Television receiver
October 18, 2017. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3454710 TVRO receiver system with low-cost video-noise reduction filter Up-conversion homodyne receiver for cable television converter with frequency offset to avoid adjacent channel interference Bandwidth limiting circuit with variable bandwidth Interference filter with high degree of selectivity for TVRO receiver system Dual port oscillator for two-stage direct conversion receiver Method and apparatus for recovering baseband signals from in-phase and quadrature-phase signal components having phase error therebetween Composite signal detecting apparatus having associated filter Television signal receiver Video signal detection circuit and video signal processing device Patent #: 5864373 InventorsAssigneeApplicationNo. 952077 filed on 10/18/1997US Classes:348/725, RECEIVER CIRCUITRY348/607, Noise or undesired signal reduction348/735, Automatic frequency control348/737, Intercarrier circuits455/260, Phase lock loop or frequency synthesizer455/264, Voltage control of oscillator455/266, Selectivity or bandwidth control455/307With specific filter structureExaminersPrimary: Eisenzopf, Reinhard J.Assistant: Natnael, Paulos M. Attorney, Agent or FirmInternational ClassesH04N 005/44H04N 005/21 H04N 005/50 H04N 005/62 H04B 001/06 Foreign Application Priority Data1996-04-04 JPAbstractIn a television receiver having a tuner 2 for converting a received signal from an antenna 1 to an intermediate frequency signal and supplying the intermediate frequency signal to a homodyne detector circuit through a filter device to extract a video signal, a variable frequency oscillator is provided for changing the frequency of the intermediate frequency signal such that the frequency of beat components between a local oscillating signal of the tuner and a harmonic signal of the intermediate frequency signal is coincident with a trap frequency of the filter device. The occurrence of interference due to the intermediate frequency signal introducing into the antenna can be prevented by a simple configuration.Field of SearchAutomatic frequency controlIntercarrier circuits Noise or undesired signal reduction Tuning Phase lock loop or frequency synthesizer Utilizing particular local oscillator control With specific filter structure Voltage control of oscillator Image frequency suppression Undesired signal or noise control (e.g., antistatic) With image frequency suppression Unwanted oscillation or radiation prevention Internally generated noise or oscillations Homodyne (i.e., zero beat or synchrodyne reception) Including distributed electrical parameter structure With balanced mixer Stripline Hollow waveguide Electron beam tube With nonlinear impedance (e.g., diode) Variably tunable or adjustable Selectivity or bandwidth control | |
