Television – Special applications – Manufacturing
Patent
1993-07-27
1995-04-04
Groody, James J.
Television
Special applications
Manufacturing
4552262, 4551841, H04N 550
Patent
active
054041619
ABSTRACT:
Disclosed is a tuned channel detector which includes a cable path between a radio frequency source and a receiver such as a TV, wherein the radio frequency source passes first through an attenuator and second through a signal selection module comprising two opposing directional couplers and a single-pole/double-throw switch. The channel to which the TV is tuned is determined by measuring the TV's local oscillator signal from the cable which feeds the radio frequency signal to the TV and, additionally or alternatively, by comparing the signal strength of the input and reflected TV carrier signals at and around the channels under test. Signal detection is further enhanced by modulating the signal mixed with the local oscillator with a tone and/or testing only during certain intervals such as the vertical synchronization interval or the power line cycle. A tone detector having a synchronous rectifier is used to detect low level local oscillator signals. Tuned channel detection is further enhanced through the use of artificial intelligence techniques.
REFERENCES:
patent: 3312900 (1967-04-01), Jaffe
patent: 3639686 (1972-02-01), Walker et al.
patent: 3864636 (1975-02-01), Fukuda et al.
patent: 4020419 (1977-04-01), Caspari et al.
patent: 4044376 (1977-08-01), Porter
patent: 4058829 (1977-11-01), Thompson
patent: 4216497 (1980-08-01), Ishman et al.
patent: 4270212 (1981-05-01), Furukawa
patent: 4331973 (1982-05-01), Eskin et al.
patent: 4331974 (1982-05-01), Cogswell et al.
patent: 4425578 (1984-01-01), Haselwood et al.
patent: 4509203 (1985-04-01), Yamada
patent: 4561112 (1985-12-01), Ridder
patent: 4577220 (1986-03-01), Laxton et al.
patent: 4622583 (1986-11-01), Watanabe et al.
patent: 4630108 (1986-12-01), Gomersall
patent: 4633315 (1986-12-01), Kasperkovitz
patent: 4723302 (1988-02-01), Fulmer et al.
patent: 4736390 (1988-04-01), Ward et al.
patent: 4764808 (1988-08-01), Solar
patent: 4783843 (1988-11-01), Leff et al.
patent: 4789897 (1988-12-01), Kappeler et al.
patent: 4847685 (1989-07-01), Gall et al.
patent: 4876736 (1989-10-01), Kiewit
patent: 4878245 (1989-10-01), Bradley et al.
patent: 4885632 (1989-12-01), Mabey et al.
patent: 4929905 (1990-05-01), Ruitenburg
patent: 5193216 (1993-03-01), Davis
Douglass Ralph G.
Furman Arthur R.
Groody James J.
Information Resources, Inc.
Murrell Jeffrey S.
LandOfFree
Tuned signal detector for use with a radio frequency receiver does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Tuned signal detector for use with a radio frequency receiver, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Tuned signal detector for use with a radio frequency receiver will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2382854