Specified Stage (e.g., Mixer, Amplifier, Or Demodulator) Patents (Class 455/293)
  • Patent number: 4426737
    Abstract: A receiver is provided with a surface elastic wave amplifier of a parametric amplification type within an HF amplifier unit, and with a circuit for providing pumping power for said surface elastic wave amplifier from oscillating outputs of an IF converting local oscillator of the receiver.
    Type: Grant
    Filed: February 3, 1982
    Date of Patent: January 17, 1984
    Assignee: Clarion Co., Ltd.
    Inventor: Masaharu Mori
  • Patent number: 4414688
    Abstract: RF-input stage for TV receivers comprising a field effect transistor in grounded source circuit configuration and a frequency-dependent coupling network arranged between the gate electrode of the field effect transistor and an aerial input for selecting TV signals and transforming the signal impedance. The frequency-dependent coupling network is terminated with a resistor which is arranged between the gate electrode of the field effect transistor and ground and whose value has been chosen so that on the one hand this resistor terminates in conjunction with the input impedance of the field effect transistor the frequency-dependent coupling network with an acceptable reflection factor and on the other hand forms in conjunction with the output impedance of the frequency-dependent coupling network an impedance at which the noise contribution of the field effect transistor is at least substantially at its lowest.
    Type: Grant
    Filed: October 7, 1981
    Date of Patent: November 8, 1983
    Assignee: U.S. Philips Corporation
    Inventors: Johannes H. Hendriks, Johannes J. M. Van Daal
  • Patent number: 4397037
    Abstract: A diplexer comprises a first frequency selective filter coupled between its first input terminal and a circuit point, a second frequency selective filter coupled between the circuit point and its output terminal, and third frequency selective filter coupled between its second input terminal and the circuit point. The first filter selects frequencies higher than a first frequency and the second filter selects frequencies lower than a second frequency which is higher than the first frequency. The third filter selects frequencies lower than a third frequency which is lower than the first frequency. In a television receiver, the first and second filters serve as a bandpass filter for the UHF band, and the third filter passes the VHF and CATV bands.
    Type: Grant
    Filed: August 19, 1981
    Date of Patent: August 2, 1983
    Assignee: RCA Corporation
    Inventor: Gerald E. Theriault
  • Patent number: 4287603
    Abstract: A radiated input mixer for converting a radio frequency (RF) signal into an intermediate frequency (IF) signal with the aid of a local oscillator (LO) signal includes, in combination, an antenna having balanced feed terminals, a diode quad, and a balun with balanced terminals orthogonally positioned with respect to the antenna terminals to provide a less complex and more efficient device of the type described than has heretofore been known in the art.
    Type: Grant
    Filed: August 23, 1979
    Date of Patent: September 1, 1981
    Assignee: The Bendix Corporation
    Inventor: Kenneth R. Moser