JPH0683099B2 - Receiver with reception prohibition device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in the following order.

A Industrial field B Outline of the invention C Conventional technology D Problems to be solved by the invention E Means for solving problems (Fig. 1) F Action G Example G ₁ Selection of receiving channel Description G ₂ Description of voice system G ₃ Description of fine tuning G ₄ Description of reception prohibition device H Effect of the invention A Industrial field of application The present invention is a reception prohibition device that can put a desired channel into a reception prohibition state. With receiver.

B Summary of the Invention The present invention is based on the fact that in a receiver with a reception prohibition device that can put a desired channel in a reception prohibition state, the judgment to prohibit reception is made based on an intermediate frequency or a local frequency. The reception prohibition operation is perfected.

C Related Art Conventionally, for example, a television device having a reception prohibition device capable of prohibiting reception of a certain channel has been proposed for educational and other reasons. As an example of such a device, as described in USP4232396, there is a device that prohibits reception by changing a local frequency for tuning of a corresponding channel.

However, according to this example, the setting to the reception prohibited state is
It's just a connection switch. Therefore, it is easy to release the reception prohibited state, and for example, a child may often release the prohibition state without hesitation and watch a program on a channel for which reception is prohibited.

Therefore, when data indicating a channel for which reception is prohibited is stored in a conventional storage device, and when this predetermined channel is selected and received, the data indicating the channel for which this channel is selected and the channel for which reception is prohibited are stored. It is considered that the received data is compared with the represented data, and if they match, the reception prohibited state is set.

D Problems to be Solved by the Invention However, in this case, the following inconvenience may occur.

For example, the ku band from a broadcasting satellite (12 GHz band = 11.7 to 12.
In those capable of receiving satellite broadcast signals of 2 GHz) or c band (4 KHz band = 3.7~4.2GHz), BS (S / U) the first local frequency F _L1 in converter, a first intermediate frequency output from the BS converter F ₁ , the second local frequency F _{L2 in} the BS tuner, and the second intermediate frequency F _{2 in} the BS tuner have a relationship as shown in FIG. 10 for each band.

Here, for example, the user switches the BS converter to the one for the c band, switches the BS tuner to the channel selected state for the c band, and prohibits reception of one channel (3.720 GHz = 3720 MHz), so this one channel is represented. It is assumed that the data is stored in the storage device. The first intermediate frequency F ₁ in this one channel is F ₁ = 5150 MHz (F _L1 ) -3720 MHz = 1430 MHz (1).

Next, the user switches the BS tuner to the ku band tuning state while keeping the BS converter for the c band,
For example, for channels other than 1 channel, 12.180 GHz
And presetting the stations (second local frequency F _L2 = 1832.78MHz). Here, when the preset channel is selected, the station having the first intermediate frequency F ₁ of F ₁ = 1832.78 MHz (F _L2 ) −402.78 MHz (F ₂ ) = 1430 MHz is selected. Since this corresponds to one channel in the c band, it is possible to view the channel for which reception is prohibited.

Further, since there is no channel assignment in the ku band and frequency direct tuning is performed, a method of presetting a station to an arbitrary channel, for example, is adopted as described above. In this case, it is assumed that a 11.700 GHz station is preset on one channel and that one channel is set to the reception prohibited state. But,
In this case, for example, if a station of 11.700 GHz is preset for channel 2 and channel 2 is selected, it is possible to view the station of 11.700 GHz for which reception is prohibited.

In view of such a point, the present invention aims to complete the reception prohibition operation.

E Means for Solving the Problems In order to solve the above-mentioned problems, the present invention is such that the decision to prohibit reception is made based on the frequency associated with the channel. That is, generating means (16) for generating a channel setting signal, and first data representing a frequency associated with a channel selected based on the channel setting signal from the generating means, for example, an intermediate frequency or a local frequency. (17) for creating, a storage means (50) for storing second data representing a frequency associated with a channel for which reception is prohibited, and a channel selection comparing the first data and the second data. And a means (17) for determining whether or not the frequency difference between the frequency associated with the selected channel and the frequency associated with the channel for which reception is prohibited is within a predetermined range. Then, when the frequency difference is within a predetermined range, the signal of the selected channel is not reproduced.

F Action In the above-described configuration, the decision as to whether or not to prohibit reception is not made based on the data representing the channel but is made based on the data representing the frequency associated with the channel. The reproduction of the signal is surely prevented.

G Example An example of the present invention will be described below with reference to FIG. In this example, ku band of 12 GHz band, c of 4 GHz band
This is an example applied to a satellite broadcast receiver that receives a band.

In the figure, the ku band from the broadcasting satellite (10) (12 GHz
Band = 11.7 to 12.2 GHz) or c band (4 GHz band = 3.7 to
The satellite broadcasting signals S _BS of 4.2 GHz are respectively BS antennas (11
k), (11c) through S / U converter (12k), (12c)
Is supplied to. The S / U converter (12k), are (12c) In been frequency conversion, ku band signal S _BS of 950~1450MHz Both c-band '.

That is, the local frequencies for frequency conversion in the S / U converters (12k) and (12c) are 10.75GHz and 5.15GHz, respectively.
Fixed to.

The satellite broadcast signal _SBS has the highest frequency as shown in Fig. 2.
The video signal S _V of 4.2 MHz, FM audio signal above the frequency band of the video signal S _V, which is the carrier for example 5~8.5MHz zone located
It is a signal that S _AFM is multiplexed, and the carrier of 12GHz or 4GHz band is FM-modulated respectively. Therefore, S / U converter (12
The signals S _BS ′ from k) and (12c) are also FM signals.

Here, the audio mode of the satellite signal S _BS is monaural, multiplex, discrete, there is a respective matrix. The FM audio signal S _{AFM in} the monaural mode is a monaural audio signal S _{A in} which a single carrier in the 5-8.5 MHz band is FM-modulated, and its frequency deviation is, for example, 75
It is set to kHz. Also, F in the multiplex mode
The M audio signal S _AFM is a composite signal of the sum signal (L + R) of the left audio signal L and the right audio signal R and the signal in which the subcarrier is FM-modulated by the difference signal (LR), and is a 5-8.5 MHz band signal. Single carrier is FM
It is modulated, and its frequency deviation is, for example, 100 kHz.

Also, FM audio signal S in discrete mode
_AFM uses left audio signal L and right audio signal R for 5 to 8.5MHz
The first and second carriers in the band are FM-modulated, and the frequency deviation thereof is, for example, 75 kHz. In this case, the interval between the first and second carriers is often 0.18 MHz, for example. Further, the FM audio signal S _{AFM in} the case of the matrix mode is the sum signal (L + R) and the difference signal (LR) in which the first and second carrier waves in the 5 to 8.5 MHz band are FM-modulated, and the frequency thereof is The deviation is 100 kHz, for example. In this case, the interval between the first and second carriers is often 1.00 MHz, for example.

The position of the carrier of the FM audio signal S _{AFM in} each mode described above is not fixed uniformly and is arbitrary in the 5.0 to 8.5 MHz band, but the most frequent one is shown in FIG. AD
6.8MHz for mono and multiplex mode, 5.58 for discrete mode as shown in
MHz, 5.76MHz, 5.80MHz in matrix mode,
6.80MHz.

The number of channels in the ku band and the c band is 24, for example.
It is a channel. The polarization plane of the broadcast signal S _BS of each channel is made different between adjacent channels. For example, 1,3,
.., 23 odd-numbered channels are horizontal, and 2, 4, ..., 24 even-numbered channels are vertical. This is because the required bandwidth per channel is, for example, 27 MHz, but the frequency interval of each channel is about 20 MHz, so that interference between adjacent channels is protected.

In addition, in FIG. 1, S / U converters (12k), (12k
The signal S _BS ′ from c) is supplied to the terminal (13) via the changeover switch (1), and the tuner (10) is supplied from this terminal (13).
0) to the signal processing circuit (14). In this signal processing circuit (14), the signal S _BS ′ of 950 to 1450 MHz is, for example, 4
After being converted to an intermediate frequency signal of 02.78MHz, FM demodulation is performed, and the video signal S _V and FM audio signal as shown in FIG.
A composite signal S ₀ with S _AFM is taken out.

In this case, the frequency of the local signal S _L supplied from the PLL circuit (15) for frequency conversion (second local frequency
The reception channel is selected by changing F _L2 ). This PLL circuit (15) is controlled by the operation panel (16)
Based on the operation of the user above, performed by a microcomputer (hereinafter referred to as "microcomputer") (17), PL
This is performed by controlling the frequency division ratio of the frequency divider of the L circuit (15) according to the channel. Further, the signal S _AFT indicating the change of the intermediate frequency F ₂ is supplied from the processing circuit (14) to the microcomputer (17), and the AFT operation is performed so that the intermediate frequency signal is correctly 402.78 MHz.

G ₁ Description of reception channel selection Here, the reception channel is randomly selected with ten keys “1” to “0” on the operation panel (16), and the up key (161) and down key (162 ) Is selected sequentially.

First, the random channel selection will be described. The user presses the number corresponding to the desired channel with ten keys "1" to "0" on the operation panel (16) and finally presses the enter key "ENTE".
When "R" is pressed, the frequency division ratio of the frequency divider of the PLL circuit (15) is changed by the microcomputer (17), and thus the frequency _FL2 of the local signal S _L from the PLL circuit (15) is changed, and The channel is selected.

By the way, as described above, the polarization plane of the broadcast signal S _BS is determined to be horizontal or vertical corresponding to each channel. Therefore, when changing the reception channel, it is necessary to match the reception polarization plane to the reception channel. The key (163) on the operation panel (16) is for switching the reception polarization plane. That is, the state of the switching signal S _PO output from the microcomputer (17) to the terminal (19) via the amplifier (18) and controlling the S / U converters (12k) and (12c) to change the reception polarization plane is The keys (163) are sequentially operated to change the reception polarization plane.

Next, the sequential channel selection will be described. The user selects the up key (161) or down key (16) on the operation panel (16).
When 2) is pressed, the frequency division ratio of the frequency divider of the PLL circuit (15) is sequentially changed by the microcomputer (17). Therefore, the PLL circuit (1
The frequency F _L2 of the local signal S _L from 5) is changed sequentially,
The receiving channels are sequentially switched and selected. In this case, when the up key (161) is pressed, 1 → 3 → ...
→ 23 → 2 → 4 → ・ ・ ・ → 24 → 1 → 3 ... When the receiving channel is selected and the down key (162) is pressed, 23 → 21 → ・ ・ ・ 1 → 24 → 22 → ・ ・ ・ → 2
→ 23 → 21 ... Channels are selected. That is, the odd channel and the even channel are selected alternately. Further, as described above, for example, the polarization planes of the odd channels are horizontal and the polarization planes of the even channels are vertical, so that the reception polarization planes are switched when shifting from the even channels to the odd channels and from the odd channels to the even channels. . That is, at this time, the state of the switching signal S _PO from the microcomputer (17) is changed and the reception polarization plane is switched.

At the time of this channel selection, the display section (201) of the display panel (20) displays the number of selected reception channels. In the example of the figure, it is shown that the channel is in the channel 6 selection state. Further, when the reception polarization plane is switched to horizontal or vertical, the display unit (20) of the display panel (20)
2) or (203) is lit up. Here, the display section (204) of the display panel (20) is lit and displayed when a broadcast is received. Further, the display unit (205) is lit and displayed when the ku band or the c band is received, for example, when the c band is received.

Also, the combined output S output from the signal processing circuit (14)
₀ (see FIG. 2) is supplied to the de-emphasis circuit (21), and the signal pre-emphasized at the transmitting side is returned to the original state. The output of the de-emphasis circuit (21) is supplied to the low-pass filter (22), and the video signal S _V is taken out,
The video signal S _V is amplified by the amplifier (23) and then supplied to the energy diffusion signal removal circuit (24). This elimination circuit (24), the energy spread signal triangular wave superimposed on the video signal S _V is removed at the transmitting end, a video signal S _V muting circuit from the removal circuit (24) and (25) To the output terminal (26). Muting circuit (25)
Is controlled by the control signal S _MV formed from the presence or absence of the carrier of the intermediate frequency 402.78 MHz in the processing circuit (14), and is put into the muting state when there is no carrier of the intermediate frequency 402.78 MHz.

G ₂ Description of audio system In addition, the synthetic output S ₀ output from the processing circuit (14) is supplied to the bandpass filter (30) to extract the FM audio signal S _AFM whose carrier is located in the 5.0 to 8.5 MHz band. Be done. Then, this FM audio signal S _AFM is supplied to PLL circuits (31) and (32) including a mixer and forming a frequency converter. These PLL circuits (31) and (32) are for converting the carrier wave of the FM audio signal S _AFM to 10.7 MHz. In this case, since the single carrier of 5.0 to 8.5 MHz band is used when the audio mode is the monaural mode or the multiplex mode as described above, the conversion output can be obtained from the PLL circuit (31), for example. . On the other hand, in discrete mode or matrix mode, 5.0-
Since the first and second carriers in the 8.5 MHz band are used, the conversion outputs can be obtained from both the PLL circuits (31) and (32).

Here, as described above, the position of the carrier of the FM audio signal S _AFM in each mode is not uniformly determined and is 5.0 to 8.5 MHz.
Optional in the z band. Therefore, in order to receive the desired FM audio signal S _AFM , that is, the carrier of the FM audio signal S _AFM is set to 1
From the microcomputer (17) based on the user's key operation on the operation panel (16) to convert to the intermediate frequency of 0.7MHz
The frequency division ratio control signals S _N1 and S _N2 are supplied to the PLL circuits (31) and (32), respectively, and the frequency division ratios of the frequency dividers of the PLL circuits (31) and (32) are controlled to achieve so-called tuning. Done.

By the way, as described above, the FM audio signal S _{AFM of} each mode
The position of the carrier wave is arbitrary in the 5.0 to 8.5 MHz band, but as shown in FIGS. 3A to 3D, 6.80 MHz in the monaural mode and multiplex mode, and 5.58 MHz and 5.76 MHz in the discrete mode. In addition, in the case of matrix mode, it is often 5.80MHz and 6.80MHz. The key (164) on the operation panel (16) is a key for selecting a voice mode. By sequentially pressing this key (164), the voice mode is changed from monaural → multiplex → discrete → matrix → monaural → ... To be selected. In this case, when switching to monaural mode and multiplex mode, the tuning frequency f in the PLL circuit (31)
It is automatically tuned so that ₁ becomes 6.80MHz.
Also, when switching to discrete mode, the PLL circuit (3
The tuning frequencies f ₁ and f _{2 of} 1) and (32) are 5.58 MHz and
Automatically tuned to 5.76MHz. Furthermore, when switching to matrix mode, the PLL circuit (3
The tuning frequencies f ₁ and f _{2 of} 1) and (32) are 5.80 MHz and
Automatically tuned to 6.80MHz.

When the mode is switched to the monaural mode, the multiplex mode, the discrete mode, or the matrix mode, the display sections (206), (20
7), (208), and (209) are displayed in a luminescent manner.

Further, as described above, in the signal processing circuit (14),
When the receiving channel is switched, the monaural mode is selected as the audio mode, and the tuning frequency f ₁ of the PLL circuit (31) is automatically tuned to be 6.80 MHz.

In this way, the tuning frequency is constant when switching between the modes, but when the position of the carrier of the FM audio signal S _AFM is not at this tuning frequency, the user tunes by operating the keys on the operation panel (16). To be done. Here, the tuning is performed using the numeric keys "1" to "0" or the up key (161) and the down key (162) after pressing the voice tuning key (165) on the operation panel (16). Hereinafter, the case of the discrete mode will be described as an example.

When the voice tuning key (165) is pressed, the display section (210) of the display panel (20) lights up, indicating that the voice tuning is being performed, and the display section (201) is shown in FIG. 4A. The display is as shown. In the figure,
“1” indicates that it is the tuning frequency f ₁ in the PLL circuit (31), and “5.58” indicates the value of the tuning frequency f ₁ . Next, the key-in with the ten keys “1” to “0” or the up key (161) and the down key (162) are pressed to receive the FM audio signal S _AFM of the first carrier wave whose tuning frequency f ₁ is the discrete mode. Is set. And, in the display part (201) of the display panel (20),
The newly set tuning frequency f ₁ as shown in FIG. 4B
Is displayed.

In this case, when tuning by pressing the up key (161) and the down key (162), for example, 10kH
It is done in z steps. Then, based on the presence or absence of the carrier of the intermediate frequency, the sweep speed is increased when there is no carrier, and the sweep speed is decreased when there is a carrier.

By the way, as described above, in the discrete mode, the interval between the first and second carriers is statistically 0.18 MHz in many cases. Therefore, when tuning the tuning frequency f _1, the tuning frequency f ₂ in the PLL circuit (32) is f ₁
It is automatically set to + 0.18MHz. That is, when f ₁ is set to 5.30 MHz as shown in FIG. 4B, f ₂ = 5.30 + 0.18 =
It is set to 5.48MHz. When the FM audio signal S _AFM of the second carrier in the discrete mode is received at this tuning frequency f ₂ , this completes the tuning.

On the other hand, when the FM audio signal S _AFM of the second carrier in the discrete mode cannot be received at the tuning frequency f ₂ , the audio tuning key (165) is pressed again. At this time, the display as shown in FIG. 4C is displayed on the display section (201) of the display panel (20). In the figure,
“2” indicates that it is the tuning frequency f ₂ in the PLL circuit (32), and “5.48” indicates that value. Next, by pressing the key-in with the ten keys “1” to “0” or pressing the up key (161) and the down key (162), the tuning frequency f ₂ becomes
Set to receive FM audio signal S _AFM . Also in this case, when tuning is performed by pressing the up key (161) and the down key (162), for example, the tuning is performed in steps of 10 kHz, and when there is no carrier of the intermediate frequency, the sweep speed is increased and the carrier is At certain times the sweep speed is slowed. The tuning frequency f ₂ is tuned independently.

The above description has been made by taking the case of the discrete mode as an example, but the same applies to the case of the matrix mode. In this case, when tuning the tuning frequency f ₁ , the tuning frequency is
f ₂ is automatically set to f ₂ +1.00 MHz.

Further, in the case of the monaural mode and the multiplex mode, it is sufficient to tune only the tuning frequency f ₁ .

In Fig. 1, the carrier wave obtained from the PLL circuit (31) is 1
The 0.7 MHz audio signal S _A1 is a narrowband bandpass filter (3
3) and a wide band pass filter (34) to supply to the fixed terminals on the A side and B side of the changeover switch (35), respectively. In addition, the carrier wave obtained from the PLL circuit (32) is 10.7M.
The audio signal S _{A2 of} Hz is supplied to the fixed terminals on the A side and the B side of the changeover switch (38) via the narrow band pass filter (36) and the wide band band pass filter (37), respectively.
When the audio mode is the monaural mode or the discrete mode, since the frequency deviation is relatively narrow at 75 kHz as described above, the changeover switches (35) and (38) are changed over to the A side, and the changeover switches (35) and ( From 38), the audio signals S _A1 and S _A2 that have passed through the narrow band pass filters (33) and (36) are obtained. On the other hand, when the audio mode is the multiplex mode or the matrix mode, the frequency deviation is relatively wide as 100 kHz as described above, so that the wide band bandpass filters (34) and (37) are output from the changeover switches (35) and (38). ), The audio signals S _A1 and S _A2 that have passed through

The changeover switches (35) and (38) are changed over as follows. That is, the microcomputer (17) generates a 2-bit signal [A, B] corresponding to the selection of the voice mode. That is, [1,1] is generated in the monaural mode, [0,0] is generated in the multiplex mode, [1,0] is generated in the discrete mode, and [0,1] is generated in the matrix mode.

Thus, the signal A is "1" in the monaural mode and the discrete mode and "0" in the multiplex mode and the matrix mode, and the signal A is supplied to the changeover switches (35) and (38) as the changeover signal. It When the signal A is "1", it is switched to the A side, and when it is "0", it is switched to the B side.

The audio signals S _A1 and S _A2 extracted from the change-over switches (35) and (38) are supplied to the FM demodulators (39) and (40), respectively. The demodulated outputs from the FM demodulators (39) and (40) are supplied to the audio processing circuit (41).

The audio processing circuit (41) performs processing according to each audio mode. That is, the 2-bit signal [A, B] from the microcomputer (17) is supplied to the decoder (42), and this decoder (4
In 2), it is converted into a 4-bit signal [a, b, c, d] and supplied to the audio processing circuit (41) as a control signal. For example, [1,1] in monaural mode is [1,0,0,0], [0,0] in multiplex mode is [0,1,0,0], and [1,0] in the case is converted to [0,0,1,0], and [0,1] in the matrix mode is converted to [0,0,0,1]. As a result, the audio processing circuit (41) is controlled, and processing according to each audio mode is performed.

In the monaural mode, the first circuit of the processing circuit (41)
And a monaural audio signal is taken out from the second output, and amplifiers (43) and (44) and a muting circuit (45) are taken out, respectively.
And (46) and output terminals (47) and (48). In the case of the multiplex mode, the discrete mode, and the matrix mode, the left audio signal L and the right audio signal R are extracted from the first and second outputs of the processing circuit (41), and the amplifiers (43) and (44) are respectively extracted. ), Through the muting circuits (45) and (46), the output terminal (4
It is output to 7) and (48).

In addition, the audio signals S from the FM demodulators (39) and (40), respectively.
_The signals S _M1 and S _M2, which have a low level “0” when _A1 and S _A2 are present and a high level “1” when they are not present, are output to the AND circuit (49), respectively. The muting circuits (45) and (46) are operated when the output of the AND circuit (49) is at a high level "1", that is, when there is no audio signal S _A1 or S _A2 .

Also, the signals S _M1 and S _M2 from the FM demodulators (39) and (40)
Is supplied to the microcomputer (17) and is used for sweep speed control at the time of tuning the audio signal by the up key (161) or the down key (162) as described above.

G ₃ Explanation of fine tuning The key (166) on the operation panel (16) is for fine tuning. That is, it is to prevent beat interference due to interference between the broadcast signal (SHF wave) from the broadcasting satellite and the ground communication signal (SHF wave), and is used for selecting the receiving channel in the signal processing circuit (14). The center frequency of tuning is slightly shifted.

When the fine tuning key (166) is pressed,
The display section (201) of the display panel (20) displays as shown in FIG. 5A. In the figure, "00.0" indicates that the center frequency of tuning has not shifted. Then use the up key (161) or down key (16
2) When is pressed, the center frequency of tuning is
It is shifted in 0.2MHz steps. In this case, display (20
In 1), the shifted frequencies are displayed as shown in FIG. 5B. This shift amount is set to such a degree that the disturbance becomes less noticeable than the screen, for example, and is set to about +10 MHz at maximum.
This is because if you move it too much, the screen will become distorted. At this time, the AFT operation is prohibited so that the shifted frequency does not return to the original. When the reception channel is switched, the prohibition of this AFT operation is released. The AFT operation is started at power-on. In FIG. 6, when f ₁ is the interference frequency and f _J is the original center frequency of tuning,
For example, the center frequency is forcedly shifted like f _F.

G ₄ Explanation of reception prohibition device In the example of FIG. Reception of a predetermined channel can be prohibited. That is, while a predetermined channel is selected (the display unit (201) is shown in FIG. 7A), the key (parent key) (16) of the operation panel (16)
When 7) is pressed, a display is made on the display unit (201) as shown in FIG. 7B. Next, enter the 3-digit index signal ID with the ten keys "1" to "0" and the display (20
In 1), the display is made as shown in FIG. 7C. next,
When the enter key “ENTER” is pressed, if the input index signal ID matches the index signal ID ₀ corresponding to the predetermined channel previously stored in the non-volatile memory (50), the display section (201) displays The display as shown in FIG. 7D is made, and this predetermined channel, in the illustrated example, channel 6 is set in the reception prohibited state.

To the reception disabled state, changed the dividing ratio of the PLL circuit (15) being changed frequency F _L2 of the local signal S _L, so that the center frequency tuning is the band for example 1480MHz of 950~1450MHz band To be When the reception is disabled, the muting circuit (25) operates in the signal processing circuit (14) because the carrier wave of 402.78MHz is lost, and the FM demodulation circuit (39) also operates.
Since the signals S _M1 and S _M2 from the signals (40) and (40) are both at the high level “1”, the muting circuits (45) and (46) operate to enter the voice muting state.

Further, in this case, the microcomputer (17) has the S / U converter (12k) corresponding to the channel for which reception is prohibited,
Data representing the carrier frequency of the signal S _BS ′ from (12c), that is, the first intermediate frequency F ₁₁ is created, and this is written in the nonvolatile memory (50) as the data DA ₁ .

On the other hand, if the index signal ID does not match ID ₀ ,
The original display is made on the display unit (201) as shown in FIG. 7E, and reception of a predetermined channel is not prohibited.

In addition, a key (167) of the operation panel (16) is pressed while a predetermined channel is selected and the reception is prohibited for this channel (the display unit (201) is shown in FIG. 8A). Then, a display is made on the display unit (201) as shown in FIG. 8B. Next, use the numeric keypad "1" to "0" to enter 3
Input the digit index signal ID and display (201)
Is displayed as shown in FIG. 8C. Next, when the enter key “ENTER” is pressed, if the input index signal ID matches the index signal ID ₀ corresponding to the predetermined channel stored in advance in the non-volatile memory (50), then FIG. Is displayed, and the reception prohibited state of this predetermined channel, in the illustrated example, channel 6 is released. When the reception prohibited state is released, the center frequency of tuning is returned to the correct position, so
The operations of the muting circuits (25), (45) and (46) are also stopped and the muting state is released. Further, in this case, the data DA _{1 of} the non-volatile memory (50) is cleared. On the other hand, when the index signal ID does not match ID ₀ , the original display is made on the display unit (201) as shown in FIG. 8E, and the reception prohibited state of the predetermined channel is not released.

Also, the user can use the numeric keypad “1” on the operation panel (16)
When you press the number corresponding to the desired channel with "0" and finally press the enter key "ENTER", the microcomputer (17) will display the first intermediate frequency F corresponding to this desired channel.
Data DA ₂ representing ₁₂ is created.

Then, this data DA ₂ is compared with the data DA ₁ (usually a plurality of DA ₁ a, DA ₁ b ...) Of the non-volatile memory (50),
The first intermediate frequency F ₁₁ corresponding to the data _{DA 1 (F 11 a, F} 11 b, ·
..) and the first intermediate frequency F ₁₂ corresponding to the channel selected by the user are within a predetermined range, the signal of the channel selected by the user is not reproduced. . On the other hand, when the frequency difference is outside the predetermined range, the signal of the channel selected by the user is reproduced. The frequency difference within the predetermined range is, for example, the pull-in range of the AFT.

When the data DA ₁ is cleared, the frequency difference is always outside the predetermined range, and the signal of the channel selected by the user is reproduced.

The flowchart of FIG. 9 shows the above operation.

That is, when the key (167) of the operation panel (16) is pressed in the state of selecting a predetermined reception channel, the display (2
“P” is displayed in 01), and the reception is prohibited and the prohibition is released. Next, when the index signal ID is input with ten keys “1” to “0” and the enter key “ENTER” is pressed, the input index signal ID is stored in the nonvolatile memory (50) in advance. signal
It is determined whether or not it matches with ID ₀ . If they do not match, the display on the display unit (201) is returned to the original state and the key sense state is set. If they match, it is determined whether or not the reception is prohibited. If the reception is not prohibited,
The operation is determined to be the reception prohibited state, and the reception prohibited state is set. Then, data representing the first intermediate frequency F ₁₁ corresponding to the channel currently selected is created, and this is created as the data DA ₁ in the non-volatile memory (50).
Written in. Then, the tuning frequency is out of the band, "PL" is displayed on the display unit (201), and the key sense is set. If the reception is prohibited, it is determined that the operation is for canceling the reception, and the reception prohibited state is canceled. And non-volatile memory (50)
Data DA _{1 of} is cleared. Then, the center frequency of tuning is returned to the original position so that the predetermined channel can be received, "PL" on the display unit (201) is erased, and the key sense is restored.

Also, the user can use the numeric keypad “1” on the operation panel (16)
When the number corresponding to the channel to be selected is input with "0" and the enter key "ENTER" is pressed next, the data DA ₂ representing the first intermediate frequency F ₁₂ of this channel to be selected is selected. Is created. Then, this data DA ₂ is compared with the data DA ₁ (DA ₁ a, DA ₁ b, ...) Written in the non-volatile memory (50), and the data DA ₁ (DA ₁ a, DA ₁ Frequency difference between the first intermediate frequency F ₁₁ (F ₁₁ a, F ₁₁ b, ...) corresponding to b, ...) And the first intermediate frequency F ₁₂ corresponding to the channel selected by the user. | F ₁₁ (F ₁₁ a, F ₁₁ b, ...) − F ₁₂ | is determined whether it is within a predetermined range, for example, within 10 MHz. When this frequency difference is outside the predetermined range, the center frequency of tuning is set to be able to receive the selected channel,
The signal of this selected channel is reproduced. on the other hand,
When the frequency difference is within the predetermined range, the tuning frequency is out of the band, and the signal of the selected channel is prevented from being reproduced.

The key (168) on the operation panel (16) is for the output terminal (2
This is a key to use the signals output to 6), (47), and (48) as external input signals. External input terminals, change-over switches, etc. are not shown in FIG. 1 for a simple description of the drawing. Further, for example, when switching to the external input side, the display section (211) of the display panel (20) is lit and displayed.

As described above, according to this example, the determination as to whether or not the reception is prohibited is not made based on the data representing the frequency associated with the channel, but the first corresponding to the channel.
Since it is performed based on the data DA ₁ representing the intermediate frequency F ₁₁ , it is possible to reliably prevent the reproduction of the signal of the channel for which reception is prohibited.

In the above-mentioned embodiment, the first intermediate frequency is used as the frequency associated with the channel.
As is clear from FIG. 10, the broadcast frequency, the second local frequency _FL2, etc. can also be used.

In this example, the out-of-band tuning is performed, but muting may be performed or no channel selection operation may be performed at all.

H According to the present invention described above, the determination as to whether or not reception is prohibited is not made based on the data representing the channel but is made based on the data representing the frequency associated with the channel. Therefore, it is possible to reliably prevent the reproduction of the signal of the channel for which reception is prohibited.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIGS.
FIG. 10 is a diagram for explaining it, and FIG. 10 is a diagram for explaining a conventional example. (14) is a signal processing circuit, (15) is a PLL circuit, (16) is an operation panel, (17) is a microcomputer, (50) is a non-volatile memory, and (100) is a tuner.

Claims (1)

[Claims] 1. A receiver capable of putting a desired channel into a reception prohibited state, wherein a generating means for generating a channel setting signal and a channel selected based on the channel setting signal from the generating means are provided. Creating means for creating first data representing a related frequency, storage means for storing second data representing a frequency associated with a channel for which reception is prohibited, the first data and the second data. And a determining means for determining whether or not a frequency difference between the frequency associated with the selected channel and the frequency associated with the channel for which reception is prohibited is within a predetermined range. A receiver with a reception inhibiting device, wherein the signal of the selected channel is not reproduced when is within the predetermined range.