EP0317360A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Tuner for receiving television signal in frequency division multiplex system and television signal in time division multiplex system
Assignee: Sharp Corp
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Filing: 1988-11-21
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Granted: —
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Expires: 2008-11-21
Abstract
Abstract A tuner for use in two systems comprises a determining circuit (10). The determining circuit (10) determines whether or not a baseband signal as FM-demodulated includes a sound carrier, thereby to determine whether a received television signal is a television signal in the NTSC system or a television signal in the MUSE system. When the received television signal is a television signal in the NTSC system, switches (20, 30) are switched such that the baseband signal is applied to a signal processing circuit (40) for video and a signal processing circuit (50) for sound which are used in the NTSC system, and an averaging AFC (21) is selected. On the other hand, when the received television is a television signal in the MUSE system, the switches (20, 30) are switched such that the basehand signal is applied to an MUSE decoder (70), and a keyed AFC is selected.
Inventors
- 👤 Ken Satoh
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 02:33
CPC Classifications
H; H03; H03J; H03J7/00; H03J7/02; H03J7/04; H04; H04N; H04N5/00; H04N5/44; H04N5/46
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
176 words
A tuner for receiving a first television signal in which a sound signal is multiplexed on a video signal in a frequency-divisional manner using a carrier and a second television signal in which a sound signal and a video-signal are multiplexed in a time-divisional manner, comprising: first signal processing means (40, 50) for signal-processing the first television signal, to detect the sound signal and the video signal included therein, second signal processing means (70) for signal-processing the second television signal, to detect the sound signal and the video signal included therein, determining means (10) for determining whether or not the received television signal includes said carrier, and first switching means (30) for applying said received television signal to said first signal processing (40, 50) means in response to the determination by said determining means (10) that the received television signal includes said carrier while applying said received television signal to said second signal processing means (70) in response to the determination by said determining means (10) that said received television signal does not include said carrier.
Claim 2
Dependent Claim
176 words
A tuner for receiving a first television signal in which a sound signal is multiplexed on a video signal in a frequency-divisional manner using a carrier and a second television signal in which a sound signal and a video-signal are multiplexed in a time-divisional manner, comprising: first signal processing means (40, 50) for signal-processing the first television signal, to detect the sound signal and the video signal included therein, second signal processing means (70) for signal-processing the second television signal, to detect the sound signal and the video signal included therein, determining means (10) for determining whether or not the received television signal includes said carrier, and first switching means (30) for applying said received television signal to said first signal processing (40, 50) means in response to the determination by said determining means (10) that the received television signal includes said carrier while applying said received television signal to said second signal processing means (70) in response to the determination by said determining means (10) that said received television signal does not include said carrier.
Claim 3
Dependent Claim
118 words
The tuner according to claim 1, which further comprises first automatic frequency adjusting means (21) for keeping constant the frequency of said first television signal, and second automatic frequency adjusting (22) means for keeping constant the frequency of said second television signal, said first automatic frequency adjusting means (21) carrying out corresponding frequency adjustment with respect to said received television signal in response to the determination by said determining means (10) that said received television signal includes said carrier, said second automatic frequency adjusting means (22) carrying out corresponding frequency adjustment with respect to said received television signal in response to the determination by said determining means (10) that said received television signal does not include said carrier.
Claim 4
Dependent Claim
57 words
The tuner according to claim 1, wherein said determining means comprises out-of-synchronization detecting means (14) receiving said received television signal and a predetermined synchronizing signal for detecting the fact that said received television signal is not synchronized with said predetermined synchronizing signal, thereby to detect the fact that said received television signal does not include said carrier.
Claim 5
Dependent Claim
54 words
The tuner according to claim 1, wherein said determining means comprises out-of-synchronization detecting means (14) receiving said received television signal and a predetermined synchronizing signal for detecting the fact that said received television signal is synchronized with said predetermined synchronizing signal, thereby to detect the fact that said received television signal includes said carrier.
Claim 6
Dependent Claim
64 words
The tuner according to claim 1, which further comprises converting means (3) for making channel selection for said received television signal and converting the channel-selected television signal into a predetermined intermediate frequency signal, and FM demodulating means (4) for FM-demodulating said intermediate frequency signal to a baseband signal, to apply to the same to said determining means (10) and said first switching means (30).
Claim 7
Dependent Claim
163 words
The tuner according to claim 2, which further comprises converting means (3) for making channel selection for said received television signal and converting the channel-selected television signal into a predetermined intermediate frequency signal, and FM demodulating means (4) for FM-demodulating said intermediate frequency signal to a baseband signal, to apply the same to said determining means (10) and said first switching means (30), said first automatic frequency adjusting means (21) adjusting the frequency of said received television signal in said converting means (3) based on the baseband signal from said FM demodulating means (4) in response to the determination by said determining means (10) that said received television signal includes said carrier, said second automatic frequency adjusting means (22) adjusting the frequency of said received television signal in said converting means (3) based on the baseband signal from said FM demodulating means (4) in response to the determination by said determining means (10) that said received television signal does not include said carrier.
Claim 8
Dependent Claim
79 words
The tuner according to claim 6, which further comprises second switching means (20) for coupling said first automatic frequency adjusting means (21) to said converting means (3) in response to the determination by said determining means (10) that said received television signal includes said carrier while coupling said second automatic frequency adjusting means (22) to said converting means (3) in response to the determination by said determining means (10) that said received television signal does not include said carrier.
Claim 9
Dependent Claim
37 words
The tuner according to claim 2, wherein said determining means (10) further comprises filter means (12) for extracting the sound signal included in said received television signal, to apply the same to said out-of-synchronization detecting means (14).
Claim 10
Dependent Claim
32 words
The tuner according to claim 5, wherein said determining means (10) further comprises filter means (12) for extracting the sound signal from the baseband signal applied from said FM demodulating means (4).
Claim 11
Dependent Claim
36 words
The tuner according to claim 2, wherein said first automatic frequency adjusting means comprises an averaging automatic frequency adjusting circuit (21), and the second automatic frequency adjusting means comprises a keyed automatic frequency adjusting circuit (22).
Claim 12
Dependent Claim
130 words
A tuner circuit which is capable of receiving and processing television signals transmitted in both first and second TV transmission systems, the first system involving frequency division multiplexing sound and video signals and the second system involving time-divisional multiplexing sound and video signals, the circuit having first and second processing means for respectively processing the first and second system signals, means for determining whether a received TV signal is a said first or second system signal by detecting the presence or absence in the received signal of the sound signal carrier used in a said first system signal, and means for selectively directing the received signal to said first or second processing means under the control of the determining means according to the system to which the received signal belongs.
Claim 13
Dependent Claim
130 words
A tuner circuit which is capable of receiving and processing television signals transmitted in both first and second TV transmission systems, the first system involving frequency division multiplexing sound and video signals and the second system involving time-divisional multiplexing sound and video signals, the circuit having first and second processing means for respectively processing the first and second system signals, means for determining whether a received TV signal is a said first or second system signal by detecting the presence or absence in the received signal of the sound signal carrier used in a said first system signal, and means for selectively directing the received signal to said first or second processing means under the control of the determining means according to the system to which the received signal belongs.
References Cited (Backward Citations)
No citation records indexed.
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