George D Kam, 751173 Starwood Pass, Barrington Hills, IL 60102

4153914, May 8, 1979

Mar 31, 1978

5/892118

Rangaswamy Arumugham - Batavia NY
George H. Kam - Tonawanda NY

GTE Sylvania Incorporated - Stamford CT

H04N 550
H04B 116
H03K 500

358195

A network for combining a switchable and variable tuning voltage with an AFC voltage so as to effect a change in the tuning control voltage at a tuner's tuning control terminal is disclosed. The network compensates for time delays associated with the AFC time-constant in a manner such that the tuning control voltage responds in proportion to and substantially instantaneously with changes in the tuning voltage. The compensation reduces the probability of AFC false-locking phenomena when, for example, switching from one channel of a television receiver to another.

4019160, Apr 19, 1977

Dec 5, 1975

5/638144

George H. Kam - Tonawanda NY

GTE Sylvania Incorporated - Stamford CT

H03H 724
H03G 300
H04N 552

333 81R

In a tuner for a television receiver, an attenuator circuit coupling a signal input to a signal output network includes a series connected controllable impedance and amplifier stage connected to a source of AGC potential whereby increased signal strength causes an increased AGC potential which reduces current flow through and increases the impedance of the controllable impedance while reducing the gain, and consequently the noise, of the amplifier stage coupled to the signal output network. In another aspect of the invention, a second attenuator circuit includes a second controllable impedance series coupling a signal input to the attenuator circuit and a third controllable impedance coupling the junction of the first and second controllable impedances to circuit ground for effecting an additional increased attenuation of a received signal.

4122493, Oct 24, 1978

Sep 16, 1977

5/833759

Rangaswamy Arumugham - Batavia NY
George Hager Kam - Tonawanda NY

GTE Sylvania Incorporated - Stamford CT

H04N 550
H04B 116

358195

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.

4218720, Aug 19, 1980

Feb 22, 1979

6/013851

George H. Kam - Tonawanda NY
John D. Lovely - Batavia NY

GTE Products Corporation - Stamford CT

H02H 308

361 93

A protection circuit for television receiver picture tubes and related components which includes a diode which is forward biased during normal operation to provide coupling of the tube control grid to ground or reference potential and which is reverse biased during operation at excessively large beam currents, the reverse biasing of the diode causing the beam current to flow through a large grid-cathode resistor thereby effectively limiting electron beam current.

4130829, Dec 19, 1978

Jan 23, 1978

5/871321

George H. Kam - Tonawanda NY
Robert P. Logan - Framingham MA

GTE Sylvania Incorporated - Stamford CT

H04N 962
H04N 920

358 10

Cathode ray tube adjusting apparatus in a color television receiver includes a matrix and amplifier circuit coupled to a chrominance signal source, selectively coupled by a "service-normal" switch to a luminance or reference signal source. The matrixing and amplifying circuit includes a control grid DC bias potential development circuit and a cathode DC bias potential adjusting circuit, and is coupled to a cathode ray tube. In the "service" switching position, the DC bias potential adjusting circuit is varied to provide the proper cut-off potential conditions for the cathode ray tube. In the "normal" switchingposition, chrominance and luminance signals are matrixed and luminance signal drive is adjusted to provide the proper color temperature appearing on a viewing screen of the cathode ray tube.

4245186, Jan 13, 1981

Dec 11, 1978

5/968068

Rangaswamy Arumugham - Acton MA
George H. Kam - Tonawanda NY

GTE Products Corporation - Stamford CT

G05F 320

323225

A high input impedance, low output impedance, temperature-stable tuning voltage interface circuit with substantial ripple rejection and negligible DC offset. The circuit comprises two transistors of opposite conductivity types, the first being coupled through a resistor to a supply voltage and through a temperature-stabilizing, DC-offsetting diode to the output of the second transistor. The rejection of the ripple voltage superimposed on the supply voltage is determined by the ratio of the value of the resistor to the effective resistance of the diode.