JPH06204804A - Channel selecting device - Google Patents

Abstract

PURPOSE:To shorten preset time, to improve operability and to save the power of band switching operation by controlling tuning operation in accordance with channel information. CONSTITUTION:A position for storing tuning voltage data in a memory 711 is specified by inputting the position by an input means 702 in accordance with a picture displayed by a display means 703. A band to be searched is switched, the band of a tuner 708 is switched by means of a band switching circuit 709 and then auto-searching is executed by searching the tuning voltage of the tuner 708 from a microcomputer 701 by means of a D/A converter 710. When a synchronizing signal is inputted from a synchronizing signal processor 705 and an automatic fine tuning (AFT) voltage inputted from a video intermediate frequency signal processor 706 to the microprocessor 701 is optimum, the stop of the search is judged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television receiver, and more particularly to a channel selection device for a television receiver.

[0002]

2. Description of the Related Art In broadcasting such as TV, a carrier frequency that can be used is assigned to each broadcasting station. The above is called a channel plan, and each broadcasting station was broadcasting according to this. In TV broadcasting, the carrier frequency band is
VHF (Very High frequency), UHF (Ultra High fre
quency). Therefore, in order for a viewer to view a specific broadcast station, the carrier frequency and band assigned to the specific broadcast station must be set in advance. After the setting (hereinafter referred to as channel preset) was completed, the broadcasting of a specific broadcasting station was selected by a remote control unit (hereinafter referred to as a remote controller) or a switch.

FIG. 6 shows a processing procedure when a voltage synthesizer system is used for channel presetting of a conventional TV or the like.

The processing procedure when the voltage synthesizer method is used for the conventional channel preset will be described with reference to FIG. In the normal mode (normal state) (step 601), while viewing on a TV or the like, the channel is switched to the channel preset mode (602) by a switch or the like in order to preset the channel. Position input to specify the location to be stored in memory (step 60
Perform 3). Next, the band switching input (step 60)
4) is performed, but when the voltage synthesizer method is used, the band is designated by the tuner band (VL, VH,
This is done by switching U). If the currently designated band is acceptable, an automatic search (step 606) is performed, and if a band other than the currently designated band is selected, band switching (step 605) is performed. The operation of the auto search (step 606) sequentially changes the value of the PWM (Palse Width Mojulation) output output from the microcomputer to the tuner to control the tuning voltage of the tuner.
During the execution of the automatic search (step 606), when the synchronizing signal is input and the AFT (Automatic Fine Tuning) voltage is at the best point, the automatic search is stopped (step 607). At this time, the state of the TV screen is the best (step 60
If it is not 8), the fine adjustment operation (step 609) is performed to obtain the best state.

[0005]

In the conventional channel preset method, as described above, the operation of switching the band by the switch or the like and the operation of searching the full range of the tuning voltage of each of VL, VH, U are performed. There is a problem that it takes time and the operability is bad in order to preset all the channels. In addition, there is a problem that a person must perform the operation of switching the band. Therefore, an object of the present invention is to provide a channel selection device that shortens preset time, improves operability, and saves labor in band switching operation in a relatively simple manner.

[0006]

In order to solve the above problems, in a tuning device using a voltage synthesizer method as a tuning method, a storage means for storing channel information necessary for performing tuning control is provided. , A display means for displaying a screen in a menu format at the time of channel presetting, an input means for a user to input according to the menu screen displayed by the display means, and a selection for controlling a tuning operation according to channel information called from the storage means. There is provided a channel selection device including station control means.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a processing procedure of an embodiment of the present invention will be described with reference to FIG. From the state of the normal mode (step 101), the mode is changed to the preset mode (step 102) by an input means such as a switch or a remote controller. Next, the position number, the channel number to be selected and the channel number to be displayed on the screen (these three are referred to as channel information) are input (step 103). You have entered all the channel information (Step 10
After confirming 4), auto search (step 105)
I do. At this time, the operation of performing an automatic search determines the band (VL, VH, U) and the search range from the channel number to be originally selected according to the channel plan. The microcomputer monitors the sync signal input and the AFT voltage, and stops the search when the sync signal is input and the AFT voltage is at the best point (step 106). With the search stopped, if the state of the screen is not the best visually (step 107), fine adjustment is performed (step 109).
The operations of (step 105) to (step 108) are performed for the number of input channel information items.

Next, the operation of this embodiment will be described according to the processing procedure with reference to FIG. Start tuning operation (Step 4
From 01), it is judged whether or not to shift to the preset mode by the input from the input means in the normal state (step 402). If it is in the preset mode, it is determined whether the channel information is stored in the memory before the start of the tuning operation (step 403). If it is not in the preset mode, the tuning operation is ended (step 425).

If the channel information is stored in the memory, the channel information stored in the memory is displayed (step 404) and the band output data and the tuning voltage data are output based on the selected channel information. After that (step 405), the process proceeds to the determination routine for updating the channel information (step 406). If the channel information is not stored in the memory, immediately proceed to (step 406).

When updating the channel information, the position to be stored in the memory is input (step 407), the channel number to be selected is input (step 408), and the display number to be displayed on the screen is input (step 409). .

If the channel information is not updated, the tuning operation is ended (step 425). Next, it is judged whether the input of the channel information to be updated is completed (step 41
0), when finished, the updated channel information is stored in the memory (step 411), and when not finished, the operations of (step 407) to (step 410) are repeated. After (step 411), for one of the updated channel information, the control range of band data and tuning voltage data is determined using the channel plan based on the channel number in the channel information. At this time,
As a method of determining, the band (VL, VH, U) is first determined from the channel number, and similarly the value of the tuning voltage of the channel to be selected is known from the channel number. The center value of the tuning voltage data is calculated from the tuning voltage, and the carrier frequency is searched so as to be −several MHz to center value to + several MHz. The control of the search range is performed by the PWM output that controls the tuning voltage from the microcomputer. After determining the control range of the band data and the tuning voltage data (step 412), the band data is output and the tuning voltage is searched (step 413). During the search, the sync signal input (step 414) and the AFT voltage (step 415) are monitored, and there is a sync signal input and A
When the FT voltage is at the best point, the search is stopped (416). When the search is stopped, it is visually judged whether or not the screen state is the best point (step 417). If the screen state is the best point, the tuning voltage at that time is stored in the memory. If the state of the screen is not the best point, the tuning voltage is finely adjusted (step 41
9, step 420), the tuning voltage is finely adjusted, and when the state of the screen becomes the best point, the tuning voltage at that time is stored in the memory. It is judged whether or not all the channels of the updated channel information have been selected (step 423).
After canceling the preset mode (step 424), the tuning operation is ended. If not completed, the operations of (step 412) to (step 423) are repeated.

Next, the configuration will be described according to the channel preset process of the present invention with reference to FIG.

When input to the microcomputer (701) from the input means (702) such as a remote controller or a switch, the normal mode is switched to the channel preset mode. According to the screen displayed by the display unit (703), a position is input by the input unit (702) to specify a location where the tuning voltage data is stored in the memory (711). Next, the band to be searched is switched, and the tuner (7
08), the auto search is performed after switching the band. This is done by the tuner (70) from the microcomputer (701).
The tuning voltage of 8) is searched for using the D / A (Digtal / Analog) converter (710). The determination to stop the search is that there is a sync signal input from the sync signal processing device (705) and the video intermediate frequency signal processing (70
AFT (Aut input to the microcomputer (701) from 6)
omatic Fine Tuninng) Stop the search when the voltage is at the best point. At this time, when the state of the screen is not the best point, the input means (702) notifies the microcomputer (701) to raise and lower the tuning voltage to bring the state of the screen to the best point.

The SAW filter (707) is used for the purpose of stably amplifying only the channel signal to be received and suppressing other unnecessary signals.

Video intermediate frequency signal processing (706) to AG
As C (Automatic Gain Control), the tuner (70
8) is input. FIG. 5 shows a screen display state at the time of channel presetting.

FIG. 2 shows a menu screen when channel information is input, and FIG. 3 shows a screen display during search. Figure 9
Shows a part of the channel information and is an example in which the search range is determined by the channel plan.

[0017]

The relationship between the tuning voltage of the tuner and the time of the conventional voltage synthesizer system and the system of the present invention will be described with reference to FIG.

FIG. 8 shows a relationship between the tuning voltage of the tuner and the time for searching the two points (A and B) of the carrier frequency in a certain band.
In the conventional method, in order to search the two points, the tuning voltage is searched for 0 to the maximum tuning voltage, and T1 time is required. In the system of the present invention, if the tuning voltage for selecting the carrier frequency of a certain station is 805 (center value), the point (801) of −several MHz of the carrier frequency to the center value (805) of + several MHz. Search may be performed between points (802), that is, for T2 time. Similarly, if the point to be tuned to the carrier frequency of another station is 806 (center value), the point of −several MHz (803) to the center value (806) to the point of + several MHz (804) of the carrier frequency. ), That is, T
Search for 2 hours. Therefore, T2 × 2 hours are required to select the two carrier frequencies.

However, the time reduction according to the present invention in the case of FIG. 8 is ΔT = T1− (T2 × 2).

Further, since the band switching is automatically performed based on the channel information as described above, the labor can be saved.

Although the present invention has been described by using TV broadcasting as a model, it goes without saying that it can be generally used for a channel selection system using the voltage synthesizer system.

[Brief description of drawings]

FIG. 1 is a flowchart showing a processing procedure of a channel preset method according to the present invention.

FIG. 2 is a display example of a menu screen at the time of channel presetting according to the present invention.

FIG. 3 is a display example of a screen during a search during channel presetting according to the present invention.

FIG. 4 is a block diagram showing an operation of a channel preset method according to the present invention.

FIG. 5 is an example of a screen when a conventional channel preset is performed.

FIG. 6 is a flowchart showing a processing procedure of a conventional channel preset method.

FIG. 7 is a block diagram showing a configuration of a channel preset system of the related art and the present invention.

FIG. 8 is a diagram showing a relationship between tuner tuning voltage and time.

FIG. 9 is a diagram showing an example in which a search range is determined according to a channel plan.

[Explanation of symbols]

1 Position stored in microcomputer 2 Channel number to select channel 3 Channel number to input when rewriting channel number 4 Currently selected item 5 Determined by channel number VL, VH, U
Indicates 6 Search status

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[Procedure amendment]

[Submission date] December 16, 1993

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Correction target item name] All drawings

[Correction method] Change

[Correction content]

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Claims (1)

[Claims] 1. In a tuning device using a voltage synthesizer method as a tuning method, storage means for storing channel information necessary for performing tuning control,
Display means for displaying a screen in a menu format at the time of channel presetting, input means for a user to input according to the menu screen displayed by the display means, and tuning for controlling the tuning operation according to the channel information called from the storage means. A channel selection device comprising: a control unit.