning process. The system initially ramps quickly toward the selected channel and then automatically and incrementally reduces tuning speed as the proper frequency is approached. Once the proper frequency has been reached, the variable ramp speed signal acquisition mode is terminated and an AFC mode is initiated. Large frequency changes are thus made possible over short periods to accomodate widely separated channels efficiently.

Do you think this is a good invention? Vote now:

Votes so far: For:(0) Against:(0)
Other info:

Inventors: Citta, Richard W. (Portland, OR)
Falater, Scott L. (Melbourne, FL)

Application Number: 06/220619
Filing Date: 1980-12-29
Publication_date: 1983-02-15
Assignee: ZENITH RADIO CORP

Primary Class(es): 455/164.200 455/182.200, 455/186.100, 348/735, 455/184.10
Other Classes: H03J1/00; H03J7/26; H03J7/18; H04N5/50; H03J7/06; H04B1/16
US Patent Ref:

3943449	March, 1976	Hendrickson et al.	455/186	Multi-speed ramp for a varactor tuning system
4070629	January, 1978	Merrell	High speed tuning system
4105948	August, 1978	Wolkstein	Frequency synthesizer with rapidly changeable frequency
4114100	September, 1978	Klank	Rapid tuning circuit for high frequency receivers
4156197	May, 1979	Merrell	High speed phase locked loop tuning system
4254506	March, 1981	Henderson et al.	455/186	Channel identification apparatus useful in a multiband sweep type tuning system
4291413	September, 1981	Henderson et al.	455/185	Search type tuning system with direct address channel selection apparatus

Other Refs:
Primary Examiner: Ng, Jin F.
Assistant Examiner:
Attorney: Murray, James E.

Claims:

We claim:<