JPS6374237A - Signal amplifier for semi-duplex communication equipment - Google Patents

Abstract

PURPOSE:To prevent the occurrence of howling or self-hold by comparing a reference voltage and a signal generated in one transmission line and amplifying the signal to output it to other transmission line and inhibiting the amplification of the signal of the other transmission line. CONSTITUTION:When a central controller 1 generates a Hi output, the Hi signal is fed to an inverted input terminal 5a of a 1st operational amplifier 5 via one transmission line 3a and a Low signal is generated at an output terminal 5c. On the other hand, the Hi signal generated at the output terminal 5c of the 1st operational amplifier 5 is fed to an inverting input terminal 6 via a jumper 14 to inhibit the amplification of a 2nd operational amplifier 6. Thus, howling or self-hold by a signal amplifier 4 is not caused.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to a half-duplex communication device (half-duplex).
(7) It relates to a signal amplification device provided on a transmission path.

[Prior Art] When the distance of the transmission line of a half-duplex communication device is lengthened, when a signal transmitted from a transmitter/receiver on one side of the transmission line passes through the long transmission line, the voltage of the signal may drop or Alternatively, noise may be mixed in, making it difficult to read the signal with the transmitter/receiver on the other side of the transmission path.

Therefore, between the transmission lines, a first amplifier that amplifies the signal sent from one side of the transmission line and a second amplifier that amplifies the signal sent from the other side of the transmission line are provided. Installation of equipment was requested.

[Problems to be Solved by the Invention] However, in the transmission line of a half-duplex communication device, for example, a first amplifier amplifies a signal sent from one side of the transmission line and transmits it to the other side of the transmission line. Then, the second amplifier amplifies the signal amplified by the first amplifier and sends it again to the first transmission line, which is then amplified again by the first amplifier and this process is repeated, causing howling and self-holding. It had a problem that could occur.

The present invention has been made in view of the above circumstances, and its purpose is to amplify signals sent from both sides in a transmission path of a half-duplex communication device without causing howling or self-holding. The purpose is to provide a signal amplification device.

[Means for Solving the Problems] In order to achieve the above object, the present invention is provided in a transmission line of a half-duplex communication device, and a signal generated on one side of the transmission line is amplified to amplify the signal generated on one side of the transmission line. In a signal amplifying device for a half-duplex communication device that transmits signals to the other side of the transmission line and also amplifies the signal generated on the other side of the transmission line and transmits the signal to one side of the transmission line, a first amplifier that compares and amplifies a signal generated on the other side of the transmission line with a reference voltage; a second amplifier that compares and amplifies a signal generated on the other side of the transmission path with a reference voltage; a first amplification inhibiting means for applying the output of the amplifier to the inverting input terminal of the second operational amplifier and inhibiting amplification of the second operational amplifier; Apply to the inverting input terminal,
A technical means further includes a second amplification inhibiting means for inhibiting amplification of the first cylinder amplifier.

[Operation and Effects of the Invention] In the present invention having the above configuration, when a signal is generated on one transmission line, the first operational amplifier compares and amplifies the signal with a reference voltage line and transmits the signal to the other transmission line. Output. As a result, a signal generated on one transmission line is amplified and transmitted to the other transmission line.

At this time, the output generated by the first operational amplifier is applied to the inverting input terminal of the second operational amplifier via the first amplification inhibiting means. As a result, while the first operational amplifier is amplifying the signal, the second operational amplifier is prohibited from amplifying the signal on the other transmission line, so that the second operational amplifier outputs the signal from the output of the first operational amplifier to the transmission line being used. No amplification is performed even if this occurs.

In other words, a signal generated on one transmission path can be amplified and transmitted to the other transmission path without causing howling or self-holding as in the prior art.

Further, when a signal is generated on the other transmission line, the second operational amplifier compares and amplifies the signal with the base voltage and outputs the amplified signal to the one transmission line. As a result, No. 15 generated on the other transmission path is amplified and transmitted to one transmission path.

At this time, the output generated by the second performance amplifier is applied to the inverting input terminal of the first performance amplifier via the second amplification inhibiting means. As a result, the first operational amplifier is prohibited from amplifying the signal on one transmission line while the second operational amplifier is amplifying the signal, so the first operational amplifier uses the output of the second operational amplifier on the other transmission line. No amplification is performed even if a signal is generated.

In other words, unlike conventional methods, the signal generated on the other transmission path is amplified without causing howling or self-holding, and -
It can be transmitted to 10,000 transmission lines.

[Embodiment 1-1] Next, a signal amplifying device for a half-duplex communication device according to the present invention will be described based on an embodiment shown in the drawings.

FIG. 1 shows a signal amplification device for a half-duplex communication device applied to a gas central heating system.

The centralized control ti11 device controller 1 connects gas heating equipment (slave unit) 2 installed in each room of a company, home, school, etc. to a transmission line from one room of the company, home, school, etc. or from a management center. It is remotely controlled via 3.

Generated from the central control device 1 to the gas heating device 2 (examples of FI include start and stop signals for each gas heating device 1, temperature setting signal, J!l hanging setting signal, gas cutoff valve closing signal, etc.) In addition, examples of signals generated from the gas heating device 2 to the central control device 2?1 include a fire signal, a gas out signal, a gas leak signal, an oxygen deficiency detection signal, an automatic check signal, etc. Signals detected by various Zenri devices attached to the device 2 are generated.

These signals are converted into a format corresponding to each signal and sent to the central control device 1 or the gas heating device 2.
It is output from

The format 1- used in this embodiment is a digital signal, and the voltage applied to the transmission line 3 is, for example, 12
It is set by the length of Low, which is a drop from volts (hereinafter referred to as 11i) to, for example, 0.7 to 2 volts (hereinafter referred to as Low).

If the transmission line 3 between the central control tIl device 1 and the gas heating system fIi 2 is specially provided, the voltage of the signal may change or noise may occur when the Low signal passes through the long transmission line 3. The signal may become difficult to read due to contamination.

Therefore, in the transmission line 3 between the central control device 1 and the gas heating device 2, the Low signal generated on one transmission line 3a is restored to the initial signal and transmitted to the other transmission line 3b. First signal generated on the other transmission line 3b! A signal amplifier 4 is provided which restores the signal to a signal of 17] and transmits it to one transmission line 3a.

This signal amplifying device 4 includes a first shearing amplification device (a comparator in this embodiment) 5 that compares and amplifies the voltage of one transmission line 3a and a reference voltage (for example, 6 volts), and
A second operational amplifier (a comparator in this embodiment) 6 is provided to compare and amplify the voltage of b and the base t% lightning voltage.

The inverting input terminal 5a of the first operational amplifier 5 is connected to a coil 7 for high frequency cutting, and a diode 8 that blocks the flow of current from the inverting input terminal 5a side of the first operational amplifier 5 to the central control device 1 side. It is connected to the transmission line 3a on the - side via. The reference voltage applied to the non-inverting input terminal 5b of the first cylinder amplifier 5 is set by a constant voltage Zener diode 9.

In addition, the inverting input terminal 6a of the second operational amplifier 6 is connected via a coil 10 for high frequency cutting and a diode 11 that blocks the flow of current from the inverting input terminal 6a side of the second operational amplifier 6 to the gas heating device 2 side. and is connected to the other transmission line 3b. 31 inverting input terminal 6b of second performance amplifier 6
The reference voltage applied to the constant voltage Zener diode 1
2.

The output terminal 5c of the first distributive amplifier 5 is connected to the base of the transistor 13, which is the first switching element, and is also connected to the inverting input terminal 6a of the second operational amplifier 6 via the connection line 14. The connection side of the connection I214 to the inverting input terminal 6a is connected to the inverting input terminal 6a side of the diode 11. Further, this connection line 14 is provided with a diode 15 that prevents the current from the other transmission line 3b from being applied to the output terminal 5c of the first operational amplifier 5. This connection line 14 and diode 15 constitute a first amplification inhibiting means 16 of the present invention.

Further, the collector of the transistor 13 is connected to the other transmission line 3b on the gas heating device 2 side than the diode 11, and the emitter is grounded.

The output terminal 60 of the second amplifier 6 is connected to the base of the transistor 17, which is the second switching element f, and is also connected to the inverting input terminal 5a of the first operational amplifier 5 via the connection line 18. . The connection side of this connection line 18 to the inverting input terminal 5a is connected to the inverting input terminal b from the diode 8.
Connected to side a. Moreover, this connection line 18 has -
The current in the transmission line 3a is connected to the output terminal 6 of the second operational amplifier 6.
A diode 19 is provided to prevent the voltage from being applied to c. This connection line 18 and diode 19 constitute a second amplification inhibiting means 20 of the present invention.

The collector of the transistor 17 is connected to one transmission line 38 on the central control device 1 side via the diode 8, and the emitter is grounded.

Note that 21 is a constant voltage supply terminal that receives a constant voltage of, for example, 12 volts generated by a constant voltage (not shown) power source;
A constant voltage is supplied to each collector of the transistor 13.17 via each resistor, and a constant voltage is also supplied to various parts such as a constant voltage Zener diode 9.12.

Next, the operation of the above embodiment will be explained.

a) When the central control device 1 generates an output of tli.

When the centralized control til device 1 generates the old output, it is transmitted to the inverting input terminal 5a of the first operational amplifier 5 via one transmission line 3a.
The ljlli signal is applied. This inverting input terminal 5a
Since the signal of lli applied to is higher than the voltage applied to the non-inverting input terminal 5b, the first operational amplifier 5 generates a Low signal at the output terminal 5C. As a result, a LOW signal is applied to the base of the transistor 13, so
Transistor 13 is turned off.

When the transistor 13 is in the F state, the transistor 13
The 12 volt voltage applied to the collector side of the 12 volts via the constant voltage supply terminal 21 is not grounded.
Volt voltage is generated on the other transmission line 3bL.

As a result, even if the tli signal generated by the centralized control device 1 passes through one transmission line 3a (and arrives at the S9 amplification equipment 4, even if there is voltage fluctuation J3 and noise mixing) Since the old signal of 12 volts is restored again by the signal amplifying device 4 and transmitted to the other transmission line 3b, the gas heating device 2 can stably receive the lli signal.

b) When the central control device 1 generates a Low output.

When the central control device 1 generates an output of SI01#, the inverting input terminal 5 of the first operational amplifier 5 is output via one transmission line 3a.
A low signal is applied to a. This inverting input terminal 5a
Since the COW signal applied to the non-inverting input terminal 5b is lower than the voltage applied to the non-inverting input terminal 5b, the first operational sieve amplifier 5 generates a tli signal at the output terminal 5C. Since the signal 111 is applied, the transistor 13 enters the 014 state.

When the transistor 13 is in the ON state, the transistor 13
Since the 12 volt voltage applied to the collector side of the transmitter via the constant voltage supply terminal 21 is grounded, this ground voltage is generated on the other transmission line 3b.

On the other hand, the old signal generated by the output terminal 5C of the first operational amplifier 5 is applied to the inverting input terminal 6a of the second operational amplifier 6 via the tangent VC line 14. Since the signal of lli applied to the inverting input terminal 6a is higher than the reference voltage applied to the non-inverting input terminal 6b, the second Q amplifier 6 generates a signal of L-3 at the output terminal 6C.

That is, when the old signal is generated at the output terminal 5C of the first operational amplifier 5, the amplification of the second operational amplifier 6 is prohibited. Therefore, even if a tow signal 3 is generated in the other transmission line 3b due to the ON operation of the transistor 13, the transistor 17 is turned OFF, and the second operational amplifier 6
Also, since the influence of the transistor 17 is not exerted on the transmission line 3a of 7'J, howling and self-holding by the 8 amplifier device 4 do not occur.

As a result, the Low
When the signal passes through one transmission line 3a and reaches the signal amplifier 14, even if there is voltage fluctuation or noise, the signal is restored to a Low signal by the signal amplifier 4 and the signal is restored to the other signal. Since the signal is transmitted to the transmission line 3b of the fuel cell, the gas heating device 2 can stably receive the Low signal 3.

C) When the gas heating device 2 generates an output of lli.

When the gas heating device 2 generates an output of lli, the inverting input terminal 68 of the second operational amplifier 6 is transmitted via the other transmission line 3b.
An lli signal is applied to. Since the voltage 111 applied to the inverting input terminal 6a is higher than the voltage applied to the non-inverting input terminal 6b, the second operational amplifier 6 generates a Low signal at the output terminal 6C. As a result, LOW (AQ) is applied to the base of the transistor 17, so that the transistor 17 is turned off.

When transistor 17 is OFF, transistor 1
Since the 12 volt voltage applied to the collector side of 7 through the constant voltage supply terminal F21 is not grounded, this 1
A voltage of 2 volts is generated on one transmission line 3a.

As a result, when the lli signal generated by the gas heating device 2 passes through the other transmission line 3b and reaches the signal amplification device 4, the voltage is 9! ! ] and noise, the signal amplifier 4 restores it to a 12 volt tli signal and sends it to the -Buno transmission line 38, so the central control device 1 stably outputs the Ili signal. can be received.

d) When the gas heating device 2 generates a low output.

When the gas heating device 2 generates a Low output, the inverting input terminal 6 of the second f1 amplifier 6 is output via the other transmission line 3b.
A Low signal (ii) is applied to a. This Low signal applied to the inverting input terminal 6a is applied to the non-inverting input terminal 6b.
, the second operational amplifier 6 generates a signal of lli at the output terminal 6C.

As a result, the lli signal is applied to the base of the transistor 11, so that the transistor 17 is turned on.

When the transistor 17 is in the ON state, the transistor 17
Since the 12 volt voltage applied to the collector side of the transmitter via the constant voltage supply terminal 21 is grounded, this ground voltage is generated on one transmission line 3a.

On the other hand, the output terminal 6C of the second operational amplifier 6 generates tl
The signal i is applied to the inverting input terminal 5a of the first operational amplifier 5 via the connection line 18. Since the lli signal applied to the inverting input terminal 5a is higher than the reference voltage applied to the non-inverting input terminal 5b, the first amplifier 5 generates a tow signal at the output terminal 5C.

That is, when the lli signal is generated at the output terminal 6C of the second operational amplifier 6, the amplification of the first operational amplifier 5 is prohibited. Therefore, even if a Low signal is generated on one transmission path 3a due to the ON operation of the transistor 17, the transistor 13 is turned OFF, and the influence of the first amplifier 5 and the transistor 13 is transferred to the other transmission path. 3b, no howling or self-holding occurs in the signal amplifying device 4.

As a result, even if there are voltage fluctuations and noise mixed in when the Low signal generated by the gas heating device 2 passes through the other transmission line 3b and reaches the signal amplification device 4, the signal amplification device 4 Since the signal is restored to a Low signal and transmitted to one transmission path 38, the central control device 1 can stably receive the Low signal.

A second embodiment of the present invention will be explained in FIG.

In the above embodiment, the signal generated on the transmission line 3a of -1) is input to the inverting input terminal 5a of the first operational amplifier 5, and the signal generated on the other transmission line 3b is input to the inverting input terminal of the second operational amplifier 6. Although the signal input to the terminal 6a is shown, in this embodiment, the signal generated on one transmission line 3a is manually inputted to the non-inverting input terminal 5b of the first operational amplifier 5, and the signal generated on the other transmission line 3b is input. The signal is input manually to the No. 1 inverting input terminal 6b of the second operational amplifier 6.

According to this embodiment, when the signal 111 is generated on the transmission line 3a of -1, the first amplifier 5 generates the signal tli, turns on the transistor 13, and applies the voltage to the collector of the transistor 13. is generated on the other transmission line 3b. At this time, since the old signal of the first operational amplifier 5 is applied to the inverting input terminal 6a of the second operational amplifier 6, amplification of the second operational amplifier 6 is prohibited and the transistor 17 is turned off.
It is assumed to be in F state.

Furthermore, when the signal of the other transmission line 3bk:lli is generated, the second operational amplifiers 6 each generate the signal of Ili, and the voltage applied to the collector of the transistor 17 is transmitted to one side. 3a.

At this time, since the old signal is applied to the inverting input terminal 5a of the first operational amplifier 5, the second operational amplifier 6
Multiplier width unit 5 width is prohibited ~ transistor 13 is OFF
state.

A third embodiment of the present invention will be explained in FIG.

This embodiment uses the transistors 13 and 17 of the second embodiment described above.
has been abolished.

Note that the present invention is not limited to use in gas bundle heating systems, but can be used in communication equipment using all half-duplex communication devices, such as centralized control systems and mutual communication systems.

Further, in the above embodiment, an example was shown in which a comparator was used as an operational amplifier, but by using an operational amplifier, the present invention can be applied to a device that uses a frequency in a communication signal.

Furthermore, by adding a filter circuit, communication ability in areas with strong noise can be improved.

[Brief explanation of the drawing]

Fig. 1 is an electrical circuit diagram of a signal amplification device for a half-duplex communication device applied to a gas central heating system, Fig. 2 is an electrical circuit diagram adding a second embodiment of the signal amplification device, and Fig. 3 is It is an electrical 13 circuit diagram showing a third embodiment of the signal amplification device. In the figure: 1... Centralized side +1111 device 2... Gas heating device 3... Transmission line 3a... - Buch's transmission line 3
b...Other transmission line 4...Signal amplification device 5...
・1st output amplifier 6...2nd@9 amplifier 16...
・First amplification prohibition means 20...Second amplification prohibition means

Claims (1)

[Scope of Claims] 1) Provided on a transmission line of a half-duplex communication device, a signal generated on one side of the transmission line is amplified and transmitted to the other side of the transmission line, and a signal on the other side of the transmission line is amplified and transmitted to the other side of the transmission line. A signal amplifying device for a half-duplex communication device that amplifies a generated signal and transmits it to one side of the transmission line, comprising: a first operational amplifier that compares and amplifies the signal generated on one side of the transmission line and a reference voltage; , a second operational amplifier that compares and amplifies a signal generated on the other side of the transmission path with a reference voltage; and an output of the first operational amplifier is applied to an inverting input terminal of the second operational amplifier, a first amplification inhibiting means for inhibiting amplification of an operational amplifier; and a second amplification inhibiting means for applying an output of the second operational amplifier to an inverting input terminal of the first operational amplifier and inhibiting amplification of the first operational amplifier. A signal amplification device for a half-duplex communication device, characterized by comprising: 2) The signal amplification device for a half-duplex communication device according to claim 1, wherein the signal is a digital signal. 3) The half-duplex communication device according to claim 1 or 2, wherein the first operational amplifier includes a first switching element that amplifies the output of the first operational amplifier. Signal amplification device. 4) The half-duplex device according to any one of claims 1 to 3, wherein the second operational amplifier includes a second switching element that amplifies the output of the second operational amplifier. Signal amplification device for communication equipment.