Television tuner for receiving multiple band television signals

• US 5,010,400 A
• Filed: 08/02/1989
• Issued: 04/23/1991
• Est. Priority Date: 08/03/1988
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Oto, Hideki
• Primary Examiner(s): Britton, Howard W.
• Assistant Examiner(s): Lee, Michael H.
• Application Number:
  US07/388,493
• Time in Patent Office: 629 Days
• Field of Search: 358/191.1, 358/193.1, 358/86, 455/188, 455/189, 455/190, 455/191, 455/131, 455/137, 455/168, 455/176, 455/179, 455/180, 455/315
• US Class Current: 725/68
• CPC Class Codes: H03J 5/242 used exclusively for band selection
• CPC Class Codes: H04N 7/10 Adaptations for transmission by electrical cable H04N7/12 takes precedence
• CPC Class Codes: H04N 7/20 Adaptations for transmission via a GHz frequency band, e.g. via satellite

Abstract

A television tuner for use in a television receiver to receive a VHF band signal, a UHF band signal, and a satellite band signal converted from a received satellite signal, all of which are provided as a combined signal by a signal combiner. The television tuner includes an input terminal to receive the combined signal from the signal combiner, a first oscillator having a variable frequency, a first mixer to receive the combined signal and the output of the first oscillator to convert the combined signal into a first intermediate frequency signal if the VHF and UHF signals are to be utilized by the television receiver, or a second intermediate frequency signal if the satellite signal is to be utilized by the television receiver, first and second band-pass filters connected to the first mixer to receive first and second intermediate frequency signals, wherein the first band-pass filter is designed to pass the first intermediate frequency signal and the second band-pass filter is designed to pass the second intermediate frequency signal, and a processing circuit for processing the signals passed by the first and second band-pass filters to provide a standard VHF and UHF television signals and a frequency modulated satellite signal.

Claims

1. A television tuner for use in a television receiver to receive a VHF signal band, a UHF signal band, and a satellite signal band converted from a received satellite signal, all of which are provided as a combined signal by a

an input means to receive the combined signal from the signal combiner;

first oscillator having variable frequency;

first mixer means to receive the combined signal and the output of the first oscillator means to convert the combined signal into a first intermediate frequency signal if the VHF and UHF signals are to be utilized by the television receiver or a second intermediate frequency signal if the satellite signal is to be utilized by the television receiver;

first and second band-pass filter means connected to the first mixer means to receive first and second intermediate frequency signals, wherein the first band-pass filter means is designed to pass the first intermediate frequency signal and the second band-pass filter means is designed to pass the second intermediate frequency signal; and

means for processing the signals passed by the first and second band-pass filter means to provide a standard VHF and UHF television signals and a frequency modulated satellite signal.

2. A television tuner as in claim 1, wherein the means for processing the signals includes:

a second oscillator means having a fixed frequency;

a second mixer means for receiving the output of the second oscillator means and the output of the first bandpass filter means to generate a signal having a third intermediate frequency;

a third band-pass filter means for receiving the third intermediate frequency signal; and

a first amplifier means connected to the output of the third band-pass filter means for outputting the standard television IF frequency of the VHF and UHF television signals.

3. A television tuner as in claim 1, wherein the means for processing the signals includes:

a second amplifier means connected to the output of the second band-pass filter means for outputting the frequency modulated satellite signal.

4. A television tuner as in claim 1, wherein the input means includes filter means for selectively transmitting at least one of the VHF, UHF and satellite band signals received as part of the combined signal.

5. A television tuner as in claim 4, wherein the filter means includes a low-pass filter and a high-pass filter, each having variable cut-off frequencies.

6. A television tuner as in claim 4, wherein the filter means includes at least two band-pass filters, each having fixed frequency ranges, and a switching means for selectively switching the combined signal between the at least two band-pass filters.

7. A television tuner for use in a television receiver to receive multiple band television signals, all of which are provided as a combined signal by a signal combiner, comprising:

an input means to receive the combined signal from the signal combiner;

first oscillator means having a variable frequency;

first mixer means to receive the combined signal and the output of the first oscillator means to convert the combined signal into a first intermediate frequency signal if a prescribed one of the band television signals to be utilized by the television receiver or a second intermediate frequency signal if another one of the band television signals is to be utilized by the television receiver;

first and second band-pass filter means connected to the first mixer means to receive first and second intermediate frequency signals, wherein the first band-pass filter means is designed to pass the first intermediate frequency signal and the second band-pass filter means is designed to pass the second intermediate frequency signal; and

means for processing the signals passed by the first and second band-pass filter means to provide standard television signals.