JP2002034058A - Method and equipment for measuring receiving level of cs broadcast dual antenna - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an equipment for measuring the receiving level of a CS broadcast dual antenna in which the maximum value of a meter can be set at one position at the time of adjusting the direction of a dual antenna and the direction can be adjusted surely and easily while reducing the cost. SOLUTION: A signal from a dual antenna 10 comprising first and second converters 12, 13 corresponding to two satellites is inputted to a tuner 21. A channel set signal set by a channel set circuit 24 is inputted to the tuner 21 while being switched by a channel select switch 25. The channel set circuit 24 outputs a channel set signal corresponding to the broadcast channel of a frequency used by only one of two satellites. A signal being transmitted from the dual antenna 10 to the tuner 21 is received according to the channel set signal, and an AGC signal outputted from the tuner 21 is amplified by a current amplifier 34 and used for driving a meter 35.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for measuring a reception level of a CS broadcasting dual antenna.

[0002]

2. Description of the Related Art In recent years, the number of satellite broadcasts such as BS broadcasts and CS broadcasts has been increasing. In CS broadcasting (CS digital broadcasting), JC-SAT3 and JC-S are arranged on the same orbit at very narrow intervals, for example, at an angle of 4 °.
AT4 satellite has been launched. The above JC-SA
CS transmitted from T3 and JC-SAT4 satellites
Broadcasts can be received by dedicated parabolic antennas, but recently, two C
A CS broadcast dual antenna capable of receiving S broadcast has been put to practical use. This CS broadcast dual antenna has two parabolic reflectors and two converters, ie, a JC-SAT3 broadcast receiving converter and JC-SAT3.
-A SAT4 broadcast receiving converter is provided.

[0003]

The CS broadcast dual antenna is very convenient because one antenna can receive two CS broadcasts. However, when a CS broadcasting dual antenna is installed, its position must be adjusted so as to correspond to two satellites, and the adjustment is very troublesome. In general, the direction of the antenna is adjusted while checking the television reception image. However, since the television receiver is installed at a place away from the antenna, it is difficult to adjust the direction of the antenna by one person. For this reason, a level meter that can check the level of the received signal of the antenna at the place where the antenna is installed or near the antenna has been put to practical use.

[0004] The conventional level meter described above broadcasts JC-SAT3 and JC-SAT output from two converters.
SAT No. 4 broadcast is received, and the level of the received signal is displayed on a meter. At the time of adjustment, if the direction of the antenna is roughly adjusted to the direction of the satellite and then the antenna is moved to the left and right, the deflection of the meter increases when the direction of the antenna matches the direction of the satellite. However, since broadcast radio waves are output from two satellites, a part conforming to JC-SAT3 and a part conforming to JC-SAT4
The maximum value of the meter appears at two places where the number matches the number, and it is not possible to confirm where the optimum place is. In addition, both radio wave of each other to effect deflection of the meter by receiving broadcast waves from two satellites changes complicated, it is difficult to any point for this is to check whether the optimum direction.

Further, the conventional level meter is configured to take out an intermediate frequency signal output from an internal tuner and measure the signal level. Therefore, the frequency of the signal to be handled is high and the level of the measuring circuit is increased. However, there is a problem that the cost becomes high and the cost becomes high.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. When adjusting the direction of the antenna, the maximum value of the meter can be set to one position, and the direction can be adjusted reliably and easily. It is an object of the present invention to provide a method and apparatus for measuring the reception level of a CS broadcasting dual antenna which can reduce the cost.

[0007]

According to a first aspect of the present invention, a tuner receives an output signal of a CS broadcasting dual antenna provided with two converters corresponding to two satellites, and uses the AGC signal output from the tuner to output the antenna. In the method for measuring the reception level of a CS broadcast dual antenna, the reception channel of the tuner is set to a broadcast channel of a frequency used by only one of the two satellites, and the level of the reception radio wave is set. It is characterized by measuring.

A receiving level measuring apparatus for a CS broadcasting dual antenna according to a second aspect of the present invention includes a tuner for receiving an output signal of a CS broadcasting dual antenna provided with two converters corresponding to two satellites, and an output from the tuner. A
A current amplifier for amplifying a GC signal; a meter driven by an output signal of the current amplifier; and channel setting means for setting a reception channel of the tuner, wherein the channel setting means sets a reception channel of the tuner. A broadcast channel of a frequency used by only one of the two satellites is set.

A receiving level measuring apparatus for a CS broadcasting dual antenna according to a third aspect of the present invention includes a tuner for receiving an output signal of a CS broadcasting dual antenna having two converters corresponding to two satellites, and an output from the tuner. A
A current amplifier for amplifying the GC signal; a meter driven by an output signal of the current amplifier; channel setting means for outputting a plurality of channel setting signals for the tuner; and a channel setting signal output from the channel setting means. A tuning switch for selecting and inputting to the tuner, wherein the channel setting means outputs a plurality of channel setting signals corresponding to a broadcast channel of a frequency used by only one of the two satellites. It is characterized by the following.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a circuit configuration diagram of a CS broadcast dual antenna reception level measuring apparatus according to an embodiment of the present invention. In the figure, reference numeral 10 denotes a CS broadcast dual antenna, and a JC
-First converter 1 for SAT3 broadcast (PerfecTV)
2 and a second converter 13 for JC-SAT4 broadcast (JSkyB). The output signals of the first converter 12 and the second converter 13 are mixed by a mixer 14 and output from a coaxial connector 15 provided in the mixer 14. CS broadcasting dual antenna 1
As 0, those having a local oscillation frequency of "11.2 GHz" and those having a local oscillation frequency of "10.678 GHz" have conventionally been generally used.

When receiving a CS broadcast by a television receiver, a connection is made from a coaxial connector 15 of the mixer 14 to a CS tuner (not shown) via a coaxial cable. When measuring the level, the coaxial connector 15
6 and connected to a receiving level measuring device (level meter) 20 of a CS broadcasting dual antenna. In addition, the above CS
The broadcast dual antenna 10 is connected to the C of the television receiver.
It operates with an S tuner or a DC power supply supplied from the reception level measuring device 20.

The reception level measuring device 20 includes a tuner 21 for receiving a CS broadcast. Tuner 21 above
Has an antenna input terminal 22 and a tuner output terminal 23
The antenna input terminal 22 is connected to the coaxial connector 15 of the mixer 14 via a coaxial cable 16.
Connected to. The tuner 21 has an antenna input terminal 22
The received signal input to the tuner output terminal 23
Output to A CS tuner of a television receiver is connected to the tuner output terminal 23 by a coaxial cable as needed.

In the tuner 21, a plurality of channel setting signals output from a channel setting circuit 24 are selected by a tuning switch 25 and input to a TUV terminal. The channel setting circuit 24 is a JC-SAT3
For example, JC-SAT4 can be used to receive a channel transmitted by only one of JC-SAT4 and JC-SAT4.
3 broadcast channel JD25 (transmission frequency 1
2.428 GHz). The tuning switch 25 is provided in accordance with the type of the CS broadcast dual antenna 10, that is, the CS broadcast dual antenna 10
Selects the channel setting signal of the channel setting circuit 24 corresponding to the local oscillation frequency used by the tuner 2.
1 to the TUV terminal. In this case, tuning switch 2
5 is a dual antenna having a local oscillation frequency of “11.2 GHz”, and the selected channel # 2 is a dual channel having a local oscillation frequency of “10.678 GHz”.
z "dual antenna.

In FIG. 1, the channel setting circuit 24
In addition to the channels # 1 and # 2, channels # 3 to # 6 can be further selected by the channel selection switch 25. This is a dedicated channel for receiving radio waves of other CS satellites and BS satellites. When an antenna is installed, the reception level of the corresponding satellite radio wave can be measured.

The LNB terminal of the tuner 21 is supplied with an operating voltage of, for example, 12 V from a DC power supply 26 via a power switch 27a, a protection circuit 28, which will be described in detail later, and a power line 29. As the DC power supply 26, for example, eight 1.5V batteries are used to obtain a total voltage of 12V.

The tuner 21 has a tuner output terminal 2
3 is connected to a CS tuner of a television receiver, for example, 12 V supplied from the CS tuner.
Is output to the antenna input terminal 22 and the LNB terminal. In this case, the DC voltage output from the LNB terminal to the power supply line 29 is not affected by the DC power supply 26 by the protection circuit 28. An LED 31 is connected between the power supply line 29 and the ground line GND via a resistor 32.

Further, 1 supplied to the power supply line 29
The voltage of 2V is supplied to the channel setting circuit 24, and is also converted to a voltage of, for example, 5V by the voltage conversion circuit 33 and supplied to the tuner 21 as an operating voltage.

The AGC signal output from the tuner 21 is amplified by a current amplifier 34 and
Drive. The details of the current amplifier 34 will be described later. The meter 35 is, for example, 200 μA,
One end is connected to the power supply line 29, and the other end is connected to the output terminal of the current amplifier 34 via the power switch 27b. The current amplifier 34 is provided with a sensitivity adjustment volume 36 for adjusting the state of movement of the hand of the meter 35.

The power switches 27a and 27b operate in conjunction with each other and have three terminals a, b and c switched by a movable contact d. The terminal a of the power switch 27a is power OFF, the terminal b is power ON, the terminal c is a terminal for power check (CHECK), the terminal a is open, the terminals b and c are connected to + terminals of the DC power supply 26,
The common contact d is connected to the protection circuit 28. The terminals a and b of the power switch 27b are connected to the output terminals of the current amplifier 34, the terminal c is connected to the ground line GND via the variable resistors 37 and 38, and the movable contact d is connected to the meter 35.
Connected to.

FIG. 2 shows a circuit configuration of the protection circuit 28. The input terminal T1 of the protection circuit 28 is connected to the emitter of, for example, a PNP transistor 41 via a resistor 40, and the collector is connected to the output terminal T2 via a diode 42 in the forward direction. A resistor 43 and a large-capacity capacitor 44 are connected in parallel to the resistor 40. Further, a resistor 45 is connected between the emitter and the base of the transistor 41, and a collector-base resistor 46 is connected. Further, the input terminal T1 is connected to the emitter of a PNP transistor 47, for example.
Its base is connected to the base of the transistor 41. The collector of the transistor 47 is connected to the base of the transistor 41 and to the ground line GND via the resistor 48. The protection circuit 28 includes:
As shown in FIG. 1, the DC power supply 26 is connected to the power switch 27a.
, And the output terminal T2 is connected to the power supply line 29.

The protection circuit 28 includes a power switch 27
a and 27b are turned on, the DC power supply 26
1 to turn on the transistor 41. Therefore, the DC power supply 26 supplied to the input terminal T1 is
Is output to the power supply line 29 via the diode 42 and the output terminal T2.

In the above state, when a large current larger than a predetermined value flows through the load circuit of the protection circuit 28, the voltage drop due to the resistors 40 and 43 increases, the base voltage of the transistor 47 decreases, and the transistor 47 is turned on.
Then, a reverse bias voltage is applied to the base of the transistor 41. Therefore, the transistor 41 is turned off to protect the load circuit. The above state is maintained by the charging voltage of the large-capacity capacitor 44.

When the load circuit is cut off by the protection circuit 28 as described above, the power switches 27a and 27b are turned off.
After the FF is performed and the load circuit returns to normal, the power switches 27a and 27b are turned on again. Power switch 27
Once a and 27b are turned off, the electric charge charged in the capacitor 44 is discharged through the resistors 40 and 43 and returns to the initial state. When the power switches 27a and 27b are turned on again, the transistor 41 is turned on and the power supply line is turned off. 29 is supplied with a DC power supply 26. Further, the diode 42 has a voltage supplied from a CS tuner of the television receiver,
It has the function of shutting off the DC power supply 26.

FIG. 3 shows a circuit configuration of the current amplifier 34. A diode 52 and a semi-fixed resistor 53 are provided in series between the AGC signal input terminal 51 and the ground line GND, and a capacitor 54 is provided in parallel with the semi-fixed resistor 53. The sliding terminal of the semi-fixed resistor 53 is connected to, for example, the base of an NPN transistor 57 via a resistor 55 and to the emitter via a resistor 56. This emitter and ground line GV
D, the sensitivity adjustment volume 36 is provided. The collector of the transistor 57 is connected to the meter 35 via the power switch 27b.

In the above configuration, the signal level of the AGC signal input from the tuner 21 to the current amplifier 34 is adjusted by the semi-fixed resistor 53 so that the transistor 57
Is input to The transistor 57 receives the input AGC
The signal is current amplified and the meter 35 is driven. in this case,
The deflection of the needle in the meter 35 is adjusted by the sensitivity adjustment volume 36.

FIG. 4 shows that in the current amplifier 34, the value of the semi-fixed resistor 53 is [100 KΩ], the value of the resistor 55 is [160 KΩ], the value of the resistor 56 is [33 KΩ], and the value of the sensitivity adjustment volume 36 is To [0Ω], [1.2K
Ω], [2.5 KΩ], and [5 KΩ] are shown to show the relationship between the input current and the output current.

FIG. 5 shows an external configuration of the reception level measuring device (level meter) 20. Case 6
An antenna input terminal 22 and a tuner output terminal 23 are provided above 0. A meter 35 is provided on the upper side of the front surface of the case 60, and an LED is provided near the meter 35.
31 are arranged. Further, on the front surface of the case 60, a local oscillation frequency as the channel selection information below the meter 35 is, for example, [1. Sky Perfec 11.2 GHz], [2. Sky Perf
ec 10.678 GHz], and a power switch 27 (27a, 27b) is provided. In the vicinity of the power switch 27, "OFF", "ON", "CHECK"
Is printed. On the right side of the case 60, a sensitivity adjustment volume 36 and a tuning switch 25 are provided.

Next, an operation procedure for adjusting the direction using the reception level measuring device 20 when the dual antenna 10 for CS broadcasting is installed will be described. First, the satellite is installed in accordance with the general direction of the CS satellite that receives the dual antenna 10, in this case, JC-SAT3 and JC-SAT4. Then, as shown in FIG. 1, the coaxial connector 15 of the dual antenna 10 and the antenna input terminal 22 of the reception level measuring device 20 are connected by the coaxial cable 16, and the tuning switch 25 is set to the type of the dual antenna 10, that is, , Set according to the local oscillation frequency. That is, the dual antenna 10 is set to “11.
2GHz "local oscillation frequency,
The channel # 1 is selected by the tuning switch 25, and when the dual antenna 10 uses the local oscillation frequency of “10.678 GHz”, the channel # 2 is selected by the tuning switch 25. When the converters 12 and 13 are operated by the power supply of the reception level measuring device 20, nothing is connected to the tuner output terminal 23.

Then, the sensitivity adjustment volume 36 is set to the middle state, and the power switch 27 is turned on. ON of the power switch 27 can be confirmed by lighting of the LED 31. When the power switch 27 is turned on,
DC power supply 26 is connected to L of tuner 21 via protection circuit 28.
The signal is input to the NB terminal, and the mixer 14 and the converters 12, 1,
3 is supplied. Thus, converters 12 and 13 start the receiving operation. In this case, the tuner 21 uses the JC-
In order to receive a channel transmitted by only one of SAT3 and JC-SAT4,
In this embodiment, a setting is made so that a broadcast channel JD25 (transmission frequency 12.428 GHz) in JC-SAT3 can be received.

The first converter 12 has a JC-SAT3
When a local oscillation frequency of "11.2 GHz" is received when receiving a signal of channel JD25 (vertically polarized wave) having a frequency of 12.428 GHz transmitted from the signal, the frequency is 1228 MHz.
And a local oscillation frequency of “10.678 GHz
In the case of "z", the signal is converted into a signal of 1750 MHz and output. On the other hand, JC-SAT4 is the broadcast channel J
Since the broadcast of the frequency corresponding to D25 is not performed,
The broadcast channel J is output from the second converter 13.
No signal of the frequency corresponding to D25 is output.

Accordingly, the tuner 21 receives the “1228 MHz” signal output from the first converter 12 when the channel # 1 is selected, and outputs the signal when the channel # 2 is selected. Is "1750MH
z ".

In the above state, when the elevation angle and the polarization angle of the installed dual antenna 10 are temporarily fixed and the antenna is moved left and right, for example, from the east side to the west side, the tuner 21 is output when the first converter 12 outputs a reception signal. Outputs an AGC signal, and the meter 35 fluctuates in accordance with the strength of the AGC signal. When the fluctuation of the meter 35 is extremely small or large, the sensitivity is adjusted by the sensitivity adjustment volume 36.

Next, the dual antenna 10 is moved up and down and stopped at the position where the pointer of the meter 35 is at the maximum. The elevation angle and the polarization angle of the dual antenna 10 are adjusted as described above, and the reception level is fixed at the maximum position.

When the direction of the dual antenna 10 is adjusted, the level of the received radio wave is measured by selecting the channel on which the radio wave is transmitted from only one satellite, that is, JC-SAT3. There is only one maximum swing point, and JC-SAT3 and JC-S
Since the radio wave of AT4 does not affect each other, the maximum point of the received radio wave can be confirmed reliably and easily.

When the direction to the first converter 12 for receiving the JC-SAT3 transmission radio wave is correctly adjusted, the direction to the second converter 13 for receiving the JC-SAT4 transmission radio wave is also correctly adjusted. Is done. Therefore, it is not necessary to adjust the direction of JC-SAT4 again.

Therefore, after the above adjustment operation is completed, the reception level measuring device 20 is detached from the dual antenna 10 and the CS tuner of the television receiver is connected, so that the television receiver can receive JC-SAT3 and JC-SAT.
-It is possible to receive CS broadcast radio waves transmitted from SAT4 in the best condition. In addition, dual antenna 1
When a power supply system abnormality occurs on the 0 side and an excessive current flows, the protection circuit 28 operates to cut off the power supply to the power supply line 29 to protect the circuit.

The case where the power of the reception level measuring device 20 is supplied to the dual antenna 10 to measure the level has been described above. However, the case where the power from the CS tuner of the television receiver is supplied to the dual antenna 10 is described. Sets the power switch 27 of the reception level measuring device 20 to O.
FF is performed, and a CS tuner of the television receiver is connected to the tuner output terminal 23 by a coaxial cable. When the CS tuner of the television receiver is connected to the tuner output terminal 23, the voltage supplied from the CS tuner is output to the converters 12 and 13 via the antenna input terminal 22 and the power supply line 2 is connected from the LNB terminal of the tuner 21.
9 is output. Therefore, even when the power switch 27 is turned off, the reception level measuring device 20 operates normally by the power from the CS tuner.

Therefore, the elevation angle and the polarization angle of the dual antenna 10 can be adjusted in the same manner as when the power supply of the reception level measuring device 20 is used as described above. Even if the power switch 27 is turned on while the CS tuner is connected to the tuner output terminal 23 of the tuner 21, the diode 42 of the protection circuit 28 cuts off the connection between the DC power supply 26 and the power from the CS tuner. So there is no particular problem.

To check the state of wear of the DC power supply 26, the power switch 27 is switched to the position of CHECK. At this time, the DC power supply 26 is supplied to the meter 35 via the variable resistor 37 and the resistor 38, and the needle of the meter 35 swings according to the consumption state of the DC power supply 26, so that the quality of the DC power supply 26 can be confirmed.

In the above embodiment, the case where the channel setting circuit 24 outputs a channel setting signal corresponding to one broadcast channel having a frequency used by only one of the two satellites has been described. In addition, a plurality of broadcast channels of a frequency used by only one satellite are set in the channel setting circuit 24, and for example, a JC-S
In addition to the broadcast channel JD25 (transmission frequency 12.428 GHz) in AT3, the same polarization system as JD25, in this case, vertically polarized JD21 (transmission frequency 1)
2.348 GHz), JD23 (transmission frequency 12.38)
8 GHz) or the like, and the channel setting signal is switched by the tuning switch 25 to set the tuner 21.
May be input.

With the above configuration, the broadcast channel of the frequency used by only one of the two satellites is set in advance even if the other satellite is used in the future. The direction adjustment of the dual antenna 10 can be surely and easily performed using the other broadcast channels set.

[0042]

As described above in detail, according to the present invention, C
When adjusting the direction of the S-broadcast dual antenna, the channel of the frequency used by only one satellite is selected and the level of the received radio wave is measured. Thus, the direction in which the reception level becomes maximum can be reliably and easily confirmed, and the direction of the dual antenna can be correctly adjusted.

In the present invention, the level of the received radio wave is measured using the AGC signal output from the tuner, so that the meter can be driven only by current-amplifying the AGC signal. Therefore, the circuit configuration can be simplified, and the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a circuit configuration diagram of a reception level measuring device for a CS broadcasting dual antenna according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a protection circuit in the embodiment.

FIG. 3 is a configuration diagram of a current amplifier in the embodiment.

FIG. 4 is a diagram showing a relationship between an input current and an output current of the current amplifier according to the embodiment.

FIG. 5 is an external configuration diagram of a reception level measuring device in the embodiment.

[Explanation of symbols]

 Reference Signs List 10 dual antenna 11 parabolic reflector 12 first converter 13 second converter 14 mixer 15 coaxial connector 16 coaxial cable 20 reception level measuring device (level meter) 21 tuner 22 antenna input terminal 23 tuner output terminal 24 channel setting circuit 25 Tuning switch 26 DC power supply 27 Power switch 28 Protection circuit 29 Power supply line 31 LED 33 Voltage conversion circuit 34 Current amplifier 35 Meter 36 Sensitivity adjustment volume

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5C061 BB03 CC05 5C064 DA08 5K042 AA05 CA17 CA23 DA19 FA01 HA02 JA01 NA04 5K062 AA09 AB12 AC01 AD01 AD09 AF04 AG01 BA01 BB02 BD01 BE08

Claims (3)

[Claims] 1. A CS broadcasting dual antenna for receiving an output signal of a CS broadcasting dual antenna provided with two converters corresponding to two satellites by a tuner and measuring a reception level of the antenna based on an AGC signal output from the tuner. The receiving channel of the tuner is set to a broadcasting channel of a frequency used by only one of the two satellites, and the level of the received radio wave is measured. How to measure the reception level of the antenna. 2. A tuner for receiving an output signal of a CS broadcasting dual antenna including two converters corresponding to two satellites, a current amplifier for amplifying an AGC signal output from the tuner, and an output signal of the current amplifier. And a channel setting means for setting a reception channel of the tuner, wherein the channel setting means sets the reception channel of the tuner to a frequency used by only one of the two satellites. C which is set to the broadcast channel of
S broadcast dual antenna reception level measurement device. 3. A tuner for receiving an output signal of a CS broadcasting dual antenna including two converters corresponding to two satellites, a current amplifier for amplifying an AGC signal output from the tuner, and an output signal of the current amplifier. , A channel setting means for outputting a plurality of channel setting signals for the tuner, and a tuning switch for selecting a channel setting signal output from the channel setting means and inputting the signal to the tuner. A receiving level measuring device for a CS broadcasting dual antenna, wherein the channel setting means outputs a plurality of channel setting signals corresponding to a broadcasting channel of a frequency used by only one of the two satellites.