Television transmitter employing klystron with nonlinearity corr

Facsimile and static presentation processing – Facsimile – Specific signal processing circuitry

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

330 44, 455126, H04N 538

Patent

active

049050869

ABSTRACT:
A television transmitter includes a klystron power amplifier, a non-linearity pre-correction circuit in a stage preceding the klystron power amplifier, a non-linearity detection circuit for detecting the non-linearity of the output of the klystron power amplifier, a first level controlling circuit for controlling the level of the output of the non-linearity pre-correction circuit in response to the output of the non-linearity detection circuit, a hum frequency component detection circuit for detecting a hum frequency component of the output of the klystron power amplifier and a second level controlling circuit for controlling the level of either the input or the output of the non-linearity pre-correction circuit in response to the detected hum frequency component. The first and second level controlling level circuits are preferably variable attenuators. Preferably, the hum component detection circuit is an AGC circuit, which preferably detects the pedestal level in the output of the power amplifier, and then applies the detected level to a bandpass filter which passes a component of substantially 50 to 60 Hz contained in the pedestal level. A comparator compares the output of the bandpass filter against a reference level and generates an error signal, which is employed to control the second variable attenuator, which is either at the input or the output of the pre-correction circuit.

REFERENCES:
patent: 4485349 (1984-11-01), Siegel et al.
patent: 4670789 (1987-06-01), Plume
patent: 4701717 (1987-10-01), Radermacher et al.
patent: 4710815 (1987-12-01), Douglas et al.
patent: 4733192 (1988-03-01), Heppinstall et al.
J. B. Bullock, "A System for Reducing the Power Required by UHF-TV Transmitters", NAB Engrg. Conference, Mar. 21-24, 1973.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Television transmitter employing klystron with nonlinearity corr does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Television transmitter employing klystron with nonlinearity corr, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Television transmitter employing klystron with nonlinearity corr will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-177799

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.