JPH077441A - Compact receiver - Google Patents

Abstract

PURPOSE:To provide a compact receiver having a diversity system capable of inexpensively receiving broadcasting radio waves in its optimum state without making its constitution large in scale. CONSTITUTION:Two earphone cords of earphones 10 connected to a sound circuit 13 are utilized as the 1st and 2nd antennas 101, 102, the input levels of the antennas 101, 102 are applied to sampling and holding circuits 171, 172 in a control circuit 17, outputs from the circuits 171, 172 are mutually compared by a comparator circuit 173, and the compared result is applied to a switch 111 to select the antenna 101 or 102 having a larger output level.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a portable television receiver or the like, and a small receiver provided with a diversity system for selecting and switching an antenna for receiving the best broadcast radio wave among a plurality of antennas.

[0002]

2. Description of the Related Art Recently, portable small television receivers and the like are often used in trains and the like, but when the television receiver moves due to traveling of the train, radio waves are generated due to the surrounding electric field state. Since the reception conditions of fluctuate greatly, it may not be possible to stably receive a television broadcast.

Therefore, conventionally, it has been considered to use a diversity system in which a plurality of antennas are used and the antenna that receives the best broadcast radio wave is selected from the plurality of antennas.

However, conventionally, in the diversity system adopted in such a small television receiver, a plurality of dedicated antennas are connected to the television receiver to receive the best broadcast radio wave among the plurality of antennas. I try to choose one.

[0005]

However, the provision of a plurality of dedicated antennas for such a small television receiver is not only costly in terms of the overall configuration but also costly. There was a problem.

The present invention has been made in view of the above circumstances, and has a diversity system that does not require a large configuration, is inexpensive in price, and is capable of receiving broadcast waves in the best condition. It is an object to provide a small receiver.

[0007]

SUMMARY OF THE INVENTION The present invention comprises a receiver main body, an earphone connected to the receiver main body, having at least two cords, and using the cords as an antenna. It is composed of selecting means for comparing the input levels of the antennas and selecting the antenna with the higher input level.

[0008]

As a result, according to the present invention, at least two earphone cords of the earphones connected to the receiver main body are used as antennas, respectively, and the input levels of these antennas are compared with each other to use the one having a large input level. As a result, the radio wave can always be captured in the best condition, and the overall configuration does not become large,
It can be cheap in price.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic configuration when the present invention is applied to a small liquid crystal television. In the figure, numeral 11 is a tuner, and this tuner 11 includes antennas 101 and 1 to be described later.
The broadcast wave received in 02 is taken in, a designated channel is selected according to the tuning signal from the control circuit 17, and is converted into an intermediate frequency signal.

The intermediate frequency signal output from the tuner 11 is applied to the TV linear circuit 12. The TV linear circuit 12 has an intermediate frequency amplification circuit, a video detection circuit, a video amplification circuit, an AFT detection circuit, and the like, amplifies the intermediate frequency signal given from the tuner 11, and detects the video signal to detect the intermediate frequency signal. An audio signal is taken out from the output signal and given to the audio circuit 13.

The audio circuit 13 has an audio detection circuit and an audio amplification circuit, detects an audio signal supplied from the TV linear circuit 12 and converts it into a low frequency signal, and amplifies the audio to drive the speaker 14. I am trying.

A stereo type earphone 10, for example, can be connected to the voice circuit 13 so that voice can be output instead of the speaker 14.
In this case, the earphone 10 includes two earphone cords in the first and second antennas 101 and 102, and the first and second antennas 101 and 102 are provided.
Is connected to the tuner 11 via the switch 111. In addition, these first and second antennas 101, 1
The input level of 02 is also applied to the control circuit 17.

The TV linear circuit 12 amplifies the output signal of the video detection circuit by the video amplification circuit, and then the chroma circuit 15,
It is applied to the cycle separation circuit 16. Also TV
The linear circuit 12 AF outputs the output signal of the intermediate frequency amplifier circuit.
AFT detection is performed by the T detection circuit, and an S-shaped AFT signal is extracted and given to the control circuit 17.

The cycle separation circuit 16 separates the horizontal and vertical sync signals included in the video signal into a composite sync signal C-SY.
NC is given to the control circuit 17 and the horizontal synchronizing signal H
-SYNC and the vertical synchronizing signal V-SYNC are applied to the timing control circuit 18.

The control circuit 17 is provided with key input data such as key setting data and tuning up / down instruction from the key input unit 19, and these key setting data and tuning up / down instruction and the AFT from the TV linear circuit 12 are supplied. A tuning signal is generated based on the signal and given to the tuner 11.

Further, the control circuit 17 controls the earphone 1
Sample hold circuits 171 and 172 for holding the input levels of the first and second antennas 101 and 102 each composed of a pair of 0 earphone codes.
And a comparison circuit 173 for comparing and selecting one of the output levels of the sample hold circuits 171 and 172, which has a higher level. The comparison result of the comparison circuit 173 is given to the switch 111 as an antenna switching signal. .

The timing control circuit 18 has a sampling signal φ based on the horizontal sync signal H-SYNC and the vertical sync signal V-SYNC provided from the sync separation circuit 16.
s is created and given to the A / D conversion circuit 20.

The A / D conversion circuit 20 samples the chroma signal output from the chroma circuit 15 based on the sampling signal φs, converts it into digital data of 3 to 4 bits, and supplies it to the segment driver 21. There is. Further, the timing control circuit 18 generates a timing signal for display control based on the synchronization signal given from the synchronization separation circuit 16 and controls the operation of the segment driver 21 and the common driver 22.

In this case, the common driver 22 generates a scanning signal according to the timing signal from the timing control circuit 18 and sequentially drives the common electrodes of the LC panel 23, and the segment driver 21 supplies it from the A / D conversion circuit 20. 3 to 4 bits of video data are sequentially read by the timing signal of the timing control circuit 18 and one line of video data is read, and then a gradation signal is created according to the video data, and the segment electrodes of the LC panel 23 Is driven to display.

In the liquid crystal television thus constructed, the user holds the television main body 30 by hand, as shown in FIG. 2, for example, in a train, and attaches the earphone 10 connected to the television main body 30. Used with both ears inserted.

Now, suppose that the first and second antennas 101, which consist of two earphone cords of the earphone 10,
If the first antenna 101 of 102 is selected, the radio waves received by the first antenna 101 are taken into the tuner and the designated channel is selected. Then, the intermediate frequency signal of this designated channel is transmitted to the TV.
The audio signal is sent to the linear circuit 12, the audio signal is given from the TV linear circuit 12 to the audio circuit 13, and the audio is transmitted to the earphone 10.
Will be output. Further, the image detection signal is given from the TV linear circuit 12 to the chroma circuit 15 and the period separation circuit 16. The chroma signal from the chroma circuit 15 is A /
It is supplied to the D conversion circuit 20, converted into a digital signal by the sampling signal φs of the timing control circuit 18, and supplied to the segment driver 21. When a timing signal for display control is given from the timing control circuit 18 to the segment driver 21 and the common driver 22, the common driver 22 drives the common electrode of the LC panel 23, and the segment driver 21 performs A / D conversion. Each time the digital signal from the circuit 20 is read and the video data for one line is read, the segment electrodes of the LC panel 23 are driven,
The received image is displayed on the panel 23.

In this state, the first and second antennas 10 each consisting of a pair of earphone cords of the earphone 10.
The respective input levels of 1 and 102 are given to the sample hold circuits 171 and 172 of the control circuit 17 and held respectively. The outputs of the sample hold circuits 171 and 172 are given to the comparison circuit 173. In the comparison circuit 173, the sample hold circuit 17
One of the output levels from 1 and 172 is selected to have a higher level, and the comparison result is provided to the switch 111 as an antenna switching signal.

As a timing at which this antenna switching signal is given, a period during which no image is displayed, for example, a vertical retrace line period is used. As a result, if the input level of the second antenna 102 is lower than that of the first antenna 101 that is currently connected, the connection of the first antenna 101 to the tuner 11 is maintained, and the second antenna 102 is maintained. When the input level of the antenna 102 increases, the second antenna 102 is selected this time and connected to the tuner 11. In this way, the first and second
The input levels of the antennas 101 and 102 are constantly compared, and the one with a large input level is connected to the tuner 11, whereby the best broadcast wave can be captured and stable TV broadcast can be received. become.

Therefore, in this way, the two earphone cords of the stereo type earphone 10 connected to the television body are connected to the first and second antennas 101 and 10.
The first and second antennas 10 are used as
Since the input levels of 1 and 102 are compared and the one with the higher input level is used, the radio wave can always be captured in the best state, and the television broadcast can be stably received.

Further, since the two earphone cords of the earphone 10 are used as the first and second antennas 101 and 102, the entire structure becomes large as compared with the conventional dedicated antenna. It can be made cheaper in price.

The present invention is not limited to the above-mentioned embodiments, but can be carried out by appropriately modifying it within the scope of the invention.
For example, in the above-described embodiment, the portable liquid crystal television is described, but the present invention can be applied to other small receivers such as a portable FM receiver. In addition, although the stereo type earphone has been described in the above-described embodiment, a monaural type binaural earphone is also applicable. Furthermore, by adding a cable in the middle of the earphone cord (for example, between the earphone and the remote controller operation unit when there is a remote controller operation unit in the middle of the cord), a higher frequency antenna can be configured. Further, by providing an antenna with a plurality of lead wires in addition to the earphone cord used as the antenna, the accuracy of the diversity system can be further improved.

[0027]

According to the present invention, at least two earphone cords of the earphones connected to the receiver main body are used as antennas, respectively, and the input levels of these antennas are compared with each other to use the one with a large input level. Since this is done, it is possible to always capture the radio waves in the best condition, and to stably receive broadcasts and the like. Moreover, since there is no need to prepare a plurality of dedicated antennas, the overall configuration does not become large and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of an embodiment of the present invention.

FIG. 2 is a diagram showing an actual usage state.

[Explanation of symbols]

10 ... Earphones, 101, 102 ... Antennas, 11 ...
Tuner, 111 ... Switching device, 12 ... TV linear circuit,
13 ... Voice circuit, 14 ... Speaker, 15 ... Chroma circuit,
16 ... Cycle separation circuit, 17 ... Control circuit, 171, 172
... sample-hold circuit, 173 ... comparison circuit, 18 ... timing control circuit, 19 ... key input section, 20 ... A / D conversion circuit, 21 ... segment driver, 22 ... common driver, 23 ... LC panel.

Claims (1)

[Claims] 1. An input level of a receiver main body, an earphone connected to the receiver main body and having at least two cords and using the cords as an antenna, and an input level of each antenna composed of the cords of the earphones are compared to compare the input level. A small receiver comprising: a selection unit for selecting an antenna having a large input level.