JP2001016524A - Automatic presetting device of channel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic presetting device of a channel capable of automatically omitting an unnecessary channel after automatically presetting the channel. SOLUTION: A channel is automatically seeked and preset to a memory by tuning in steps S11 to S14. The automatically preset channel is successively scanned again to tune in a step 15. The presence/absence of a synchronizing signal in each tunned channel is decided in a step S16. A channel decided to have no synchronizing signal is deleted from the memory in a step S17.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic channel presetting apparatus for automatically searching for and presetting a broadcast channel such as a television broadcast.

[0002]

2. Description of the Related Art FIG. 3 is a flowchart for explaining the operation of a conventional automatic channel presetting device.
In FIG. 3, when the process of the automatic preset is started,
For example, the search is performed from the lowest frequency in the receivable range, and the channel is selected in step S1. In step S2, it is determined whether or not there is a synchronization signal, and if so, the frequency is stored in a memory,
If not, the process returns to step S1. By performing the above operation from the lowest frequency to the highest frequency of the receivable range, in step S4, channel selection in the entire receivable range ends.

In the case of multi-channels as in Europe, it takes a considerable amount of time to automatically preset channels, so that the presence / absence of a synchronizing signal in step S2 is determined so as to search the entire receivable range as quickly as possible. In a short time. Therefore, an unnecessary channel (a channel that is not a legitimate signal) may be preset by mistake. Therefore, in step S5, the user manually deletes unnecessary channels one by one, and the process of the automatic preset ends.

[0004]

As described above, in the conventional automatic channel presetting device, a complicated operation of manually deleting unnecessary channels has to be performed, which is a burden on the user. Was.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above problems, and has as its object to provide an automatic channel presetting apparatus capable of automatically deleting unnecessary channels after automatically presetting channels.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems of the prior art, the present invention relates to an automatic channel presetting device for automatically searching for channels and presetting them in a memory. Tuning means for sequentially tuning (step S15) and determining means for determining the presence or absence of a synchronization signal in each channel tuned by the tuning means (step S1)
6) and a deletion unit (step S17) for deleting from the memory the channel determined to have no synchronization signal by the determination unit. .

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an automatic channel presetting device according to the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a block diagram showing an embodiment of the automatic channel presetting device of the present invention, and FIG. 2 is a flowchart for explaining the operation of the automatic channel presetting device of the present invention.

In this embodiment, a configuration in which an automatic channel presetting device is used for a television receiver will be described.
In FIG. 1, a television broadcast wave input from an antenna 1 is received by a tuner 2. Tuner 2
Generates an intermediate frequency (IF) signal and inputs it to the IF circuit 3. The IF circuit 3 extracts a video signal and an audio engagement from the IF signal. Here, illustration of the processing of the audio signal is omitted. The video signal is a video chroma circuit 4
The video chroma circuit 4 inputs the RGB signals to the cathode ray tube 9.

The synchronization signal detection circuit 5 detects whether or not the output of the IF circuit 3 contains a synchronization signal. The DC voltage from the IF circuit 3 is input to an AFC (automatic frequency control) circuit 6, and the AFC circuit 6 determines whether the DC voltage is within a predetermined range, and thereby tunes the tuner 2 correctly. Is detected. Synchronous signal detection circuit 5
Is input to the microprocessor 7. The output of the AFC circuit 6 is also input to the microprocessor 7. If the tuning in the tuner 2 is off, the AFC circuit 6 detects it, and the microprocessor 7 adjusts the tuning frequency in the tuner 2. As a result, the tuner 2 can correctly tune to each channel.

When an automatic preset of a channel described later is performed, the frequency of the preset channel is stored in the memory 8. Once you preset the channel,
If you receive that preset channel,
The microprocessor 7 controls the tuner 2 by reading the frequency from the memory 8. Therefore, in this case, AF
It is not necessary to operate the C circuit 6.

Here, the operation of the automatic channel presetting device according to the present invention will be described. In FIG. 2, when the automatic preset process is started, for example, a search is performed from the lowest frequency in the receivable range, and a channel is selected in step S11. In step S12, the microprocessor 7 determines whether or not there is a synchronizing signal based on the output of the synchronizing signal detecting circuit 5. If so, the frequency is stored in the memory 8, and if not, the process returns to step S11. By performing the above operation from the lowest frequency to the highest frequency of the receivable range, in step S14, channel selection in the entire receivable range ends.

Further, in step S15, all the channels preset in the memory 8 are sequentially scanned (tuned) again, and in step S16, it is determined whether or not there is a synchronization signal. The determination of the presence or absence of the synchronization signal in step S16 takes longer than the determination of the presence or absence of the synchronization signal in step S12, and the presence or absence of the synchronization signal is carefully determined. At this time, as described above, the AFC circuit 6
You can tune preset channels directly without using.

If it is determined in step S16 that there is a synchronization signal, the process returns to step S15. Step S16
If it is determined that there is no synchronization signal, step S17
Then, the channel is deleted from the memory 8 and the step S is performed again.
Return to 15. The above operation is performed for all preset channels, and the automatic preset processing is completed.

As described above, the user does not need to manually delete unnecessary channels one by one, and can automatically delete unnecessary channels. If the determination of the presence or absence of the synchronization signal in the conventional step S2 of FIG. 3 is performed for a long time, it is possible to prevent a problem that an unnecessary channel is erroneously preset.
Automatic presetting of channels can take a considerable amount of time. On the other hand, in the present invention, after the automatic presetting, only the preset channel needs to be directly tuned without using the AFC circuit 6 to determine the presence / absence of the synchronization signal, so that a long time is not required. Also, time and man-hours can be significantly reduced as compared with a case where unnecessary channels are manually deleted.

[0015]

As described in detail above, the automatic channel presetting device of the present invention comprises a tuning means for sequentially tuning the channels after the automatic presetting, and the presence / absence of a synchronization signal on each channel tuned by the tuning means. And a deletion unit for deleting from the memory a channel determined to have no synchronization signal by the determination unit. Therefore, unnecessary channels are automatically deleted after the channels are automatically preset. be able to. Therefore, the user does not need to perform complicated work, and the burden on the user can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a flowchart for explaining the operation of the present invention.

FIG. 3 is a flowchart for explaining the operation of the conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Antenna 2 Tuner 3 IF circuit 4 Video chroma circuit 5 Synchronous signal detection circuit 6 AFC circuit 7 Microprocessor 8 Memory 9 Cathode ray tube

Claims (1)

[Claims] 1. A channel automatic presetting device for automatically searching for a channel and presetting it in a memory, comprising: tuning means for sequentially tuning the channels after automatic presetting again; and synchronizing signals for the respective channels tuned by the tuning means. An automatic channel presetting device comprising: a determination unit for determining presence / absence; and a deletion unit for deleting, from the memory, a channel determined to have no synchronization signal by the determination unit.