JPH0368566B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION For example, some television receivers are capable of receiving FM signals in addition to television channels. This has become an effective device because the performance of the receiver itself as an audio device has been improved, especially due to audio multiplexing of televisions.

In such a device, if the same channel selection device is used to select both TV and FM, it is convenient for the user and does not make the design too complicated.

That is, FIG. 1 shows an example of such a channel selection device. In the figure, switches S _a1 to _{S so} are respectively switches for channel selection, and these switches S _a1
~ One end of S _ao is the output terminal Q 1 of ring counter ₁ ~
Q _o , the other ends are connected to each other, and the connection point is connected to the IR control terminal. Note that counter 1
Normally, a high potential is output to the output terminals Q ₁ to Q _o , and any one of them is set to the ground potential.

In addition, output terminals Q ₁ to _{Q o} are each connected to a variable resistor V _r1
~ _Vro are connected to the power supply terminal 2, and the sliding contacts of these variable resistors _Vr1 ~ _Vro are connected to each other through opposite diodes D1 _{~ Do} , and the connection points are connected to the TV tuner 3 and Connected to the tuning voltage terminal T of the FM tuner 4.

Furthermore, output terminals Q ₁ ~ _{Q o} are connected to resistors R ₁ ~
It is connected to the movable contacts of the changeover switches S _b1 to S _bo through R _o , and the four fixed contacts L of the switches S _b1 to _{S bo} ,
H, U, and F are connected to each other. The middle point of the connection between the contacts L, the middle point of the connection between the contacts H, and the middle point of the connection between the contacts U are of the TV tuner 3.
Connected to band switching terminals L, H, and U for switching between VHF hard band, high band, and UHF band. Further, the connection midpoint between the contacts F is connected to the control terminal F of the FM tuner 4.

Further, a signal from the remote control signal receiving circuit 5 is supplied to the IR control terminal of the counter 1, the up counting terminal UP, and the down counting terminal DN.
Furthermore, a diode D _x is connected to the switch S _a1 in a direction opposite to the current flowing from the power supply terminal 2 .

In this circuit, when one of the tuning switches S _a1 to _{S ao} is pressed, the IR control terminal of counter 1 becomes high potential, the oscillator (not shown) in counter 1 is driven, and the output of counter 1 is Terminal Q ₁ ~ _{Q o}
are grounded in turn. When the pressed switch and the ground potential output terminal match, the IR control terminal becomes ground potential and the oscillator of the counter 1 is stopped.

Then, the voltage obtained at the sliding contact of the variable resistor _Vri connected to the output terminal _Qi , which is at ground potential, is supplied to the tuners 3 and 4. Also switch S _bi
The ground potential signal obtained from the fixed contact U selected in is supplied to the band switching terminal U of the tuner 3.

In this way, the tuner 3 receives any UHF channel. Similarly, VHF low band, high band, and any FM channel are received and the channel is selected.

Furthermore, when channel selection is performed by remote control, the following procedure is performed.

First, when directly selecting an arbitrary channel, a high potential is first supplied from the receiving circuit 5 to the IR control terminal for a predetermined period, and the output terminal to be selected is
Pulses whose number is one smaller than the order of Q ₁ to Q _o are supplied to the up counting terminal UP.

When the above-mentioned channel selection switches S _a1 to S _ao operate, a high potential is applied to the IR control terminal of the counter 1 from the outputs Q ₁ to _{Q o} , but during remote control, a high potential is applied from the IR control terminal of the receiving circuit 5 to the IR control terminal of the counter 1. Since a high potential is applied to the IR control terminal and a diode D _x is provided, the diode D _x becomes conductive and the counter 1 is temporarily stopped with the output terminal Q ₁ at ground potential. That is, counter 1 is first reset so that the _Q1 output is at a low potential, and then a pulse is applied to the up counting terminal UP to bring the desired output terminal to ground potential. Then, channel selection is performed in the same manner as described above.

Furthermore, when tuning is performed sequentially in the up or down direction, a pulse signal is supplied from the receiving circuit 5 to the up counting terminal UP or the down counting terminal DN of the counter 1 at predetermined time intervals, and the output terminal Q ₁
~Q _o is sequentially brought to the ground potential in the up or down direction. Then, by stopping the receiving circuit 5 at a desired location, channel selection is performed in the same manner as in the top-up mode.

However, in this circuit, when channels are selected sequentially using a remote control, all output terminals Q ₁ to _{Q o} are selected in sequence. In that case, it is fine if the VHF low band, high band, and UHF TV broadcasts are selected in sequence, but if there is FM in the middle, it would be extremely annoying if the screen went off each time. This is especially true in the past because there was a strong belief that TV and FM were two different things, so selecting TV and FM consecutively would give an extremely unnatural feeling.

In view of these points, the present invention sequentially selects only TV channels when the channels are sequentially selected from a state in which TV is being received, and selects only FM channels sequentially when channels are sequentially selected from a state in which FM is being received. This is how it was done. An embodiment of the present invention will be described below with reference to the drawings.

That is, in the present invention, the second
Insert the logic circuit shown in the figure.

In the figure, the IR from the receiving circuit 5 to the counter 1 is
The signal (IR signal) supplied to the control terminal is supplied to the monostable multivibrator 11, and a signal is formed at a time corresponding to the period in which the IR signal rises and the subsequent pulse to the up counting terminal UP is formed. be done. The Q output (high potential during the above-mentioned period) and Q output (low potential during the above-mentioned period) of this vibrator 11 are supplied to AND circuits 12 and 13. Further, a signal (up pulse) supplied to the up counting terminal UP is supplied to AND circuits 12 and 13.

The output of this AND circuit 12 is the OR circuit 14,1
5. Further, a signal from the connection point at the other end of the switches S _a1 to S _ao is supplied to a terminal 16, and a signal from this terminal 16 is supplied to an OR circuit 14.
The output of this OR circuit 14 is supplied to the set terminal S of the SR flip-flop 17.

Also, the output of the AND circuit 13 is the OR circuit 15,1
8. Furthermore, the signal (down pulse) supplied to the down count terminal DN is supplied to the OR circuit 18. The output of this OR circuit 18 is supplied to the reset terminal R of the flip-flop 17.

Furthermore, the output of the OR circuit 18 is supplied to the clock terminal CK of the D flip-flop 19. Further, a signal from the connection point of the fixed contacts F of the switches S _b1 to S _bo is supplied to the terminal 20, and a signal from this terminal 20 is supplied to the input terminal of the flip-flop 19.

The Q output of this flip-flop 19 is supplied to an exclusive OR circuit 21. Also, terminal 2
The signal from 0 is supplied to the OR circuit 221.

Furthermore, the output of the AND circuit 13 is supplied to the set terminal of the flip-flop 22. A down pulse is also supplied to the reset terminal of flip-flop 22.

The Q output of this flip-flop 22 is supplied to an AND circuit 23, and the Q output is supplied to an AND circuit 24. Furthermore, the Q output of flip-flop 17 is supplied to AND circuits 23 and 24. Further, the output of the OR circuit 21 is supplied to AND circuits 23 and 24. Furthermore, the output of the oscillator 25 is output from the AND circuit 2
3,24. It is assumed that the frequency of the oscillator 25 is sufficiently higher than the frequency of the up pulse or down pulse during sequential channel selection.

The output of this AND circuit 23 is supplied to an OR circuit 26. Also, the output of the OR circuit 15 is the output of the OR circuit 2.
6. The output of this OR circuit 26 is supplied to the up counting terminal UP of the counter 1.

Further, the output of the AND circuit 24 is supplied to an OR circuit 27. Further, a down pulse is supplied to the OR circuit 27. The output of this OR circuit 27 is supplied to the down count terminal DN of the counter 1.

Furthermore, the IR signal is supplied to the OR circuit 28.
Further, a signal from the terminal 16 is supplied to an OR circuit 28. The output of this OR circuit 28 is the output of the counter 1.
Supplied to IR control terminal.

In this circuit, when an up pulse or a down pulse is supplied without an IR signal during sequential tuning, these signals are passed through the AND circuit 13, the OR circuits 15 and 26, or the OR circuit 27 to the up counting terminal UP and the down counting terminal DN. supplied to At the same time, these signals are connected to AND circuit 1.
3. The signal is taken out through the OR circuit 18, and the flip-flop 17 is reset by this signal .
The output is brought to a high potential.

Further, a low potential signal is supplied to the terminal 20 when receiving FM, and a high potential signal is supplied when receiving television. This signal is supplied to the D input terminal of flip-flop 19,
By supplying the signal taken out from the OR circuit 18 to the clock terminal CK, a signal for determining whether the channel immediately before switching was FM or TV is output to the Q output terminal. This discrimination signal and the signal from the terminal 20 are supplied to the exclusive OR circuit 21, and when they do not match, a high potential signal is taken out.

Further, when an up pulse is supplied, the Q output of the flip-flop 22 is set to a high potential, and when a down pulse is supplied, the Q output of the flip-flop 22 is set to a high potential.
The output is brought to a high potential.

Therefore, in this circuit, when the FM and TV discrimination signals of the previously selected channel and the next selected channel do not match during sequential tuning, when tuning in the upward direction, the AND circuit 23
When tuning in the down direction, the output of the oscillator 25 is taken out from the AND circuit 24. By supplying this signal to the counter 1 through the OR circuits 26 and 27, the count of the counter 1 rapidly progresses, and the channel where the above-mentioned discrimination signals do not match is not selected (skipped) and proceeds to the next channel. It will be done. When a channel with matching discrimination signals is selected, AND circuits 23 and 24 are shut off.

In addition, when directly selecting a station using the remote control, the IR signal is supplied to the IR terminal through the OR circuit 28, and the subsequent up pulse is supplied to the AND circuit 1.
2. Up counting terminal through OR circuits 15 and 26
Supplied to UP. At the same time, an up pulse is supplied to the flip-flop 17 through the OR circuit 14 to cassette the flip-flop 17. As a result, AND circuits 23 and 24 are cut off.

Therefore, during direct channel selection, even if the discrimination signals do not match, the signal from the oscillator 25 is not extracted.

Furthermore, when selecting a station using switches S _a1 to S _ao , the signal from terminal 16 is passed through OR circuit 28.
Supplied to the IR terminal. At the same time, a signal from terminal 16 is supplied to flip-flop 17 through OR circuit 14, and flip-flop 17 is set. As a result, AND circuits 23 and 24 are cut off.

Therefore, even if the discrimination signals do not match when selecting a channel using the switches S _a1 to S _ao , the signal from the oscillator 25 is not extracted.

In other words, in this circuit, when selecting channels sequentially, if the channel immediately before starting selection is FM, the TV channel is skipped by the output of the oscillator 25, and when the channel immediately before starting selection is TV, the FM channel is skipped and selected. At the same time, when directly selecting a channel, a desired channel is selected regardless of whether it is TV or FM.

The outputs of the logic circuit in each operating state are summarized as shown in FIG.

This is how channel selection is performed, but according to the present invention, if you sequentially select channels when the TV is selected, only the TV will be sequentially selected, and when FM is selected, you will select sequentially. When you tune into a station, only FM channels are selected in sequence, allowing for extremely natural tuning.

Note that the present invention can be applied not only to the two types of TV and FM, but also to the case where the same types of channels of three or more types are sequentially selected.

Furthermore, the same effects can be obtained not only by the above-mentioned discrete logic circuit but also by a microcomputer and software.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an example of a channel selection device, FIG. 2 is a block diagram of an example of the present invention, and FIG. 3 is a diagram for explaining the same. 11 is a monostable multivibrator, 17,1
9 and 22 are flip-flops, and 25 is an oscillator.

Claims (1)

[Claims] 1. In a channel selection device capable of selecting one channel from a plurality of groups each having a plurality of channels, a direct selection means for directly selecting one of the channels, and an up or means for sequentially selecting the channels by a down key operation; and means for detecting a mismatch between the groups to which each channel belongs by comparing the channel switched by the sequential channel selection means with the channel immediately before switching. , means for skipping a channel by outputting an oscillator signal until a mismatch between groups is no longer detected when a mismatch signal is output from the mismatch detection means; and when a mismatch signal is not output from the mismatch detection means; A channel selection device comprising means for selecting a channel.