JPS5914944B2 - Selective operation response device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a remotely controllable television receiver, in which the television receiver itself determines the presence or absence of a remote control signal and indicates by audio output that the remote control signal has been input. The purpose of the circuit is to enable display even when the power is turned on.

FIG. 1 shows a block diagram of a response device that generates a response sound from a television receiver in response to a remote control signal. In the figure a
is a signal from a remote device and is output from the transmitter 1. The signal a enters a receiver 2 on the receiver side, is further amplified by an amplifier 3, and is applied to a signal processing circuit 4. Based on the output of the signal processing circuit 4, power on/off, channel switching, volume adjustment, etc. are performed. On the other hand, the signal from the amplification section 3 is applied to a buffer and waveform conversion circuit 5, converted into a constant width pulse, and applied as a control signal to the oscillation circuit 6. The output of this oscillation circuit 6 is applied to the audio circuit T in parallel with the audio signal b, and is further input to the speaker 8. As a result, when the remote control signal is input, a sound is output from the speaker 8, and it can be confirmed that the remote control signal has been input. 0 In FIG. 1, transmitter 1,
Since the receiving section 2, amplifier 3, signal processing circuit 4, and audio circuit □ are already known, their explanation will be omitted.

FIG. 2 shows a specific embodiment of the buffer/waveform conversion circuit 5 and the oscillation circuit 6. In FIG. 2, resistors 9 and 12 and a transistor 1511 constitute an emitter follower circuit and serve as a buffer circuit. Resistor 10 is transistor 1
1 protection resistor. Resistor 13 and capacitor 14 serve as a noise filter. Resistance 15, 1
6, IT, 19, capacitor 18, transistor 21, 22 constitute a monostable multivibrator circuit. From amplifier 3 comes a control signal from a remote device.

In this example, the pulse is in the positive direction. The control signal from the remote device is a train of 25 coded pulses, the frequency of a single pulse is approximately 500 KHx, and the width of the pulse train is approximately 50 msec. However, the width of the pulse train changes depending on the mode. Therefore, this pulse is used to oscillate a monostable multivibrator and convert it into a constant pulse width. A train of pulses 30 is applied through an emitter follower to the base of one transistor 22 forming a monostable multivibrator. When there is no signal from the remote device, the base of transistor 22 is at a low level, so
The collector of the transistor 21 is at the low 35 level.
When a signal from a remote device is received, it acts as a trigger for the monostable multivibrator, transistor 22 is turned on, transistor 21 is turned off, and the collector of transistor 21 is at a high level. As is well known, the time constant of this monostable multivibrator is 16 resistors and 20 capacitors.
determined by. FIG. 3 shows the waveforms of each part. a is a pulse train, b is a transistor,・E21
is the collector voltage of Here TωZO. 7C2O-
It is determined by Rl6. C2O is the value of capacitor 20, Rl6
is the value of resistor 16. Transistors 29, 30, resistors 23, 24, 25, 26, and capacitors 27, 28 constitute an astable multipipulator.

As is well known, the time constant of the oscillation circuit 6 is T=0.7(C
27R24+C28R25). Here about 3K
Hz. The base of the transistor 30 constituting the astable multivibrator and the monostable multivibrator
A diode 31 is connected to the collector of the transistor 21 constituting the one-chip transistor. When connected in this way, when there is no signal from the remote device, the cathode side of diode 31 is at a low level (VCE8at of transistor 21), so diode 31 is conductive, and the base of transistor 30 is almost grounded (actually is V
D+VCEsat), the astable multivibrator becomes stable, and the collector of transistor 30 becomes high level. On the other hand, in case 2 when the signal from the remote device is present, the cathode side of the diode 31 becomes high level, so the diode 31 becomes non-conductive and starts oscillating as an astable multivibrator. Its oscillation period (FIG. 3c) coincides with the operating period Tω of the monostable multivibrator described at the beginning. 3. An oscillation output signal is applied to the audio circuit 7 from the collector of the transistor 30 constituting the astable multivibrator through the resistor 32 and capacitor 33. It should be noted that the resistor 32 is a three resistor for volume level control, and is selected according to the input impedance of the audio circuit 7 so as to provide an appropriate volume.

(This may be made into a variable resistor so that it can be adjusted.) The capacitor 33 is a capacitor for cutting direct current. In addition, since four differentiating circuits are constructed with the impedance of the next stage, the tone can be changed by selecting the value of this capacitor. Note that it is necessary to select a resistance value for the resistor 32 so that the audio circuit 7 side is not affected. With the above configuration, the presence or absence of a signal from the remote device will be detected and a 3KHz sound will be emitted from the receiver's speaker, allowing the receiver to receive the signal from the remote device without looking at the receiver. It is possible to confirm that the request has been received, and this can be confirmed even if the user is focusing on the remote device and operating it.

By the way, FIG. 2 has the following drawbacks.

When the television receiver is turned off, the audio circuit 7 is turned off for power saving purposes.

In this case, when turning on the power by remote control, the audio power source is slow to start up due to the influence of the load capacitor, so even if the oscillation circuit 6 generates a confirmation sound in response to the remote control signal, it is not in time to confirm when the power is turned on. There is no sound. Furthermore, when the power is turned on, audio is muted for a certain period of time to prevent transient noise from occurring. For the above two reasons, the confirmation sound does not come out when the power is turned on.

The present invention obviates this drawback.

An example of this will be described below with reference to FIG. 4 and a waveform diagram for explaining the operation shown in FIG. 5. The difference between FIG. 4 and FIG. 2 is that a capacitor 39 and a resistor 40 are provided at the output terminal where an output pulse is output when the power of the signal processing circuit 4 is turned on.
While connecting a differential circuit consisting of resistors 42, 43, 4
4, 46, capacitors 45, 47 and transistor 4
A monostable multivibrator consisting of 8 and 49 is made, and the output terminal of the differentiating circuit is connected to the base of the transistor 48 via the diode 41, and the
The collector of the transistor 21 is connected to the base of the transistor 21 constituting another monostable multivibrator through a differentiator circuit consisting of a capacitor 50 and a resistor 51 and a diode.

The rest is the same as in FIG. 2. Next, the operation will be explained.

When the power is turned on by a remote device, the signal processing circuit 4 generates a pulse shown in FIG.

This pulse is applied to a differentiating circuit composed of a capacitor 39 and a resistor 40, and is connected to the cathode side of a diode 41. Furthermore, the anode side of the diode 41 is connected to the transistor 4.
When connected to the base of transistor 48, when the power is turned on, a monostable multivibrator is activated by the negative side pulse of the differential pulse shown in Fig. 5b, and the waveform shown in Fig. 5c is obtained at the collector of transistor 48. . This output signal c is again applied to a differentiating circuit composed of a capacitor 50 and a resistor 51 to obtain the signal shown in FIG. 5d. Among the pulses shown in FIG. 5 d, the monostable multipipulator operates using the negative pulse as a trigger, so that the waveform shown in FIG. 5 e is obtained at the collector of the transistor 21. In other words, for a certain period of time T from when the power is turned on.
A pulse with a pulse width Tw that rises from a point delayed by 8 is obtained. Then, the output of the oscillation circuit 6 is output from the speaker 8 only during this period. The delay time T8 is the transistor 48
, 49, if the time constant of the monostable multi-pipe radar is chosen appropriately, after the sound defeat ends,
And when the audio circuit 8 starts operating, an oscillation sound can be confirmed,
Initial objectives can be achieved. As explained above, according to the present invention, the signal output when the power is turned on is delayed for a certain period of time and added to the oscillation circuit, and by driving the oscillation circuit, it is possible to detect that a remote control signal has been input even when the power is turned on. This is extremely convenient in practice as it allows you to confirm the alarm sound being announced.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a remote control device including a remote control response device of the present invention, FIG. 2 is a specific circuit diagram of a buffer/waveform conversion circuit and an oscillation circuit proposed prior to the present invention, and FIG. 2 is an explanatory diagram of the operation, FIG. 4 is a circuit diagram of a remote control response device in an embodiment of the present invention, and FIG. 5 is an explanatory diagram of the operation of FIG. 4. 1...Oscillating section, 2...Receiving section, 3...
...Amplification section, 4...Signal processing circuit, 5...
...Buffer/waveform conversion circuit, 6...Oscillation circuit, 7...Audio circuit, 39, 40, 50, 5
1... Capacitors and resistors that make up the differential circuit,
41, 52... Diode, 48, 49...
...A transistor that constitutes a monostable multivibrator.

Claims (1)

[Claims] 1 The remote control signal from the remote control device is passed through a waveform conversion circuit, added to the oscillation circuit connected in parallel with the TV audio signal to the audio circuit, and controlled, and the signal output only when the power is turned on is kept constant. A remote operation response device characterized in that by controlling this in addition to the oscillation circuit with a time delay, the response sound to the remote operation can be confirmed even when the power is turned on.