JP2003283939A - Television broadcast receiver having broadcast automatic detecting function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect and register all receivable broadcasts in a television broadcast receiver having an automatic broadcast detecting function without repetitively registering the same broadcast. <P>SOLUTION: When a broadcast detection step is executed (#8) to detect a television broadcast with an AFT voltage set to 1/2H (YES in #9), a step of registering a receiving frequency at this time in a memory 7 is executed (#10) to set a broadcast detection flag (#11). While the broadcast detection flag is set (YES in #2), the broadcast detection step is not executed until the AFT voltage becomes enough higher than 1/2H (NO in #4). When the AFT voltage becomes enough higher than 1/2H (YES in #4), the broadcast detection flag is cleared (#7) to resume the broadcast detection step (#8-#11). <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television broadcast receiver having a broadcast automatic detection (channel preset) function of detecting a broadcast transmission frequency and pre-registering it.

[0002]

2. Description of the Related Art Conventionally, in a receiving device for receiving a broadcast, when signals of a plurality of channels are periodically received, information obtained by shortening the receiving period and reducing variations in the receiving period. There is known a receiving device that suppresses the loss of data.
0-276385). Further, when the AGC voltage is higher than a predetermined value, the AFT (Auto Fine Turning) voltage is shifted to a lower value, so that the receiving device is provided with a tuning circuit that can surely perform the tuning operation even when the antenna input is a weak electric field. Is known (for example, Japanese Patent Laid-Open No. 6-
(See Japanese Patent No. 152333). In addition, a receiver is provided with a detection circuit for detecting that the PLL circuit is in an unlocked state, and the AFT voltage is defined based on the output signal of the detection circuit so that the tuning state of one channel can be accurately determined. Are known (for example, Japanese Patent Laid-Open No. 10-3276).
No. 8).

By the way, in Europe and the like, television broadcasting is transmitted in different frequency bands in each country. In such a broadcast receiving device for a wide area, since it is complicated to preset the receiving frequency for each country at the time of factory shipment, after the device is installed in the user's home, etc. A broadcast receiving device having a broadcast automatic detection function of automatically detecting and registering a broadcast transmission frequency is suitable.

In the broadcast receiving apparatus having the automatic broadcast detection function, the presence or absence of the broadcast is judged by increasing the reception frequency of the tuner by a predetermined value and detecting the AFT voltage at that time. It has been known. In such a device, the AFT voltage becomes 1/2 the reference value when the difference between the broadcast signal transmission frequency and the tuner reception frequency is the smallest.
The frequency at which the FT voltage becomes 1/2 the reference value is detected, and that frequency is stored in the memory as the broadcast transmission frequency.

When the tuner reception frequency is gradually increased, as is well known, the AFT voltage takes a maximum value slightly lower than the above reference value at frequencies other than the broadcast signal transmission frequency, and the broadcast signal transmission is performed. It starts to drop near the frequency, passes through a half of the reference value at the transmission frequency, and then drops to near 0 [V]. After that, after taking a certain minimum value, it rises sharply and returns to the original value (maximum value). A frequency range in which the AFT voltage goes down to a value 1/2 times the reference value and then rises again to become higher than the value 1/2 the reference value, that is, AFT
The frequency range in which the voltage is lower than 1/2 times the reference value depends on the broadcasting station, but usually depends on the performance of the tuner. For example, when a certain tuner is used, it is about 1 MHz.
In the range, the AFT voltage becomes lower than the value which is 1/2 times the reference value.

[Problems to be Solved by the Invention]

[0006] In such a television broadcast receiving apparatus that detects the broadcast signal by detecting the AFT voltage while changing the reception frequency of the tuner, the reception frequency of the tuner is set so as to quickly detect the broadcast signal. , Are required to be changed at some distance, for example,
It is designed to be able to raise by about 0.3MHz. However, as described above, the AFT voltage is half the reference value.
The range of the frequency lower than the doubled value is about 1 MHz, which is wider than the step of changing the reception frequency, so even though the reception frequency of the tuner is increased to search for the next broadcast,
The disadvantage that the same broadcast is repeatedly detected occurs.

Therefore, when the frequency at which the AFT voltage becomes 1/2 the reference value is detected, the reception frequency of the tuner is shifted by several MHz so that the same broadcast is repeatedly detected and not registered. A device with countermeasures may be considered. However, the frequency range in which the above-mentioned AFT voltage is lower than a value that is ½ times the reference value is different for each broadcasting station, and may last 1 MHz or more depending on the broadcasting station. Further, it does not necessarily mean that another broadcast station is not broadcasting within the range of the shifted frequency of several MHz. Therefore, it is not possible to determine how much the reception frequency of the tuner should be shifted. If the tuner reception frequency is shifted by about 5 MHz, and another broadcast station broadcasts within this frequency range, the broadcast cannot be detected.

The present invention has been made in order to solve the above-mentioned problems, and a television capable of detecting and registering all receivable broadcasts while not repeatedly registering the same broadcast. It is an object to provide a John broadcasting receiver.

[0009]

In order to achieve the above object, the invention of claim 1 receives an analog broadcast signal of a television broadcast and, at the same time, receives an analog AFT (Auto Fine Fine).
Turning) receiving means for outputting a voltage signal, first AD converting means for converting an analog broadcast signal received by the receiving means into a digital signal, and an analog AFT voltage signal output by the receiving means for digital AFT voltage signal Second A / D conversion means for converting into a digital AFT voltage signal converted by the second A / D conversion means and a first A
Frequency detection means for detecting the transmission frequency of the television broadcast based on the synchronization signal included in the digital signal converted by the D conversion means, and storage means for storing the transmission frequency of the television broadcast detected by the frequency detection means. And a frequency adjusting means for outputting a command for adjusting the receiving frequency of the receiving means, the frequency adjusting means predetermines the receiving frequency of the receiving means from the lower limit frequency that the receiving means can receive to the upper limit frequency. The digital AFT voltage signal of the reference value 1
In a television broadcast receiving apparatus having a broadcast automatic detection function of detecting a frequency that becomes a value of / 2 and registering the frequency in the storage means as the transmission frequency of the television broadcast, the frequency detection means has the transmission frequency of the television broadcast. Flag registering means for setting a broadcast detection flag indicating that a broadcast has been detected, and determining means for determining whether or not the broadcast detection flag is set when the reception frequency of the receiving means is increased or decreased. When the determination means determines that the broadcast detection flag is set, the operation limit means for limiting the frequency detection operation of the frequency detection means or the frequency storage operation of the storage means and the voltage level of the digital AFT voltage signal are set. When the voltage level of the AFT voltage signal is detected and becomes sufficiently higher than half the reference value, it is stored in the storage means. Comprising an operation limit canceling means for canceling the limitation of the operation of the frequency detecting means or memory means to clear the feeding detection flag, the frequency detecting means or storage means, AF
Avoid shifting the frequency until the voltage level of the T voltage signal becomes sufficiently higher than half the reference value and then restarting the broadcast detection processing or registration processing so that the same broadcast transmission frequency is not registered multiple times. It was done.

In this structure, when the receiving means adjusts the receiving frequency and receives the broadcast signal transmitted from a certain broadcasting station, the operation is restricted while continuously receiving the broadcasting signal of the broadcasting station. The means limits the operation of the frequency detection means or the storage means so that the transmission frequency of the same broadcast is not registered a plurality of times. The operation limiting means limits the above operation based on the broadcast detection flag. The broadcast detection flag is set by the flag giving means after detecting the television broadcast having the frequency detecting means and registering the station in the storing means.

The set broadcast detection flag indicates that the AF
It is cleared by the operation restriction releasing means which detects that the voltage level of the T voltage signal has become sufficiently higher than the value of 1/2 times the reference value. By clearing the broadcast detection flag, the above operation restriction is released, and the reception frequency is shifted until the voltage level of the AFT voltage signal becomes sufficiently higher than the value of 1/2 times the reference value, and then the detection processing of the next broadcast is performed. Alternatively, the registration process is restarted by the frequency detection means or the storage means. By repeating the above operation from the lower limit frequency that the receiving unit can receive to the upper limit frequency, all broadcasts that the receiving unit can receive are detected. The above AFT
The voltage level at which the voltage level of the voltage signal is sufficiently higher than half the reference value is sufficient for the receiving frequency of the receiving means to deviate from the frequency band of the same broadcast at the next detection of the AFT voltage signal. Voltage level.

Further, the invention of claim 2 receives an analog broadcast signal of a television broadcast, and at the same time, the analog A
A receiving unit that outputs an FT (Auto Fine Turning) voltage signal, a first AD converting unit that converts the analog broadcast signal received by this receiving unit into a digital signal, and an analog AFT voltage signal that the receiving unit outputs are digital. AFT
Based on the second AD converting means for converting into a voltage signal, the digital AFT voltage signal converted by the second AD converting means and the synchronizing signal included in the digital signal converted by the first AD converting means. A frequency detecting means for detecting a transmitting frequency of the television broadcast, a storing means for storing the transmitting frequency of the television broadcast detected by the frequency detecting means, and a frequency adjusting means for outputting a command for adjusting the receiving frequency of the receiving means. The frequency adjusting means increases or decreases the reception frequency of the receiving means by a predetermined value from the lower limit frequency that the receiving means can receive to the upper limit frequency, and the frequency detecting means uses the digital AFT voltage signal. A broadcast station that detects a frequency that is 1/2 times the reference value and registers the frequency in the storage means as the transmission frequency of the television broadcast. In a television broadcast receiver having a detection function, the frequency detecting means detects a frequency that is 1/2 times the reference value, stores the frequency in the storing means, and then converts it by the second AD converting means. AFT
An operation limit that detects the voltage level of the voltage signal and limits the frequency detection operation of the frequency detection means or the frequency storage operation of the storage means until the voltage level of the AFT voltage signal becomes sufficiently higher than a value 1/2 times the reference value. The frequency detection means or the storage means restarts the broadcast detection processing or registration processing after shifting the frequency until the voltage level of the AFT voltage signal becomes sufficiently higher than a value of 1/2 times the reference value, The transmission frequency of the same broadcast is not registered multiple times.

In this configuration, when the receiving means adjusts the reception frequency and receives the broadcast signal transmitted from a certain broadcasting station, the operation is restricted while continuously receiving the broadcasting signal of the broadcasting station. The means limits the operation of the frequency detection means or the storage means so that the transmission frequency of the same broadcast is not registered a plurality of times. The operation limiting means continues the above operation limitation until it detects that the voltage level of the AFT voltage signal has become sufficiently higher than a value that is 1/2 times the reference value. In this way, the reception frequency is shifted until the voltage level of the AFT voltage signal becomes sufficiently higher than the value of 1/2 the reference value, and then the frequency detection means or the storage means restarts the broadcast detection processing or the registration processing, and the reception means. All broadcasts that can be received are registered. The voltage level at which the voltage level of the AFT voltage signal is sufficiently higher than a value 1/2 times the reference value is
It is a voltage level sufficient for the receiving frequency of the receiving means to deviate from the frequency band of the same broadcast at the next detection of the AFT voltage signal.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION (Embodiment 1) A hard disk recorder equipped with a television broadcast receiving apparatus according to an embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 shows a block diagram of a hard disk recorder. The hard disk recorder 1 is a video / audio recording device that compresses and converts input video / audio signals into digital data compliant with the MPEG standard and records the digital data on the hard disk 9. The hard disk recorder 1 has an antenna 3a.
A television broadcast receiving device 2 that receives an analog television broadcast signal via the TV, converts it to a digital video / audio signal, and outputs it, and a digital video / audio signal output from the television broadcast receiving device 2. An MPEG encoder 8 that compresses according to the MPEG standard and a hard disk 9 that records MPEG data compressed by the MPEG encoder 8 are provided. Further, the hard disk recorder 1 is an MP that reads MPEG data recorded on the hard disk 9 and decodes it into digital video / audio signals.
It also includes an EG decoder 10 and a video encoder 11 that converts the digital video / audio signals decoded by the MPEG decoder 10 into analog video / audio signals and outputs the analog video / audio signals to the TV monitor device 20.

The television broadcast receiver 2 has an automatic broadcast detection (channel preset) function of detecting a broadcast transmission frequency and pre-registering it so that channel selection can be performed quickly and easily. The detection of the broadcast transmission frequency in the television broadcast receiving apparatus 2 is performed by detecting the AFT voltage signal. The AFT voltage signal is originally a signal detected when adjusting a slight deviation between the transmission frequency and the reception frequency of television broadcasting. In the television broadcasting receiver 2, the AFT voltage is 1 when the difference between the transmission frequency and the reception frequency is the smallest, which is the reference value.
By utilizing the fact that the value becomes 1/2, the television broadcast is detected by detecting the frequency at which the AFT voltage becomes 1/2 the reference value.

The television broadcast receiving apparatus 2 receives a television broadcast signal transmitted as an analog signal and outputs a tuner (reception means) 3 for outputting an analog AFT voltage signal, and an analog received by the tuner 3. Video encoder (first AD conversion means) 4 for converting the broadcast signal of the above into a digital video / audio signal, and a tuner 3
The analog AFT voltage signal output by the
An AD converter (second AD conversion means) 5 for converting into a T voltage signal, and a microcomputer (frequency detection means, frequency adjustment means, flag giving means, determination means, operation limiting means, operation) which controls each part of the hard disk recorder 1. Restriction releasing means) 6, the operation program of the microcomputer 6, and the microcomputer 6
And a nonvolatile memory (storing means) 7 for storing the transmission frequency of the broadcast detected by.

During the automatic broadcast detection processing, the microcomputer 6
Sets a tuner frequency in which the frequency is increased or decreased by a predetermined value from the lower limit frequency that the tuner 3 can receive to the upper limit frequency, and outputs a command to the tuner 3 to adjust the reception frequency. The tuner 3 receiving this command tunes to the above tuner frequency, and the analog AFT
The voltage signal is output to the AD converter 5. The AD converter 5 converts the analog AFT voltage signal output from the tuner 3 into a digital signal so that the microcomputer 6 can detect it. The microcomputer 6 detects the digital AFT signal converted by the AD converter 5, and detects the broadcast based on it.

FIG. 2 shows the relationship between the reception frequency received by the tuner 3 and the AFT voltage signal output from the tuner 3. In FIG. 2, the band A is a frequency band in which the reception frequency of the tuner 3 deviates from the band of the transmission frequency of the broadcast and the AFT voltage has a value (maximum value) slightly lower than the reference value H, and the frequency B is 1 where the AFT voltage decreases. In the frequency band having a value of / 2H, in the band C, the frequency band in which the AFT voltage further decreases to approximately 0 [V] and below the value of 1 / 2H, and in the frequency D, the AFT voltage sharply increases and then 1 / Each of the frequencies is sufficiently higher than the value of 2H. If the reception frequency of the tuner 3 becomes higher than the frequency D, A
The FT voltage returns to the original value slightly lower than the reference value H. In addition,
The voltage level at which the voltage level of the AFT voltage signal is sufficiently higher than the value of 1 / 2H is a voltage level sufficient for the reception frequency of the tuner 3 to deviate from the frequency band of the same broadcast at the next detection of the AFT voltage signal. Say.

In the present television broadcast receiving apparatus 2, the voltage level of the AFT voltage signal is detected while increasing the reception frequency of the tuner by about 0.3 MHz when detecting the broadcast. Here, if the voltage level becomes smaller than the value of 1 / 2H, the reception frequency is returned by about 0.3 MHz, and then the reception frequency is increased in a finer step.
An accurate frequency at which the FT voltage has a value of 1 / 2H is detected. As a result, the broadcast transmission frequency can be accurately detected.

The relationship between the reception frequency and the AFT voltage shown in FIG. 2 can be seen not only in television broadcasting but also in FM broadcasting and the like. Therefore, in a broadcast receiving apparatus used in a wide area such as Europe where the frequency band used for transmitting television broadcast and FM broadcast differs from country to country, the broadcast signal of the television and the FM signal are transmitted.
It is necessary to distinguish and detect the broadcast signals of the above so as not to confuse them. Therefore, in the present television broadcast receiving apparatus 2, the television broadcast detection processing by the microcomputer 6 is
In addition to the AFT voltage signal, a sync signal peculiar to television broadcasting included in the digital signal converted by the video encoder 4 is used.

The microcomputer 6 controls the tuner 3 in the band A.
When the frequency f of the television broadcast in which the AFT voltage takes a value of 1 / 2H is detected while outputting the command for adjusting the reception frequency, the memory 7 registers it as the broadcast transmission frequency. Further, the microcomputer 6 has an AFT voltage of 1 / 2H.
In band C having a smaller value, it is determined that the broadcast signal of the same broadcast station is continuously received, and the duplicate broadcast detection process and registration process are limited. After that, when the microcomputer 6 detects that the AFT voltage has a value sufficiently higher than 1 / 2H at the frequency D, it determines that the reception frequency of the tuner 3 will soon deviate from the frequency band of the same broadcast, and registers it in the memory 7. The processing restriction is released and the next broadcast detection processing or registration processing is restarted.

The restriction of the duplicate broadcast detection processing and the registration processing by the microcomputer 6 and the cancellation thereof are processed based on the presence or absence of the broadcast detection flag indicating the state in which the television broadcast is detected. The broadcast detection flag is set after detecting a television broadcast in which the voltage level of the AFT voltage is 1 / 2H and registering the station in the storage means, and the voltage level of the AFT voltage signal is 1/2 times the reference value. Cleared when it is detected that the value is sufficiently higher than the value. This allows
After the tuner 3 detects a certain television broadcast, the broadcast detection flag is set while the broadcast signal of the same broadcast station is continuously received, and the duplicate broadcast detection process and the registration process are performed. Is limited.

The operation of the microcomputer 6 when the television broadcast receiving apparatus 2 detects a broadcast will be described with reference to FIG. The microcomputer 6 that received the instruction for automatic broadcast detection
The frequency of the tuner 3 is set (# 1), and a command for adjusting the reception frequency is output to the tuner 3. If the broadcast detection flag is not set, the microcomputer 6 (# 2
In NO, the AFT voltage is detected, and the broadcast detection process is executed (# 8). By this broadcast detection processing, AFT
If the television broadcast having the voltage of 1 / 2H is not detected (NO in # 9), the process proceeds to # 5. After that, if it is not the frequency at which the broadcast detection is completed (the upper limit value of the frequency that the tuner 3 can receive) (NO in # 5), the frequency is increased by 0.3 MHz (# 6), and the process returns to # 1. The operation of the microcomputer 6 in the band A is shown by the above processing loop. Also, by the broadcast detection processing of # 8, the AFT
If a television broadcast with a voltage of 1 / 2H is detected (YES in # 9), a process of registering the reception frequency at that time as the frequency f of the television broadcast in the memory 7 is executed (# 10) to detect the broadcast. After setting the flag (# 11), the process proceeds to # 5. The operation of the microcomputer 6 at the frequency B is shown by a loop including the above processing.

On the other hand, if the broadcast detection flag is set in # 2, the AFT voltage is confirmed (# 3) and this A
If the FT voltage is not sufficiently higher than 1 / 2H (NO in # 4), the process proceeds to # 5. Microcomputer 6 in band C
The operation of is shown by the loop including the above processing. If the AFT voltage is sufficiently higher than 1 / 2H (YES in # 4), after clearing the broadcast detection flag (#
7), and shifts to # 5. The operation of the microcomputer 6 at the frequency D is shown by a loop including the above processing.
The above process is repeated until the reception frequency of the tuner 3 reaches the frequency at which the broadcast detection ends, and when the frequency reaches the broadcast detection end (YES in # 5), the process ends.

As described above, in the present television broadcast receiving apparatus 2, the microcomputer 6 detects that the voltage level of the AFT voltage signal becomes smaller than the value of 1 / 2H, and then 1 /
The memory 7 is used until it becomes sufficiently higher than the value of 2H.
The same broadcast is not registered a plurality of times because the overlapping registration process is restricted. Furthermore, the microcomputer 6
Since the registration process to the memory 7 which has been restricted when the voltage level of the AFT voltage signal becomes high enough to determine that the frequency of the tuner 3 will soon deviate from the frequency band of the same broadcast, the detection process of the next broadcast or The registration process is restarted, and all broadcasts that the tuner 3 can receive can be detected without omission.

The present invention is not limited to the configuration of the above embodiment, and various modifications can be made. For example, the television broadcast receiving device is not limited to the form incorporated in the hard disk recorder, and the television is not limited thereto. It may be built in a receiver or a video cassette recorder. Further, the received broadcast signal is not limited to analog television broadcast, and may be digital television broadcast. In this case, the video encoder and A
The D converter may be omitted. Further, the broadcast signal is not limited to television broadcast, but can be widely applied to FM broadcast and the like.

[0027]

As described above, according to the invention of claim 1,
Until the voltage level of the AFT voltage signal becomes sufficiently higher than the value of 1/2 the reference value, the operation limiting means limits the operation of the frequency detecting means or the storing means, so that the same broadcast is not registered a plurality of times. . Moreover, when the voltage level of the AFT voltage signal becomes sufficiently higher than the value which is 1/2 times the reference value, the operation restriction releasing means releases the operation restriction of the frequency detecting means or the storing means, so that detection or registration of the next broadcast is resumed. Therefore, all the broadcasts that the receiving means can receive can be detected without omission, and the automatic detection of the broadcasts can be properly performed.

According to the second aspect of the invention, the operation limiting means limits the operation of the frequency detecting means or the storing means until the voltage level of the AFT voltage signal becomes sufficiently higher than a value which is 1/2 times the reference value. , The same broadcast will not be registered multiple times. Moreover, after the reception frequency is shifted until the voltage level of the AFT voltage signal becomes sufficiently higher than the value 1/2 times the reference value, detection or registration of the next broadcast by the frequency detection means or the storage means is restarted. All broadcasts that can be received by the receiving means can be registered without omission, and automatic detection of broadcasts can be properly performed.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a hard disk recorder including a television broadcast receiving apparatus according to an embodiment of the present invention.

FIG. 2 shows a reception frequency received by the tuner of the device,
The figure which showed the relationship of the AFT voltage signal output from the same tuner.

FIG. 3 is a flowchart showing an operation of a microcomputer included in the apparatus when a broadcast is detected.

[Explanation of symbols]

2 Television Broadcast Reception Device 3 Tuner (Reception Means) 4 Video Encoder (First AD Conversion Means) 5 AD Converter (Second AD Conversion Means) 6 Microcomputer (Frequency Detection Means, Frequency Adjustment Means, Flag Adding Means, Determination Means, operation restriction means, operation restriction release means) 7 Memory (storage means)

Claims (2)

[Claims] 1. An analog AFT (Auto Fine Turnin) while receiving an analog broadcast signal of a television broadcast.
g) a receiving means for outputting a voltage signal and a first means for converting an analog broadcast signal received by the receiving means into a digital signal
AD conversion means, second A / D conversion means for converting the analog AFT voltage signal output from the reception means into a digital AFT voltage signal, and digital AFT voltage signal converted by the second AD conversion means. And frequency detection means for detecting the transmission frequency of the television broadcast based on the synchronizing signal included in the digital signal converted by the first AD conversion means, and the transmission frequency of the television broadcast detected by the frequency detection means. And a frequency adjusting means for outputting a command for adjusting the reception frequency of the receiving means, wherein the frequency adjusting means extends from a lower limit frequency that the receiving means can receive to an upper limit frequency. Until the receiving frequency of the receiving means is increased or decreased by a predetermined value, the frequency detecting means controls the digital A
A television broadcast receiving apparatus having a broadcast automatic detection function of detecting a frequency at which an FT voltage signal has a value that is 1/2 times a reference value and registering the frequency in the storage means as a transmission frequency of a television broadcast, After the frequency detection means registers the transmission frequency of the television broadcast in the storage means, a flag giving means for setting a broadcast detection flag indicating that a broadcast has been detected, and when the reception frequency of the reception means is increased or decreased, Determining means for determining whether or not the broadcast detection flag is set, and when the determining means determines that the broadcast detection flag is set, the frequency detection operation of the frequency detection means or the frequency storage operation of the storage means is performed. An operation limiting means for limiting, detecting a voltage level of the digital AFT voltage signal,
When the voltage level of the AFT voltage signal becomes sufficiently higher than a value that is 1/2 times the reference value, the broadcast detection flag stored in the storage means is cleared and the operation of each operation of the frequency detection means or the storage means is cleared. The frequency detection means or the storage means shifts the frequency until the voltage level of the AFT voltage signal is sufficiently higher than the half of the reference value, and then detects the broadcast. A television broadcast receiving apparatus having a broadcast automatic detection function, characterized in that the processing or registration processing is restarted so that the transmission frequency of the same broadcast is not registered a plurality of times. 2. An analog AFT (Auto Fine Turnin) while receiving an analog broadcast signal of a television broadcast.
g) a receiving means for outputting a voltage signal and a first means for converting an analog broadcast signal received by the receiving means into a digital signal
AD conversion means, second A / D conversion means for converting the analog AFT voltage signal output from the reception means into a digital AFT voltage signal, and digital AFT voltage signal converted by the second AD conversion means. And frequency detection means for detecting the transmission frequency of the television broadcast based on the synchronizing signal included in the digital signal converted by the first AD conversion means, and the transmission frequency of the television broadcast detected by the frequency detection means. And a frequency adjusting means for outputting a command for adjusting the reception frequency of the receiving means, wherein the frequency adjusting means extends from a lower limit frequency that the receiving means can receive to an upper limit frequency. Until the receiving frequency of the receiving means is increased or decreased by a predetermined value, the frequency detecting means controls the digital A
A television broadcast receiving apparatus having a broadcast automatic detection function of detecting a frequency at which an FT voltage signal has a value that is 1/2 times a reference value and registering the frequency in the storage means as a transmission frequency of a television broadcast, The frequency detection means detects a frequency that is ½ times the reference value, stores the frequency in the storage means, and then the AFT converted by the second AD conversion means.
The voltage level of the voltage signal is detected, and the frequency detection operation of the frequency detection means or the frequency storage operation of the storage means is limited until the voltage level of the AFT voltage signal becomes sufficiently higher than a value that is 1/2 times the reference value. The frequency detection means or the storage means shifts the frequency until the voltage level of the AFT voltage signal becomes sufficiently higher than a value of 1/2 the reference value, and then detects or registers the broadcast. A television broadcast receiving apparatus having a broadcast automatic detection function, characterized in that the processing is restarted so that the same broadcast transmission frequency is not registered a plurality of times.