JP2556399B2 - Remote control amplifier and its control device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for remotely controlling state changing means such as a variable attenuator included in an amplifier from a remote location, and more particularly to a device for controlling a plurality of state changing means. .

[0002]

2. Description of the Related Art Conventionally, as a device for remotely controlling an amplifier from a remote position as described above, when a television broadcast signal received by an antenna provided outdoors is amplified by an amplifier provided on a column or the like of the antenna. Some control the gain of this amplifier indoors at a distance. An example of such a device is shown in, for example, Japanese Utility Model Publication No. 58-52740. As shown in FIG. 10, the positive half wave of the AC voltage generated on the secondary side of the power transformer 2 is taken out by the diode 4 and the level thereof is adjusted by the variable resistor 6 to be the gain adjustment voltage. The operating voltage composed of the negative half-wave of the AC voltage extracted by the diode 8 is combined at the connection point 10, and the high frequency blocking coil 12 and the transmission line 1 are combined.
4 to the variable gain amplifier 16 side. The negative half-wave of the transmitted AC voltage is rectified and smoothed by the rectifying / smoothing circuit including the high-frequency blocking coil 18, the diode 20, and the capacitor 22, and the power supply terminal 2 of the variable gain amplifier 16 is supplied.
3 is supplied. On the other hand, the positive half-wave whose level is adjusted is rectified and smoothed by the rectifying / smoothing circuit including the diode 24 and the capacitor 26 from the high frequency blocking coil 18, and is supplied to the gain control voltage input terminal 28. Therefore, the gain of the variable gain amplifier 16 is adjusted to the gain according to the value adjusted by the variable resistor 6.

[0003]

However, the above-mentioned device can only adjust the gain of one variable gain amplifier. As shown in Japanese Patent Publication No. 61-54292, even if the positive half-wave and the negative half-wave of the AC voltage are used as the gain adjusting voltages, only the gains of two amplifiers can be adjusted. Can not. The television broadcast signal has a UHF band and a VHF band, and moreover, V
The HF band is divided into a low channel and a high channel. Therefore, when amplifiers are provided in these three bands and the gains of these three bands are to be controlled from remote locations, the above-mentioned device cannot be implemented. In addition, when controlling the gains of a plurality of amplifiers all to be the same, the above device can be used, but in the case of an amplifier for amplifying different bands as described above, it is necessary for each amplifier. Since the gains to be obtained are often different from each other, they cannot be practically used in the above-mentioned device. Further, in the device as described above,
AC power is supplied to the variable gain amplifier, and there is a problem that it cannot be used when DC power is supplied.

According to the present invention, the signal states of a plurality of, especially three or more state changing means can be controlled individually from distant positions, and the amplifier having the state changing means has a DC power source and an AC power source. It is an object of the present invention to provide a remote control amplifier and its control device which can be used regardless of the type of power supply.

[0005]

In order to achieve the above object, the remote control amplifier of the present invention has a plurality of state changing means for changing the state of the signal according to the level of the state adjusting signal, as the amplifying means. It is provided. This amplification means can change the state
The output signal of the means is output to the transmission line. The amplification means include
Extraction means is provided for receiving a superimposed signal obtained by superimposing the modulation control signal and the output of the operating power source for the amplification means from the transmission line and extracting the modulation control signal from the superimposed signal. The modulation control signal is the output signal of the amplification means and
Each has a different fundamental frequency from the operating power output.
Separately, the state variable means, which is frequency-shifted in the non-overlapping range,
An output signal of the amplification means, which is a composite signal of the same number of control signals.
Also, the carrier wave whose frequency is different from the operating power output is modulated
It is. Further, the remote control amplifier according to the present invention includes demodulation means for demodulating the extracted modulated control signal into the composite signal, and demultiplexing the demodulated composite signal into the control signals, and then performing frequency shift. It also has demultiplexing conversion means for converting the status adjustment signal having a corresponding level and supplying it to the corresponding status changing means. Further, the control device according to the present invention is provided at a position apart from the amplification means.
Then, the operating power output generating means for generating an operating power supply output to said amplifying means, and a control signal generating means for generating said control signal, and modulates the transport <br/> wave synthesis signals of the respective control signal A modulation control signal generation means for generating a modulation control signal and a superposition means for superposing the modulation control signal on the output of the operating power source so as to be transmitted to the amplification means are provided.

[0006]

According to the present invention, the operation power supply output generating means
The operating power output is supplied to the amplifying means via the transmission line. Further, the modulation control signal generated by the control signal generation means, in which the carrier wave is modulated by the combined signal of the respective control signals whose frequency is shifted from the fundamental frequency, is supplied to the amplification means side via the line. Each modulation control signal is demodulated by the demodulation means into a combined control signal. The combined control signal is demultiplexed by the demultiplexing conversion means, converted into a state adjustment signal having a level corresponding to the frequency shift, and supplied to the corresponding state changing means. The carrier wave and the control signal are output signals of the amplification means.
And because it has a different frequency than the operating power output,
Interference with the output signal of the amplification means and the output of the operating power supply
Absent. In addition, each control signal is
Since the frequency is shifted from the wave number, each state can be changed.
The state of the signal at the means according to the frequency deviation of each control signal
It can be finely adjusted individually and acts as a variable adjustment of each amplification means.

[0007]

EXAMPLE A first example is shown in FIGS. In this embodiment, as shown in FIG. 1, a so-called booster 30 and
The power source and control device 32, and the booster 30
Is for amplifying a VHF band television broadcast signal and a UHF band television broadcast signal received by an antenna (not shown). The VHF band television broadcast signal input from the input terminal 34 is The wave 36 separates the low-channel television broadcast signal VL and the high-channel television broadcast signal VH. The low-channel television broadcast signal VL is amplified by the low-channel amplifier 44 including the state changing means 42 between the pre-stage amplifying section 38 and the post-stage amplifying section 40. Similarly, the high-channel television broadcast signal VH is transmitted to the front-stage amplifier 46.
Is amplified by a high-channel amplifier 52 having a state changing means 50 between it and the latter-stage amplifier 48. The low-channel television broadcast signal VL thus amplified
And the high channel television broadcast signal VH are mixed by the mixer 54. Further, the UHF band television broadcast signal input from the input terminal 56 is amplified by a UHF amplifier 68 including a bandpass filter 58, a front stage amplification section 60, a state changing means 62, a middle stage amplification section 64, and a rear stage amplification section 66. To be done. This amplified UHF band television broadcast signal is mixed by the mixer 70.
It is mixed with the VHF band television broadcasting signal from 4.
It is supplied to the output terminal 74 via the capacitor 72 of the superposition circuit 71, and is supplied to the power supply and control device 32 via the line, for example, the coaxial cable 76.

As the state changing means 42, 50, 62,
For example, a variable attenuator 78 as shown in FIG. 2 can be used. This variable attenuator 78 includes a PIN diode 8
0, the cathode side of which is grounded through a resistor 82, and the anode side of which is supplied with a DC voltage through a resistor 84, and the DC voltage is changed to change the PIN voltage.
By changing the high frequency resistance value of the diode 80, the attenuation amount of the high frequency signal flowing from the cathode side to the anode side of the PIN diode 80 is changed. Reference numeral 86 is a bypass capacitor, and a DC voltage for controlling the amount of attenuation is supplied from a demultiplexing converter 88 described later.

Returning again to FIG. 1, the UHF band and VHF band television broadcast signals supplied from the booster 30 to the power supply and control device 32 via the coaxial cable 76 are supplied from the terminal 90 to the superposition circuit 92. It is supplied to the terminal 96 via the capacitor 94 of the circuit 92. Since this terminal 96 is connected to, for example, a television receiver, the UHF band and VH amplified by the booster 30 are used.
An F band television broadcast signal is supplied to the television receiver.

The power supply and control device 32 has a transformer 98 for transforming a commercial AC voltage. The AC voltage induced on the secondary side of the transformer 98 is rectified by a rectifying circuit 100 and further with a capacitor 102. The smoothing circuit 106 including the high frequency choke 104 converts the voltage into a DC voltage, and the high frequency blocking coil 110, which is the primary coil of the mutual induction coupling circuit 108 of the superposition circuit 92, the terminal 90, and the coaxial cable 76.
Is supplied to the output terminal 74 of the booster 30 via.

The power supply and control device 32 has a control unit 112, which has fundamental oscillation frequencies of, for example, 4.75 KHz (f1) and 38 KHz (f).
2) and 304 KHz (f3), and eight frequency oscillating circuits 114, 116 and 118, which have the same frequency relationship with 304KHz (f3) and the same number as the state changing means 42, 50 and 62. As shown in FIG. 3, the variable frequency oscillating circuit 114 includes three inverters 120, 122, 124, a resistor 126, a variable resistor 128, and a capacitor 130, and a resistor 126, a variable resistor 128. The value of the capacitor 130 is selected so that the fundamental oscillation frequency is 4.75 KHz, and the frequency is shifted by changing the resistance value of the variable resistor 128.
The width Δf1 of this frequency shift is set to ± 2 KHz, for example. This frequency shift oscillation signal, that is, the control signal is output through the low pass filter 132 in order to prevent generation of unnecessary harmonics.

Since the variable frequency oscillating circuits 116 and 118 have the same structure, detailed description thereof will be omitted, but the fundamental oscillating frequencies are 38 KHz and 304 KHz, respectively, and the frequency deviation widths Δf2 and Δf3 are ± 16 KHz, respectively.
Variable frequency oscillating circuit 1 at ± 150 KHz
Different from 14. Then, the frequency variable oscillation circuit 116,
The control signal from 118 is also low-pass filter 134, 1
It is output via 36 . These low pass filters 1
The control signals that have passed through 32, 134 and 136 pass through capacitors 138, 140 and 142 and attenuators 144 and 1 respectively.
46, 148 to adjust the level of each control signal and then combine by combining the output signals of the attenuators 144, 146, 148.

This combined control signal is applied to the modulator 1 shown in FIG.
It is supplied to 50 amplitude modulation circuits 152. As shown in FIG. 3, the amplitude modulation circuit 152 has an amplification circuit 154 that amplifies the combined control signal. The amplification circuit 154 includes a transistor 156, and the amplified output of the amplification circuit 154 is the amplitude modulation transistor 158. Supplied to the emitter. Further, the amplitude modulation circuit 152 has a crystal oscillation circuit 160, and the crystal oscillation circuit 160 includes a crystal oscillator 162,
An oscillating transistor 164, and oscillates a carrier having a frequency (f0) lower than that of the television broadcast signal at a frequency that does not affect the VHF band television broadcast signal and the UHF band television broadcast signal, A carrier wave is supplied to the base of the modulation transistor 158. Therefore, from the collector of the amplitude modulation transistor 158,
A modulation control signal obtained by amplitude-modulating the carrier wave with the composite control signal is obtained. The state of this modulation control signal is shown in FIG. Since the carrier wave is amplitude-modulated by the frequency-shifted control signal,
Depending on the frequency deviation on both sides of the carrier wave (f0), sidebands within the range of f0 ± f1 ± Δf1, f0 ± f2 ± Δ, respectively
Sidebands within the range of f2 and sidebands within the range of f0 ± f3 ± Δf3 are generated, and this modulation control signal is supplied to the unbalanced attenuation circuit 170 via the capacitor 166 and the bandpass filter 168. To be done. Bandpass filter 1
68 is for preventing leakage of unnecessary harmonics.

The modulation control signal from the unbalanced attenuator circuit 170 is reciprocally coupled to the high frequency blocking coil 110 on the primary side of the mutual inductive coupling circuit 108.
2 is supplied. Therefore, the direct current voltage from the smoothing circuit 106 to which the modulation control signal is mutually induced is supplied to the terminal 90, and from there, is supplied to the output terminal 74 of the booster 30 via the coaxial cable 76. That is, booster 30
A signal obtained by superimposing a modulation control signal on a DC voltage is transmitted from the power supply and control device 32 through the coaxial cable 76. The unbalanced damping circuit 1 selected for the asymmetrical constant
Reference numeral 70 is for attenuating the level of the modulation control signal. The level is attenuated when the modulation control signal is a high frequency blocking coil 110 on the primary side of the mutual inductive coupling circuit 108.
This is to balance the DC output of the smoothing circuit 106 so as to favorably perform mutual inductive coupling and to remove harmonics of the modulation control signal.

The superposed signal transmitted through the coaxial cable 76 is demodulated in the booster 30 via the high frequency blocking coil 172 of the superposing circuit 71 in the demodulator 17 as shown in FIG.
4 is supplied. The DC voltage of the superimposed signal is separated by the high frequency blocking coil 176 as shown in FIG. 5, and the smoothing circuit 18 including the resistor 178 and the capacitor 180 is separated.
1 is further smoothed by each amplifier unit 3 shown in FIG.
8, 40, 46, 48, 60, 64, 66 and band amplification circuits 194, 196, 198 are supplied as operating DC voltage.

As shown in FIG. 5, the modulation control signal of the superimposed signal is separated from the superimposed signal by the capacitor 182 and the bandpass filter 184, that is, extracted, and the demodulator including the diode 186, the capacitor 188, and the resistor 190. It is demodulated into a combined control signal by 192.
Then, the demodulated combined control signal is sent to the demultiplexing converter 8
8 is supplied. The demultiplexing converter 88 includes the band amplification circuit 19
4, 196, 198, and the band amplification circuit 194 is 2
Two transistors 200, 202 and two resonant circuits 2
04 and 206, and these resonance circuits 204 and 206
As shown in FIG. 6, the resonance frequency is selected to be slightly higher than the highest frequency of the frequency deviation Δf1 of the control signal whose fundamental frequency is 4.75 KHz. Therefore, when the control signal having the fundamental frequency of 4.75 KHz is demultiplexed and the control signal is shifted to the highest frequency of the frequency deviation Δf1, the highest level output is generated, and also to the lowest frequency. When offset, it produces the lowest level output. This output is taken from the emitter of the transistor 202, and the diode 20
8. A rectifying / smoothing circuit 212 including a capacitor 210 is rectified and smoothed, and is supplied to the state changing means 42 as a DC voltage for attenuation amount control, that is, a state adjustment signal.

Similarly, the band amplification circuit 196 demultiplexes the control signal having a fundamental frequency of 38 KHz, and an output of a level corresponding to the frequency deviation is obtained. This output is rectified and smoothed by the rectification smoothing circuit 214, and the state is obtained. The variable means 50 is supplied as a DC voltage for controlling the amount of attenuation. Further, the band amplifying circuit 198 demultiplexes the control signal having a fundamental frequency of 304 KHz, and an output having a level corresponding to the frequency deviation thereof is obtained. This output is rectified and smoothed by the rectifying and smoothing circuit 216, and the state changing means 62. Is supplied as a DC voltage for attenuation control. In addition, each band amplification circuit 194, 19
The operating voltage to 6 and 198 is supplied from the smoothing circuit 181.

Since the control signal having a fundamental frequency of 4.75 KHz is frequency-shifted by the frequency variable oscillation circuit 114, a DC voltage having a level corresponding to the frequency shift is obtained from the rectifying / smoothing circuit 212, and this is the state. Since it is supplied to the variable means 42, the amount of attenuation of the state variable means 42, and hence the gain of the VHF band low channel amplifier 44, corresponds to the frequency deviation of the frequency variable oscillation circuit 114, and similarly the state variable means 50. Of the VHF band high channel amplifier 52, and thus the gain of the VHF band high channel amplifier 52, corresponds to the frequency deviation of the control signal whose fundamental frequency in the frequency variable oscillation circuit 116 is 38 KHz. The gain of the UHF amplifier 68 is 30 when the fundamental frequency in the frequency variable oscillation circuit 118 is 30.
It corresponds to the frequency deviation of the control signal of 4 KHz.
In this way, in this embodiment, even if three amplifiers are provided, the gain of each amplifier can be adjusted individually.

FIG. 7 shows a second embodiment. In the first embodiment, the carrier wave is amplitude-modulated by the composite control signal, but in the second embodiment, the carrier wave is frequency-modulated by the composite control signal. Therefore, in the power supply and control device 32a, each frequency variable oscillation circuit 114, 116, 11 of the control unit 112 is provided.
The respective control signals from 8 are combined to form the frequency modulation circuit 15
2a, the carrier wave is frequency-modulated by the combined control signal to generate a modulation control signal. This modulation control signal is supplied to the booster 30a as in the first embodiment. In the booster 30a, the modulation control signal is the capacitor 1
82, extracted from the superimposed signal by the bandpass filter 184, limited in amplitude by the amplitude limiter 218, demodulated by the frequency discriminator 192a, and then transmitted to the band amplification circuits 194, 196, 198 of the demultiplexing converter 88. After being supplied, the same processing as in the first embodiment is performed thereafter.
The reason why frequency modulation is used is as follows. The length of the coaxial cable 76 between the booster 30a and the power supply and control device 32a is shorter than expected, the attenuation in the coaxial cable 76 is small, and even if the attenuation amount of each state changing means is increased, the terminal 90 In some cases, the level of each television broadcast signal supplied to the device may be higher than expected. In such a case, an attenuator is inserted between the booster 30a and the power supply and control device 32a. Alternatively, a distributor may be inserted between the coaxial cable 76 and the terminal 90 of the power supply and control device 32a to distribute the output of the booster 30a to other television receivers. In such a case, the level of the modulation control signal transmitted to the booster 30a side also decreases, and when the modulation control signal is an amplitude modulation signal, the level of each control signal demodulated on the booster 30a side also becomes smaller than expected, There is a possibility that the desired gain adjustment cannot be performed. However, when the frequency-modulated modulation control signal is transmitted to the booster 30a side, desired gain adjustment can be performed even if the level of the modulation control signal decreases.

In both of the above-mentioned embodiments, PIN diodes are used as the respective state changing means so that the attenuation amount can be continuously changed. For example, as shown in FIG. 8, one electronic switch or relay 220 is used. It is also possible to use state changing means for changing the amount of attenuation in two steps. Further, it is of course possible to further increase the number of electronic switches to change the attenuation amount in multiple stages. In this case, each frequency variable oscillation circuit 114, 116, 118 also
An electronic switch may be used to shift the frequency of each control signal stepwise. Or 2 as shown in FIG.
Two electronic switches or relays 222 and 224 may be used to switch between a state in which the band elimination filter 226 is inserted between the amplification stages and a state in which the band elimination filter 226 is not inserted to eliminate the interference wave. Further, in the above embodiment, the variable attenuator is used as the state changing means, but it is also possible to use the variable gain amplifier. Further, in the above embodiment, the attenuation amounts of the three state changing means are changed, but the attenuation amounts of a larger number of state changing means can be changed by increasing the number of control signals. Further, in the above embodiment, each state changing means is provided in each different amplifier, but the attenuation amount of a plurality of state changing means provided in one amplifier may be adjusted, or the attenuation of the state changing means may be adjusted. In addition to adjusting the amount, the interference wave may be removed by switching between insertion and non-insertion of a band elimination filter provided as a state changing means separately from these state changing means. Further, in the above-mentioned embodiment, the modulation control signal is superimposed on the DC voltage for operating the amplifier, but the modulation control signal may be superimposed on the AC voltage for operating the amplifier.
It

[0021]

As described above, in the remote control amplifier according to the present invention, the operating power supply output and the output signal of the amplifying means have different fundamental frequencies, respectively, and have different non-overlapping ranges.
Multiple control signals that are frequency-shifted individually by
A carrier wave with a frequency different from the output and output signals of the amplification means
The modulated modulation control signal is demodulated into a control signal and demodulated
Since the control signal is demultiplexed and converted to obtain the state adjustment signal of the level according to the frequency deviation, the output signal of the amplification means and the
In the case of having a plurality of state changing means, particularly three or more state changing means without affecting the operating power supply output , each of these state changing means can be finely adjusted individually. Further, in the control device according to the present invention, the modulation control signal obtained by modulating the signals of the respective different fundamental frequencies with the control signal obtained by individually frequency-shifting is superimposed on the power supply output. It is not necessary to limit the power output of the AC power supply to an AC power supply, and it is possible to change the state of any number of remote control amplifiers that operate with either AC power supply or DC power supply.
These can be controlled even if a means is provided .
Moreover, since this modulation control signal can be superimposed on the power supply output by mutual inductive coupling, when the modulation control signal is extracted from the superimposed signal of the power supply output and the modulation control signal on the remote control amplifier side, the DC There is no need to use a high-frequency choke with a large resistance, and no voltage drop occurs at the power supply output. Further, since an unbalanced attenuator having an asymmetric constant selected is provided between the mutual induction circuit and the modulation control signal generating means to perform impedance control, leakage of harmonics of the modulation control signal does not occur. Also, modulation control
Frequency modulation circuit can be used for the signal generation means
Thus, even if the modulation control signal is attenuated on the transmission line, the state changing means can be controlled well.

[Brief description of drawings]

FIG. 1 is a block diagram of a first embodiment of a remote control amplifier and its control device according to the present invention.

FIG. 2 is a circuit diagram showing an example of a state changing means used in the first embodiment.

FIG. 3 is a detailed block diagram of a control unit and a modulation unit used in the first embodiment.

FIG. 4 is a diagram showing frequencies and levels of modulation control signals used in the first embodiment.

FIG. 5 is a detailed block diagram of a demodulation unit and a demultiplexing conversion unit used in the first embodiment.

FIG. 6 is a frequency characteristic diagram of the band amplification circuit used in the first embodiment.

FIG. 7 is a block diagram of the second embodiment.

FIG. 8 is a circuit diagram showing another example of the state changing means used in the both embodiments.

FIG. 9 is a circuit diagram showing still another example of the state changing means used in the both embodiments.

FIG. 10 is a circuit diagram of a conventional remote control amplifier and its control device.

[Explanation of symbols]

 30 30a Booster 32 32a Power supply and control device 42 50 62 State changing means 74 Output terminal 88 Demultiplexing converter 92 Superimposing circuit 112 Controller 150 Modulator

Claims (7)

(57) [Claims] 1. A signal condition according to the level of a status adjustment signal.
It has a plurality of state changing means whose states can be changed.
Means for outputting the signal to the transmission line, and the operation power supply output and the modulation control signal for the amplifying means.
The above modulation control signal is extracted from the superimposed superimposed signal and
The modulation control signal is the same number of control signals as the state changing means.
Depending on the composite signal of
Modulated carrier wave of different frequency from the output signal of the stage
Where the control signal is the operating power supply output and the modulation control signal.
Have fundamental frequencies with different frequencies and
Individual frequency deviations from the fundamental frequency within non-overlapping ranges of each other
And a demodulation means for demodulating the extracted modulated control signal into the combined signal, and the demodulated combined signal is demultiplexed into each of the control signals, and then according to the frequency deviation. And a demultiplexing conversion means for converting the signal into a state adjustment signal of a different level and supplying it to the corresponding state changing means. 2. A signal condition according to the level of a status adjustment signal.
It has a plurality of status change means that can change the status
A remote controller that outputs the output signal of the above-mentioned state changing means via a line.
To the remote control amplifier via the transmission line
The operating power source output generating means for generating the operating power source output, the output signal of the amplifying means and the operating power source output are
Separate oscillation signals of different fundamental frequencies within the non-overlapping range
Frequency-shifted to the same number of control signals as the above state changing means.
Output signal of the amplifying means, which is a composite signal of the control signal generating means for generating
And a carrier wave of a frequency different from that of the above operating power supply output
A remote control amplifier comprising: a modulation control signal generation unit that modulates or frequency modulates to generate a modulation control signal; and a superposition unit that superimposes the modulation control signal on the operating power supply output so as to be transmitted to the remote control amplifier. Control device. 3. The control device for a remote control amplifier according to claim 2, wherein the superimposing means performs the modulation control signal on the output of the operating power supply by mutual inductive coupling. 4. The remote control amplifier control device according to claim 3, wherein an unbalanced attenuator is provided between the superimposing means and the modulation control signal generating means. Amplifier controller. 5. A signal condition according to the level of a status adjustment signal.
An amplifying means having a plurality of state changing means for changing the state; a transmission line through which the output of the amplifying means is transmitted; and a transmission line provided on the opposite side of the transmission line from the amplifying means and supplied to the transmission line. An operating power supply output generating means for generating an operating power supply output to the amplifying means, and an amplifying means of the amplifying means provided on the operating power supply output generating means side .
Output signal and fundamental frequency different from the above operating power supply output
Control signal generating means for generating control signals by individually frequency-shifting a number of oscillation signals within a non-overlapping range, and a composite signal of the control signals, and an output signal of the amplifying means.
And modulates a carrier wave with a frequency different from the above operating power output.
Transmission means for generating a modulation control signal and superimposing it on the operating power supply output and transmitting it to the amplifying means side by the transmission line, and the operating power supply output provided on the amplifying means side and transmitted through the transmission line. And demodulation means for extracting the modulation control signal from the superposition signal of the modulation control signal and demodulating the modulation control signal into the composite signal, and demultiplexing the demodulated composite signal into the control signals. A remote control amplifier and its control device, comprising: demultiplexing conversion means for converting into a status adjustment signal having a level corresponding to the frequency deviation and supplying the status adjustment means to the corresponding status changing means. 6. The remote control amplifier and its control device according to claim 5, wherein said transmission means has amplitude modulation means .
Remote control amplifier and a control system, characterized in that that. 7. The remote control amplifier and the control device therefor according to claim 5, wherein said transmission means has frequency modulation means .
A remote control amplifier and its control device.