Facsimile and static presentation processing – Facsimile – Specific signal processing circuitry
Patent
1977-09-16
1978-10-24
Martin, John C.
Facsimile and static presentation processing
Facsimile
Specific signal processing circuitry
325422, 334 16, 325459, H04N 550, H04B 116
Patent
active
041224930
ABSTRACT:
Circuitry compensating for inherent nonlinearities in the tuning voltage sensitivity of varactor tuners, thereby providing relatively constant AFC pull-in range throughout the band of operating frequencies, is shown. In both the VHF and UHF bands, the AFC system develops an error correction voltage in proportion to the tuning voltage. With respect to reception of VHF channels, a gain switching circuit operates to reduce the proportion of AFC error correction voltage developed on a High Band VHF channel, thereby compensating for increased tuning voltage sensitivity on High Band VHF. With respect to reception of UHF channels, a tuning voltage sensing circuit operates to effect an error correction voltage that is a greater proportion of the tuning voltage when the tuning voltage is above a pre-determined value corresponding to approximately channel 60.
REFERENCES:
patent: 3825858 (1974-07-01), Amemiya et al.
patent: 3959728 (1976-05-01), Yamazaki et al.
patent: 4005256 (1977-01-01), Arumugham
Arumugham Rangaswamy
Kam George Hager
GTE Sylvania Incorporated
Martin John C.
Odozynski John A.
LandOfFree
Adaptive wideband AFC system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Adaptive wideband AFC system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Adaptive wideband AFC system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2339620