JPS6016153B2 - Multiplex broadcast reception adapter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION An object of the present invention is to provide a multiplex broadcast receiving adapter that can display and emit video signals, character signals, and audio multiplex signals on a television receiver.

below,. An embodiment of the present invention will be described based on the drawings.

FIG. 1 is a block diagram of an embodiment of the invention.

1 is a tuner, 2 is Vm, 3 is a video detection circuit, 4 is a signal switching circuit, 5 is a video and color signal processing circuit, 6 is an amplifier,
7 is a cathode ray tube, 8 is S', 9 is an FM detection circuit, 10 is a changeover switch, 11 is an amplifier, 12 is a speaker, 4
Except for this, it is the same as a color TV with audio multiplex terminal.

On the other hand, 13 is a multiplex signal reception adapter of the present invention. 2
1 is a tuner, 22 is a V mark, 23 is a video detection circuit, 29
is the same signal processing circuit as 5; 24 is a character signal receiving circuit that receives character information multiplexed with the television signal; and 26
is a demodulation circuit for audio multiplexed signals, and outputs the main and Liu sounds.

When the outputs of the demodulation circuit 26 and the character signal receiving circuit 24 are added to the switching circuit 4 and the switching switch, character information is displayed on the cathode ray tube 7, and main or sub audio is output from the speaker 12. In such a configuration, in order to improve the demodulation performance of audio multiplexing, the input of the demodulation circuit 26 is obtained from the tuner 21, the audio signal is amplified and detected using a so-called separate carrier method, and the audio subcarrier and pilot Amplify the carrier, detect it, and output the required audio signal. on the other hand,
For reception of character signals, it is desirable to use wideband tuner 21 and VIF 22 and synchronous detection, and character signals can be easily reproduced if slight deterioration in image quality is ignored. Character signal receiving circuit 2
4 output as a video signal or R (red signal), G (green signal),
B (green signal), if input to the parent television, characters and figures will be displayed on the cathode ray tube 7. Furthermore, if the character signal is modulated to a high frequency by the high frequency modulation circuit 25 and applied to the tuner, the characters can be displayed on the cathode ray tube 7 even without the switching circuit 4, and the sound can be output from the two speakers 12 and 28. obtain.
The features of this device are that good characters and graphics are displayed on the cathode ray tube 7 regardless of the performance of the parent TV's VIF2 or earlier, and that audio multiplexed signals are reproduced regardless of the performance of the parent TV's SIF, etc. The advantage is that it can be displayed and output to the cathode ray tube 7 and speakers of the parent television. Since the sounds are separated, when the output of the character signal receiving circuit 24 is re-modulated by the high frequency modulation circuit 25, the sound is not necessary. When the changeover switch 1 is inserted with the plug of the adapter 13, it becomes an a-c short circuit and b-c opens, and when the adapter 13 is not connected, it becomes a b-c short circuit.

The two outputs of the demodulator 26 are the pilot carriers
．． When it is modulated at 5/2, it becomes a stereo sound of L (left signal) and R (right signal), and when it is modulated at 922.5 Hz, it becomes a stereo sound of main and sub (different content such as Japanese and English). It is the same as what is known as an audio multiplex adapter, in that it becomes the same signal (monaural signal) in both directions when there is no modulation. Next, a case will be described in which it is necessary to superimpose text information and the referee's screen. 24 in Figure 2
' is the part obtained by removing 30R, 30G, and 30B from 24. In this case, although the tuner 21 and VIF 22 cannot be made to have a very wide band, if 23 is made into a synchronous detection circuit, the pulse characteristics will be improved. The output of the signal processing circuit 29 is the R, G, B color signals of the main program, and the output of the signal processing circuit 24' is the control signal and the R, G, B color signals.
These are G and B character signals. The output of the analog OR gate 31 is the R character signal superimposed on the R signal of the main program, and if the operation of the character receiving section indicates a superimposed display, the output of the inverter 35 becomes a high level. Then, the analog AND gate 32 becomes conductive and the AND gate 33 is cut off.

Numeral 34 is an analog OR gate, and when superimposed display is being performed, it is naturally a character reception state, so the analog AND gate 37 is conductive.
The output of the inverter 39 becomes low level and the analog AN
D gate 36 is cut off and the output of OR gate 38 is OR
This is the output from the gate 31.

4R, 4G, and 4B are switches that operate in conjunction with the selector switch 10, and because of the a-c short circuit, the output of the OR gate 31 is transmitted to the amplifier 6.

G and B are also the same aircraft (30G and 30B have the same content as 30R). Therefore, the cathode ray tube 7 displays a screen on which characters are superimposed on the main program screen. Also, 3
It is also possible to encode the signal with 0 to form a composite video signal and supply it to the tuner 1 via the high frequency modulation circuit 25. In this case, the changeover switches 4R, 4G, and 4B must be short-circuited. This divides the connection terminal into two, and divides it into a selector switch 10 and 4R, 4G, 4B.
It is sufficient if the signal from the tuner 21 is displayed on the cathode ray tube 7 without being connected to the channel. If only characters are displayed, use AND gate 32
is cut off, AND 33 is turned on, and when only the main program is displayed, the AND gate 37 is cut off and the AND gate 36 is turned on, so that only - characters or only the main program are displayed on the cathode ray tube. Note that text reception and voice multiplex reception can be performed completely independently.

Another feature is that the existing terminal set can be used as a mere display cathode ray tube and speaker, and all controls can be performed using the adapter 13. It is also conceivable to add one more set of amplifier 27 and speaker 28 and not use the set of amplifier 11 and speaker 12. As described above, the present invention includes a tuner, an intermediate frequency amplifier that amplifies the output of this tuner, a video detection circuit that detects a video signal being output from this intermediate frequency amplifier, and a video signal included in the output of this video detection circuit. A character signal receiving circuit that receives character information multiplexed with the television signal and sent, a demodulation circuit that demodulates the main audio signal being output from the intermediate frequency amplification circuit, and a main and sub-channel of this demodulation circuit. A multiplex broadcast receiving adapter comprising an amplifier for amplifying at least one of the audio outputs, a speaker for emitting the output of the amplifier, and a terminal for supplying the output of the character signal receiving circuit to another television receiver. By simply connecting an adapter to a television receiver, text signals can be displayed, and audio multiplexed signals can also be emitted.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a multiplex broadcast receiving adapter and a receiver according to an embodiment of the present invention, and FIG. 2 is a specific block diagram of the main parts of the adapter. 13...Adapter, 21...Tuner, 22...VIF, 23
...Video detection circuit, 29...Signal processing circuit, 24...Character signal receiving circuit, 26...Demodulation circuit, 27...Amplifier, 28...Speaker, 25...High frequency modulation circuit. Figure 1 Figure 2

Claims (1)

[Claims] 1. A tuner, an intermediate frequency amplifier that amplifies the output of this tuner, a video detection circuit that detects the video signal being output from this intermediate frequency amplifier, and a video signal that is multiplexed with the television signal contained in the output of this video detection circuit. A character signal receiving circuit that receives the sent character information, a signal processing circuit that extracts R, G, and B color signals of the main program from the output of the video detection circuit, and a character signal receiving circuit provided in the character signal receiving circuit. means for superimposing the R, G, B color signals representing the character signal with the signal processing circuit or for extracting the R, G, B color signals representing the character signal independently; and the intermediate frequency amplifying circuit. A demodulation circuit that demodulates the main and sub audio signals being output, an amplifier that amplifies at least one of the main and sub audio outputs of this demodulation circuit, a speaker that emits the output of this amplifier, and another television receiver. and a terminal for supplying the output of the character signal receiving circuit.