JPS6214962B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a television signal amplifier used to amplify the television signal received by an antenna and transmitted to the television receiver via the feed line. It consists of an amplification section connected to the antenna side end and a control section connected to the indoor end, and the TV signal is drawn in from the amplification section and from the control section via the above-mentioned feed line. This relates to a television signal amplifier that supplies power to the amplifier section, and remotely controls the gain adjustment of the amplifier section by sending an adjustment signal from the control section to the amplifier section via the above-mentioned power supply line. It is also an object of the present invention to provide a television signal amplifier that is capable of extremely accurate adjustment even when such an adjustment signal is superimposed on the television signal or power source power.

It has been known to provide an attenuation circuit near an antenna located at a high place, and to control this using a half-wave of AC power transmitted from the ground. but,
If half-wave control signals from the ground were sent using TV signal feed lines, for example, if there are two antennas, or if there are three or more antennas, each signal circuit must be connected individually. There are drawbacks that cannot be controlled. Therefore, it becomes necessary to install a large number of power supply lines.

Therefore, the present invention connects a plurality of antennas to the antenna side end of the television signal lead-in feeder line, and connects an amplifier circuit between each of the antennas and the antenna side end. ,
On the other hand, a control unit is connected to the indoor end of the power supply line, and the control unit supplies power for the power supply to the amplifier circuit via the power supply line, while the output signal from the amplifier circuit is In the television signal receiving device that is connected via the power supply line, the control section includes a plurality of oscillators each having a different oscillation frequency and each oscillating a voltage signal for gain adjustment, each of the oscillators and the above. and a plurality of voltage level adjusting elements respectively connected to the indoor end and each adjusting the voltage level of the voltage signal emitted from the oscillator and sending it to the power supply line. Further, a plurality of attenuation circuits for adjusting the gain of the television signal according to the voltage level of the voltage signal for gain adjustment are connected between each of the antennas and the antenna side end, respectively, and each of the attenuation circuits is connected to each of the antennas. Between the input end of the voltage signal for gain adjustment in the attenuation circuit and the antenna side end, voltage signals of frequencies corresponding to the oscillation frequencies of the plurality of oscillators and different from each other are attenuated, respectively. By connecting multiple signal extraction circuits that pass toward the input end of the circuit, even if there are many signal circuits for the antenna, each can be controlled individually using one TV signal feed line. It is something that makes it possible.

Prior to describing FIGS. 4 and 5, which show embodiments of the present application, FIGS. 1 to 3, which show techniques necessary for explaining the embodiments of the present application, will be described below. In FIG. 1, 1 is an antenna, 2 is an amplification section connected to the antenna, and is provided with an attenuation circuit 3, a signal extraction circuit 4, and the like. Reference numeral 5 denotes a feeder line for bringing in television signals, for example, a coaxial cable is used, and its antenna side end 5a is connected to the amplifying section 2. A control section 6 is connected to the signal lead-in end 5b of the power supply line 5. The control unit 6 also includes a power supply mechanism 7, an oscillator 8 that oscillates a voltage signal for gain adjustment, and a voltage signal level adjustment element 9 that can adjust the level of the voltage signal.
etc. are provided. 10 indicates a well-known television receiver.

Next, in FIG. 2 showing the amplification section 2 in detail, 11 is an input terminal, 12 and 13 are respective amplifier circuits, and 14 is an output terminal. The attenuation circuit 3 is
As shown in the figure, it is composed of a PIN diode _D1 , a DC blocking capacitor, a high frequency blocking coil, and the like. The signal extraction circuit 4 is configured to extract only the voltage signal for gain adjustment sent from the control unit 6.
5 is used. Note that this may be configured using a bandpass filter. Reference numeral 16 denotes a signal step-up transformer that is used as necessary, and for example, a transformer with a turns ratio n ₁ :n ₂ of 1:5 is used.
Reference numeral 17 denotes a control circuit, which adjusts the bias current of the PIN diode _D1 to control its high frequency resistance; for example, an operational amplifier 18
It is constructed using various resistors, capacitors, etc.

Next, in FIG. 3 showing an example of a circuit of the control unit 6, 21 is a power switch, 22 is an AC outlet, and 23 is a power transformer, which converts 100V AC to 20 to 30V.
A device that lowers blood pressure is used. 24 is a rectifier, 2
5 indicates a smoothing circuit. 26 is an input terminal, 27 is an output terminal, _C2 is a capacitor that passes only high frequency signals, and _L2 is a high frequency blocking coil. The oscillator 8 is configured using, for example, a tuning fork resonator 28 and an operational amplifier 29. Further, this oscillator 8 is configured to oscillate a gain adjustment signal having a frequency that matches the frequency of the signal extracted by the signal extraction circuit. Further, the voltage level adjustment element 9 is configured with a variable resistor VR ₁ as shown. A transformer 30 is used to efficiently send the oscillation output from the terminal 26 to the power supply line 5. Further, the turns ratio n ₁ :n ₂ of this transformer is such that n ₁ and n ₂ are the same, or n ₂ is made larger. Further, this transformer 30 is designed to operate as a chiyoke coil for smoothing the power supply. The frequency of the voltage signal for gain adjustment is set to a frequency that does not cause mutual interference with the high frequency signal received by the antenna 1 and sent to the television receiver 10 via the amplification section 2, feeder line 5, etc. It is something that can be done.

In the case of the above configuration, as is well known, from the power supply circuit 7 to the primary winding n ₁ of the transformer 30, the coil L ₂ ,
Power source power is sent to the power supply line 5 via the terminal 26 . This power is received from the terminal 14 in the amplifier section 2 and sent to the amplifier circuits 12, 13, the control circuit 17, etc. via the coil L ₁ and the primary winding n ₁ of the transformer 16.

Then, the signal received by the antenna 1 and input to the amplifying section 2 is amplified by the amplifying circuits 12, 13, etc., and is output from the output terminal 14 to the feed line 5.

This signal is transmitted to the television receiver 10 via the input terminal 26 and output terminal 27 of the control section 6.

In such a state, the voltage signal for gain adjustment generated by the oscillator 8 has its voltage level adjusted by the adjustment element 9, and is further transmitted to the transformer 30,
It is sent out from the terminal 26 to the power supply line 5 via the coil _L2 .

This signal amplifying section 2 is connected to a terminal 14 and a coil.
The signal is sent to the signal extraction circuit 4 via the _L1 transformer 16. The signal then passes through this signal extraction circuit 4 and is input to the control circuit 17. Then, this control circuit 17 controls the bias current of the PIN diode _D1 in the attenuation circuit 3 according to the voltage level of the voltage signal,
A high frequency resistance is generated in the PIN diode _D1 . Therefore, the high frequency signal (TV signal) received by the antenna and passed through the amplification section 2 is transmitted through the attenuation circuit 3.
is attenuated by

Therefore, the level of the signal received by the antenna and input to the television receiver 10 via the amplification section 2, feed line 5, and control section 6 is determined by the adjustment element 9 in the control section 6.
A desired value can be obtained by appropriately adjusting . In the case of this adjustment, since the gain adjustment signal sent from the control section 6 to the amplification section 2 via the feed line 5 is a voltage signal as described above, this signal is The power range is transmitted to the control circuit 17 in the amplifier section 2 almost unaffected by changes in the temperature of the power supply line 5, and accurate control can be performed.

In this example, a case is shown in which a television signal is received by the antenna 1 and transmitted to the television receiver 10 via the amplifying section 2 and the feed line 5, but the above signal is not limited to the television signal, but can also be AM or FM. The broadcast signal may be transmitted from the antenna to the receiver as described above.

Next, FIGS. 4 and 5 show embodiments of the amplification section and the control section, respectively, and include a plurality of antennas 1 ₁ , 1
This shows an example in which the signals received at nodes ₂ , 1, _{and 3} can be individually controlled.

Therefore, in this example, as is clear from FIG.
Multiple sets of 7e are also used.

Further, the signal extraction circuits 4 ₁ , 4 ₂ , 4 _{3 ,} etc. are configured to be able to select and pass only signals of different frequencies f ₁ , f ₂ , f _{3 ,} respectively. Note that 31 represents a mixer that mixes the signals inputted and amplified from the antennas 1 ₁ , 1 ₂ , and 1 ₃ into one.
Next, in the control section 6e shown in FIG. 5, a plurality of oscillators 8 ₁ , 8 ₂ , 8
₃ are used, and the frequencies f ₁ , f ₂ , f ₃ are respectively the same as the frequencies of the signals selected by the signal extraction circuit.
It is configured to oscillate a signal.

It should be noted that the same reference numerals as those in the previous figure are appended with an alphanumeric letter "e" for parts that are functionally the same or equivalent to those in the previous figure, and redundant explanations are omitted.

As described above, in the present invention, between the amplifier circuit 12 and the control unit 6 which are separated from each other, not only the television signal is drawn in and the power for the power source is supplied.
Even if remote control of gain adjustment is also performed, power for the power source is supplied via the feeder line 5 that draws in the output signal from the amplifier circuit 12, and the gain adjustment is also performed via the feeder line 5. Since the control unit 6 is designed to send a signal for
It has the advantage that only one power supply line 5 is required to connect the amplifier circuit 12 and the amplifier circuit 12. This has the effect of simplifying the installation work.

Furthermore, in the present invention, since an attenuation circuit is provided for each of the plurality of antennas, each antenna signal can be adjusted individually.
Moreover, as described above, these adjustments are made using a plurality of oscillators that have mutually different oscillation frequencies and that each oscillates a voltage signal for gain adjustment, and between each of the oscillators and the indoor end. a plurality of voltage level adjustment elements connected to each other, each of which adjusts the voltage level of the voltage signal emitted from the oscillator and sends it to the feed line; A plurality of attenuation circuits that adjust the gain of the television signal according to the voltage level of the voltage signal for gain adjustment are connected between each end of the antenna side, and a voltage for gain adjustment in each of the attenuation circuits is connected. Between each of the signal input end and the antenna side end, voltage signals of different frequencies corresponding to the respective oscillation frequencies of the plurality of oscillators are passed toward the input end of the attenuation circuit. Since multiple signal extraction circuits are connected to each other, it is possible to individually adjust a large number of antennas using the single feeder line, regardless of the number of antennas. It has its features.

Moreover, even if the present invention further superimposes a gain adjustment signal on the feeder line 5 through which television signals and power supply power are already flowing as described above,
Since a voltage signal is used as the signal, in other words, almost no current is involved.
When adjusting the gain, the signal is sent out from the control unit 6 as it is without being affected by the presence of the television signal or power source, or by temperature changes in the power supply line 5 along the way. The signal can be transmitted to the amplifier circuit 12, which has the effect of making extremely accurate and stable adjustment possible.

[Brief explanation of the drawing]

FIG. 1 is a block circuit diagram, FIG. 2 is a diagram showing an example of the circuit of the amplifier section, FIG. 3 is a diagram showing an example of the circuit of the control section, and FIGS. 4 and 5 are diagrams showing the embodiment of the present invention. Figure 4 is a block circuit diagram of the amplifier section, Figure 5 is a block circuit diagram of the amplifier section, and Figure 5 is a block circuit diagram of the amplifier section.
The figure is a block circuit diagram of the control section. 2... Amplification section, 5... Power supply line, 6... Control section,
3... Attenuation circuit, 4... Signal extraction circuit, 8... Oscillator, 9... Adjustment element.

Claims (1)

[Claims] 1 A plurality of antennas are connected to the antenna side end of the television signal lead-in feeder line, and an amplifier circuit is connected between each of the above antennas and the antenna side end, while the above A control section is connected to the indoor end of the feed line, and the control section supplies power for the power supply to the amplifier circuit via the feed line, while the output signal from the amplifier circuit is connected to the feed line. In the television signal receiving device, the control unit includes a plurality of oscillators each having a different oscillation frequency and each oscillating a voltage signal for gain adjustment, and a plurality of oscillators that have mutually different oscillation frequencies and each oscillating a voltage signal for gain adjustment, and a plurality of oscillators that connect each of the oscillators and the indoor end. and a plurality of voltage level adjustment elements respectively connected between the oscillator and the oscillator, each of which adjusts the voltage level of the voltage signal emitted from the oscillator and sends it to the power supply line; A plurality of attenuation circuits for adjusting the gain of the television signal according to the voltage level of the voltage signal for gain adjustment are connected between each of the antennas and the antenna side end, and each of the attenuation circuits Between the input end of the gain adjustment voltage signal and the antenna side end, voltage signals of different frequencies corresponding to the oscillation frequencies of the plurality of oscillators are respectively input to the attenuation circuit. A television signal receiving device characterized in that a plurality of signal extraction circuits are connected to each other so that the signal is passed toward the end.