JPS5827473A - Television signal output device - Google Patents

Abstract

PURPOSE:To decrease the number of signal output terminals for convenience, by supplying an RF output of a signal processing section to one input terminal of a signal mixing circuit and a video outut from a signal processing section to another input terminal, respectively. CONSTITUTION:A video signal 2 outputted from a signal processing section 1 is inputted to one input terminal of a signal mixing circuit 17. Further, an RF signal 6 outputted from a processing section 1 is also inptted to another input terminal of the circuit 17. The signal 2 and 6 are mixed at the circuit 17 to be a signal 18 and the signal 18 is outputted from an output terminal 19. A sound signal 4 outputted from the processing section 1 is outputted from an output terminal 5 as it is. Thus, the number of the output terminals of a TV signal output device 20 can be decreased by one.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is applicable to a video recorder, a video disc playback device, or a television signal (hereinafter referred to as RF multiplied signal) which is obtained by modulating a carrier wave with a video signal or another video signal. A video signal and an RF multiplied signal, such as a personal computer whose output device is a television set with a video signal input terminal (hereinafter referred to as a home TV) or a television set with a video signal input terminal (hereinafter referred to as a monitor TV). Alternatively, the present invention relates to a television signal output device that outputs a video signal, an audio signal, an RF multiplied signal, and the like.

Figure 1 shows a conventional example. To explain this, numeral 1 is a signal processing section in a device that outputs a video signal, an audio signal, and an RF multiplied signal. Reference numeral 2 denotes a video signal output from the signal processing section 1, which is supplied to a video signal output terminal 3. 4 is an audio signal outputted from the signal processing section 1 as well, and is supplied to the audio signal output terminal 5. 6 is also supplied with the RF multiplied signal outputted from the signal processing section 1 and the RF signal output terminal 7.

The television signal output device 8 is configured as described above.

Here, the RFF number 6 is a signal obtained by modulating a carrier wave with a video signal different from the video signal 2.

Now, when using the above television signal output device 8, either connect a home TV to it or use a monitor T.
The connection method differs depending on whether V is connected. This will be explained with reference to FIGS. 2 and 3.

FIG. 2 shows a television signal output device 8 connected to a home TV.
Shows when connecting. In the figure, 9 is a home TV, 1o is its RF signal input terminal, and is connected to the RFF signal output terminal 7 via a coaxial cable 11. However, FIG. 3 shows a case where a monitor TV is connected to the television signal output device 8. In the figure, 12 is a monitor TV, 13 is its video signal input terminal, and 14 is an audio signal input terminal. In this case, the 13 video signal input terminals 13 and the video signal output terminals 3 are connected to the coaxial cable 16.
and connect the audio signal input terminal 14 and the audio signal output terminal 6.
It is connected with cable 16.

As described above, the user uses the television signal output device 8.
Depending on the input format of the television set to be connected to, the three output terminals 3, 6.7 of the television signal output device 8
The more necessary output terminal must be selected. This means that the television signal output device 8
This is a major cause of confusion regarding how to connect the TV set to the TV set. Furthermore, as television signal output devices become smaller, the provision of three output terminals places restrictions on component placement in mechanical design.

The present invention solves the above-mentioned problems by reducing the number of signal output terminals, thereby making it possible to reduce the manufacturing cost of the device. Hereinafter, the present invention will be explained based on illustrated embodiments.

In FIG. 4, a video signal 2 output from the signal processing section 1 is input to one input terminal of a signal mixing circuit 17.

Similarly, the RFF signal 6 output from the signal processing section 1 is also input to the other input terminal of the signal mixing circuit 17. Signals 2 and 6 are mixed in the signal mixing circuit 17 to form a signal 18, which is output from an output terminal 19. Further, the audio signal 4 outputted from the signal processing section 1 is outputted as is from the output terminal 6. The television signal output device 2o is configured as described above.

With the above configuration, the number of output terminals can be reduced by one compared to the conventional example shown in FIG. This reduces the output terminal cost and reduces the output terminal space, increasing the degree of freedom in designing the two mechanisms. 1. Even when the user connects the television signal output device 20 and the television set, the method of connection becomes clear.

This will be explained with reference to FIGS. 5 and 6. Fifth
The figure shows an example of connecting the television signal output device 20 and a home TV. In this case, as shown in the figure, the RFF signal input terminal 1o of the home TVs and the video signal and RFF signal output terminal 19 of the television signal output device 20 are connected by a coaxial cable 11.

Figure 6 shows the television signal output device 20 and monitor TV.
An example of connecting is shown. In this case, monitor TV1
The video signal input terminal 13 of the TV signal output device 2o and the output terminal 19 of the television signal output device 2o are connected with the coaxial cable 16, and the audio signal input terminal 14 and the audio signal output terminal 5 are connected with the cable 16.
Connect with.

That is, the RF signal input terminal of the television set connected to the television signal output device 20.

or video signal input terminal refers to both video signal and RF
It suffices to connect it to the signal output terminal 19, and if an audio signal is required, such as in a monitor TV, a signal can be obtained from the output terminal 6. in this way.

The connection between the television signal output device 2o and the television set is simple and eliminates the trouble and confusion of selecting the necessary output terminal according to the television set to be connected as in the past. It is.

Note that there is a good possibility that the video signal and the RF multiplied signal exist simultaneously at the output terminal 19 of the television signal output device 20, but they do not affect each other. The reason is that, as shown in FIG. 5, when a home TV is connected to the television signal output device 20, the video signal output from the output terminal 19 becomes an unnecessary signal for the home TV 9. This is outside the required signal band and has no effect. Also, as shown in Figure 6, monitor TV1
When connecting 2, the RF output from output terminal 19
This is because although the doubled signal is an unnecessary signal, it is outside the necessary signal band in this case as well, and there is no influence in the same way as above.

FIG. 7 shows an example of the configuration of the signal mixing circuit 17.

In the same figure, video signal 2 and RF signal 6 are connected to resistors R1 and R
2 and input to the base of transistor Q.

Transistor Q acts as an emitter follower, and the mixed signal is taken out from the emitter of transistor Q through resistor R3. Here, the resistor R3 is provided for the purpose of impedance matching with the coaxial cable connected to the output terminal 19. As described above, the signal mixing circuit 17 can be realized by a simple resistance adding circuit.

Another example of the configuration of the signal mixing circuit 17 is shown in FIGS. 8(a) and 8(fb). In the figure (a), a low-pass filter 21 is connected to the video signal 2, a bypass filter 22 is connected to the RF signal 6, and the mixed signal 18 is obtained by adding the outputs of these. In particular, the low-pass filter 21 is a π-type filter consisting of an inductor L and a capacitor C1, and the high-pass filter 22 is L
2. Although it is configured with a C2 π-type filter, it may be configured with a filter of another type. In addition, in the configuration example shown in FIG. 3(b), the low-pass filter 2 is simply
1' and a capacitor C3 serve as a bypass filter 22'.

This means that the frequency band of the video signal is different in each of the NTSC, PAL, and SECAM television signal systems.

10 MHz or less than direct current, while RF
The doubled signal is around 50 MHz or higher even in other countries, and is sufficiently far away on the frequency axis, so it can be realized using the simple method described above.

Another embodiment of the invention is shown in FIG. In the figure, a video signal 2 output from a signal processing section 1 is transmitted to a signal mixing circuit 2.
The signal is input to the first input terminal of No. 3.

Similarly, the RF signal 6 output from the signal processing section 1 is also input to the second input terminal of the signal mixing circuit 23.

Furthermore, the audio signal 4 output from the signal processing section 1 is input to the audio signal modulation circuit 24 . Here, a signal 25 is obtained by modulating the carrier wave with the audio signal 4. This signal 26 is input to the third input terminal of the signal mixing circuit 23 to obtain a signal 26 which is a mixture of the signals 2, 6, and 25, and is output from the output terminal 27. With the above, the television signal output device 2
8 is composed. Here, the carrier wave of signal 26 is
5! The frequency spectrum of the video signal 2 and the RF signal 6 are selected so that they are located between the respective frequency spectra of the video signal 2 and the RF signal 6 on the frequency axis.

Both the video signal 2 and the modulated audio signal 26 are
Since it is outside the required signal band of V9, it has no effect on it. Further, FIG. 11 shows a case where the television signal output device 28 and a monitor TV are connected. In this case, the output terminal 27 of the television signal output device 28
and the video signal input terminal 13' of the monitor TV 12' are connected by a coaxial cable 16. However, in this case, it is necessary to provide a circuit for separating and demodulating the modulated audio signal 25 from the signal input from the video signal input terminal 13' in the monitor TV 12'. Shi, Kaji, Monitor TV12'
In this case, if the audio signal is not required, the above-mentioned modulated audio signal separation/demodulation circuit is not required.

In the television signal output device 28 shown in FIG. 9, the signal mixing circuit 23 can be configured with a resistor addition circuit as shown in FIG. 7, but it is also possible to use a filter as shown in FIG. It can also be used for things. In the figure, 29 is a low-pass filter to which the video signal 2 is input. Still, 30 is a band pass filter, into which the modulated audio signal 26 is input. 31 is an I-pass filter, R
F signal 6 is input. Each of the above filters 29, 30, 3
1 serves as a passband for the input signal and a stopband for other signals. Therefore, by adding the outputs of the three filters 29., 30.31, respectively, the video signal 2. Modulated audio signal 25. RF
By mixing the three signals of signal 6, signal 27 can be obtained.

FIG. 13 shows yet another embodiment of the present invention. This is the 9th
In addition to the configuration shown in the figure, the audio signal 4 output from the signal processing section 1 is also supplied to the output terminal 6.

The television signal output device 32 configured in this manner can also be connected to a monitor TV that has 14 audio signal input terminals 14 and requires input of the audio signal 4, like the monitor TV 12 in FIG. be.

As is clear from the above description, two aspects of the present invention are a video tape recorder and a video disc playback device.

Alternatively, it reduces the number of output terminals for video signals, audio signals, RF multiplied signals, etc. used in personal computers, thereby reducing the cost of output terminals and the mechanical design of the device by reducing the output terminal space. In addition to improving the degree of freedom as described above, it is possible to prevent confusion due to connection terminal selection when connecting the device and a television set, and it is possible to provide the user with an easy-to-use device.

[Brief explanation of the drawing]

FIG. 1 is a circuit configuration diagram of a conventional television signal output device, FIGS. 2 and 3 are schematic diagrams showing a method of connecting the conventional device and a television set, and FIG. 4 is an embodiment of the present invention. Example circuit configuration diagrams, FIGS. 5 and 6 are schematic diagrams showing how to connect the device in FIG. 4 and a television set, and FIG.
8(a) and 8(b) are circuit diagrams showing a configuration example of a signal mixing circuit that can be used in the present invention, FIG. 9 is a circuit configuration diagram showing another embodiment of the present invention, and FIG. 10 and the 11th
9 is a schematic diagram showing a method of connecting the device of FIG. 9 and a television set, FIG. 12 is a circuit configuration diagram showing another example of a signal mixing circuit that can be used in the present invention, and FIG. FIG. 3 is a circuit configuration diagram showing another example. 1...signal processing section, 2...video signal, 4...audio signal, 6...audio signal output terminal, 6... ... Signal obtained by modulating the carrier wave with the video signal (RF multiplied signal, 17, 23 ... Signal mixing circuit, 18.26 ... Signal mixing circuit output, 1
9.27... Signal mixing circuit output signal output terminal, 20.28, 32... Television signal output device, 21.21'. 29...Low pass filter, 22.22', 3
1...no pass filter, 24...
Audio signal modulation circuit, 25...Modulated audio signal, 3
o・・・・・・ノ(nd pass filter) Name of agent: Patent attorney Toshio Nakao and one other person, etc.
1 Figure 12 Figure 131! 1 Figure 4 0 Figure 5 Figure 6 0 Figure 7 Figure 8 ? 1 21 Pa''22・Figure 9Figure 10Figure 11R

Claims (1)

[Scope of Claims] (1) A signal processing unit that outputs a video signal and a television signal obtained by modulating a carrier wave with the video signal or another video signal, and a signal mixing circuit that mixes a plurality of signals. By supplying the video signal and the television signal output from the signal processing section to the signal mixing circuit, a signal obtained by mixing the video signal and the television signal is output from the output side of the signal mixing circuit. 1. A television signal output device characterized in that the television signal output device is configured to output multiple mixed signals from the same output terminal. (2. In the description of claim (1), the signal mixing circuit is also supplied with a modulated audio signal obtained by modulating a carrier wave different from the carrier wave of the television signal with an audio signal, and A television signal output device characterized in that a signal obtained by mixing the video signal, the modulated audio signal, and the television signal is obtained from a circuit and outputted from the same output terminal. (3) In claim (1), the signal mixing circuit includes a low-pass filter and a no-pass filter, and the video signal is input to the low-pass filter, and the television signal is input to the low-pass filter. A television signal output device characterized in that the television signal output device is configured to input to a bypass filter and add the output of the low-pass filter and the output of the bypass filter. (4) Claim (2) In the description, the signal mixing circuit includes a low-pass filter, a band-pass filter, and a no-pass filter, and the video signal is input to the low-pass filter, and the modulated audio signal is input to the band-pass filter. , the television signal is input to the bypass filter,
A television signal output device characterized in that it is configured to add the output of the low-pass filter, the output of the band-pass filter, and the output of the bypass filter.