JP3874625B2 - Time signal audio supply device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a time signal sound supply apparatus for providing a service for giving a time signal by voice through a telephone line in response to a user's request.
[0002]
[Prior art]
One of the services from the telephone office is a time signal voice supply service that announces a time signal in units of one second by voice. For this service, a time signal audio supply system is constructed on the telephone station side. As this hourly sound supply system, basically, there is a reference time device that generates accurate time data, and a voice synthesizing unit that generates a time signal sound from accurate time information from the reference time device. Good.
[0003]
However, the reference time device is very expensive, and it is not practical in terms of cost efficiency to provide this reference time device in every telephone office.
[0004]
Therefore, the following system has been proposed as a practical time signal audio supply system. That is, for each exchange, for example, a master time device having a highly accurate clock circuit using a crystal oscillator and a time signal sound supply device that generates a time signal sound based on time data from the master time device. Provide. Then, a reference time device is connected to each master time device through, for example, a telephone network or a dedicated line, and the time data of the master time device is calibrated with reference time data from the reference time device. .
[0005]
According to such a system configuration, the reference time device arranges the minimum necessary number in various places, and calibration based on the reference time data from the reference time device is performed, for example, several days through the telephone network or the dedicated line. By performing once, accurate time data can be obtained from the master time device. The master time unit can be configured at a relatively low cost using a crystal oscillator, and has a practical system configuration.
[0006]
[Problems to be solved by the invention]
By the way, in the hourly audio service, it is important to stably provide accurate time information to the user. Therefore, in the case of a time signal audio supply system using a clock circuit using a crystal oscillator in some of the devices as described above, it is possible to detect the deterioration of the crystal oscillator and the failure of the device at an early stage and take appropriate measures. It is important to make it.
[0007]
In the case of the system configuration described above, it is also important to take measures that can generate a time signal sound that avoids the influence of the deterioration of the crystal oscillator and the device failure in the master time device as much as possible.
[0008]
An object of the present invention is to provide a time signal sound supply device capable of satisfying the above requirements in a system using the master time device and the time signal sound supply device as described above.
[0009]
[Means for Solving the Problems]
In order to solve the above problems, in the invention of claim 1,
The time data from the master time device in which the time data is calibrated by accurate reference time information is received, and the internal time data having the same accuracy as the time data of the master time device is received, the time data from the received master time device. A time signal audio supply device that calibrates as necessary based on the internal time data generated from the calibrated internal time data, and sends the generated time signal sound to an exchange,
Error detection means for detecting an error between the time data from the master time device and the internal time data;
Error accumulating means for accumulating absolute values of errors detected by the error detecting means;
Means for emitting an alarm to the outside when the error value accumulated by the error accumulation means exceeds a predetermined value;
Means for detecting that a calibration operation has been performed in the master time device based on the time data received from the master time device, and calibrating the internal time data according to the received time data;
Accumulated error reset means for resetting the error accumulated by the error accumulation means at the time of calibration of the internal time data;
There is provided a time signal sound supply device characterized by comprising:
[0011]
In the invention of claim 2 ,
The time data from the master time device in which the time data is calibrated by accurate reference time information is received, and the internal time data having the same accuracy as the time data of the master time device is received, the time data from the received master time device. A time signal audio supply device that calibrates as necessary based on the internal time data generated from the calibrated internal time data, and sends the generated time signal sound to an exchange,
Error detection means for detecting an error between the time data from the master time device and the internal time data;
When the error detected by the error detection means is a minute error equal to or smaller than a first predetermined value that is determined in advance, the internal time data is not calibrated and the calibration operation is performed by the master time device. Means for calibrating the internal time data according to the received time data;
There is provided a time signal sound supply device characterized by comprising:
[0012]
Further, the invention of claim 3 is the invention of claim 2 ,
When the error detected by the error detecting means is larger than a second predetermined value that is larger than the first predetermined value, the time data from the master time device is ignored and only from the internal time data. There is provided a time signal sound supply device, characterized in that means for generating the time data for time signal sound and a means for issuing an alarm to the outside are provided.
[0013]
[Action]
In the first aspect of the present invention, the accumulated absolute value of the error between the time data from the master time device and the internal time data detected by the error detecting means is the time data of the master time device, the time signal sound Since the internal time data of the supply device has the same accuracy, an error (for example, deterioration of the crystal oscillator) generated in the time data generation unit of the master time device or an internal time data generation unit of the time signal audio supply device occurs. This indicates that the error (for example, deterioration of the crystal oscillator) has increased.
[0014]
In the first aspect of the invention, when the accumulated absolute value of the error exceeds a predetermined value, an alarm is issued to the outside. It is possible to detect the deterioration of the crystal oscillator caused by the above, and to take appropriate measures such as replacement of the crystal oscillator.
[0015]
According to the first aspect of the present invention, when the master time device is calibrated by a reference time device or the like, it is detected that the calibration operation has been performed, and the internal time data is calibrated. When the internal time data is calibrated, the error accumulated by the error accumulation means is reset.
[0016]
Therefore, according to the first aspect of the present invention, the internal time data can be calibrated in the time signal audio supply device in accordance with the calibration of the time data in the master time device, and the accumulated error is reset at the time of the calibration. Therefore, it is possible to correctly detect the deterioration of the crystal oscillator caused by the secular change or the like.
[0017]
Further, in claim 2 having the above-described configuration, the time data of the master time device and the internal time data of the time signal sound supply device have the same accuracy, and therefore, within the range of errors of each time data. If so, the internal time data can be accurately synchronized with the time data from the master time device. At this time, if the time data from the master time device is calibrated so as to synchronize the internal time data of the time signal audio supply device, the time data will also fluctuate.
[0018]
However, in the second aspect of the invention, when the error detected by the error detecting means is a minute error equal to or smaller than a first predetermined value set in advance, the internal time data is not calibrated and the time signal is kept as it is. Since it is used as the basis of voice, time signal data with less fluctuation can be transmitted.
[0019]
Further, in the invention of claim 3 , when the error between the internal time data of the time signal audio supply device and the time data from the master time device becomes large, the supply of the time signal sound is not immediately stopped. Ignoring the time data from the master time device, the self-running internal time data generator of the time signal sound supply device is generated, the time data for the time signal sound is generated only from the internal time data, and an alarm is sent to the outside. To emit. Therefore, it is possible to cope with a failure of the apparatus while supplying the timely sound.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Before describing the embodiment of the hourly sound supply apparatus according to the present invention, an outline of the entire hourly sound supply system will be described with reference to FIG.
[0021]
A reference time device 21 that generates highly accurate reference time data is provided connected to the telephone network 22. In FIG. 2, there is one reference time device 21, but usually a plurality of reference time devices 21 are provided to cover the whole of Japan.
[0022]
A master time device 24 and a time signal audio supply device 25 are provided for each of the exchanges 23 of each exchange.
[0023]
And the master time apparatus 24 produces | generates the time data for every second using the crystal oscillator whose oscillation frequency is 10 MHz, for example. Then, the master time device 24 supplies the generated time data to the exchange 23 as, for example, time data for charging, and also supplies time data (hereinafter referred to as “time data”) to the time signal sound supply device 25. This time data is referred to as master time data).
[0024]
The master time device 24 is connected to the telephone network 22, receives the reference time information from the reference time device 21 through the telephone network, and calibrates the time data. The reference time device 21 transmits the reference time data for calibration to each of the many master time devices 24 sequentially via the telephone network 22 at a rate of once every 1 to 7 days, for example. When receiving the reference time data, the master time device 24 calibrates the time data every second with a calibration width of 1 millisecond / second.
[0025]
That is, when there is an error between the reference time data and the master time data, the master time device 24 calibrates the master time data transmitted every second every 1 millisecond and synchronizes with the reference time data. Perform calibration. Therefore, the master time data changes by 1 millisecond until it becomes synchronized with the reference time data.
[0026]
The time signal audio supply device 25 has a built-in crystal oscillator with the same accuracy as the master time device 24, and uses the built-in crystal oscillator to create time data every second (hereinafter, this time data is referred to as internal time data). Then, an error between the internal time data and the master time data from the master time device 24 is detected, the magnitude of the detected error is determined, and the master time data is synchronized as necessary based on the determination result. Perform calibration. However, when the error between the two is a minute error within the allowable range of the crystal oscillator, the internal time data is not calibrated.
[0027]
Then, a time signal voice signal is generated by voice synthesis from the calibrated internal time data or the uncalibrated internal time data, and is supplied to the exchange 23.
[0028]
The time signal sound supply device 25 also detects the occurrence of an abnormality in the master time device 24 or the time signal sound supply device 25 at an early stage from the error between the internal time data and the master time data from the master time device 24. It has a function to send an alarm to the detection result. In the example of FIG. 2, the alarm is sent to the monitoring center 26 through the telephone network 22.
[0029]
Further, the time signal sound supply device 25 monitors the accuracy of the crystal oscillator built in the master time device 24 or the time signal sound supply device 25 based on the error between the internal time data and the master time data from the master time device 24. A function of detecting the deterioration of the accuracy of the crystal oscillator caused by the secular change or the like and alarming the outside when it is determined that the crystal oscillator has deteriorated is provided. In the example of FIG. 2, the alarm is sent to the monitoring center 26 through the telephone network 22.
[0030]
Furthermore, the time signal audio supply device 25 is calibrated by the master time device based on the reference time data from the reference time device based on the error between the internal time data and the master time data from the master time device 24. When the master time device is being calibrated, the time signal audio supply device 25 also performs a calibration operation to synchronize with the master time data.
[0031]
When the exchange 23 receives a request for issuing a time signal voice from the telephone terminal 27, the exchange 23 transmits the time signal sound from the time signal sound supply device 25 to the requesting telephone terminal.
[0032]
Next, as an embodiment of a time signal sound supply device according to the present invention, a time signal sound supply device 25 having the above functions will be described with reference to FIG. 1 and FIG. FIG. 1 is a block diagram illustrating a configuration example of the hourly sound supply device 25. FIG. 3 is a flowchart for explaining the operation of the hourly audio supply device 25.
[0033]
As shown in FIG. 1, the time input unit 1 receives master time information from the master time device 24 and sends it to the error detection unit 2. On the other hand, the time signal audio supply device 25 is provided with a crystal oscillator 8 having the same accuracy as the crystal oscillator of the master time device 24, and the internal time generator 9 is based on the oscillation output from the crystal oscillator 8 for 1 second. Each internal time data is created, and the created internal time data is sent to the error detector 2.
[0034]
The error detector 2 compares the master time data received from the time input unit 1 with the internal time data from the internal time generator 9 and detects the error ΔT. Then, the error detection unit 2 sends the detected error ΔT to the minute error determination unit 3 and the memory unit 6.
[0035]
The memory unit 6 has a function of accumulating and accumulating the absolute value of the error ΔT received from the error detection unit 2.
[0036]
The minute error determination unit 3 determines whether the error ΔT is a minute error equal to or less than a threshold θa that is included in the time considering the accuracy of the crystal oscillators of the master time device 24 and the hourly sound supply device 25 and includes the error. In this embodiment, θa = 100 microseconds.
[0037]
When the minute error determination unit 3 determines that the error ΔT is within a minute error range smaller than the threshold value θa, the minute error determination unit 3 instructs the time calibration unit 10 not to calibrate the internal time data. Upon receiving this instruction, the time calibration unit 10 sends an instruction not to perform time calibration to the internal time creation unit 9 and sends the internal time data from the internal time creation unit 9 to the speech synthesis unit 11. The voice synthesizer 11 generates a time signal voice based on the input time data and sends it to the exchange 23.
[0038]
As described above, in this embodiment, since the crystal oscillator of the master time device 24 and the crystal oscillator 8 of the hourly audio supply device 25 have the same accuracy, both crystal oscillators are operating normally. If the error is not large due to secular change or the like, the error between the master time data and the internal time data is always within a minute error range equal to or smaller than the threshold value θa.
[0039]
Therefore, at this time, if calibration is performed to synchronize the internal time data with the master time data, the operation causes the internal time data to follow the error included in the master time data, and the time data for the time signal fluctuates. On the other hand, as in this embodiment, when the error ΔT is equal to or smaller than the threshold value θa, calibration for synchronizing the internal time data with the master time data is not performed. Therefore, a time signal voice with little fluctuation is transmitted.
[0040]
Further, when the minute error determination unit 3 determines that the error ΔT is larger than the threshold θa, the minute error determination unit 3 does not give an instruction not to calibrate the internal time data to the time calibration unit 10, and uses the information of the error ΔT as master time data It is sent to the calibration determination unit 4.
[0041]
As described above, the master time device 24 calibrates the time at a rate of once every 1 to 7 days based on the reference time data from the reference time device 21. The master time data calibration determination unit 4 determines whether or not the received master time data is performing a calibration operation based on the reference time data from the reference time device 21 in the master time device 24.
[0042]
As described above, the calibration operation in the master time device 24 is sequentially performed for each master time data to be output, that is, every second, in units of 1 millisecond. Whether ΔT is a value in the range of 900 microseconds to 1.1 milliseconds (900 microseconds ≦ ΔT ≦ 1.1 milliseconds) in consideration of an error, for example. Judge whether or not.
[0043]
Note that whether or not the calibration operation in the master time device 24 is being executed may be determined based on whether or not only the error ΔT at a certain one second is within the above range. Considering that the operation is over a plurality of seconds, when the error detection unit 2 detects that the error ΔT per second is continuously within the above-mentioned range over a plurality of seconds, the calibration operation is being executed. May be determined.
[0044]
When the master time data calibration determination unit 4 determines that the calibration operation is being performed by the master time device 24, the master time data calibration unit 4 calibrates the internal time data to the time calibration unit 10 in synchronization with the calibration of the master time data. An instruction to perform the instruction is issued, and an instruction to clear the accumulated error is issued to the memory unit 6.
[0045]
The calibration instruction for the internal time data in synchronization with the calibration of the master time data, which is issued from the master time data calibration determination unit 4 to the time calibration unit 10, is a calibration instruction for each millisecond for each time data of 1 second. Therefore, the time calibration unit 10 issues this 1-millisecond calibration instruction to the internal time creation unit 9. In response to this, the internal time creation unit 9 calibrates the internal time data for the designated 1 millisecond by the next 1 second timing.
[0046]
Even during the calibration operation of the internal time data, the time calibration unit 10 sends the internal time data from the internal time generation unit 9 to the speech synthesizer 11, and the speech synthesizer 11 performs the time signal based on the internal time data. A voice is generated and sent to the exchange 23.
[0047]
When the above calibration operation is performed, the master time data from the master time device 24 and the internal time data of the time signal audio supply device 25 are completely synchronized. Therefore, the master time data calibration determination unit 4 issues an instruction to clear the accumulated error to the memory unit 6 during execution of the calibration operation. Upon receiving this clear instruction, the memory unit 6 resets the accumulated value of the absolute value of the error ΔT to zero.
[0048]
When the master time data calibration determination unit 4 determines from the information of the error ΔT received through the minute error determination unit 3 that the master time device 24 is not calibrating, the internal time data described above with respect to the time calibration unit 10 The error ΔT data is sent to the apparatus failure determination unit 5 without issuing a calibration instruction.
[0049]
The device failure determination unit 5 determines whether or not the value of the received error ΔT is large enough to determine that a failure has occurred in either or both of the master time device 24 and the time signal audio supply device 25. In this example, the apparatus failure determination unit 5 determines whether or not the error ΔT is larger than a predetermined threshold value θb. The threshold value θb is, for example, θb = 1.1 milliseconds.
[0050]
When the apparatus failure determination unit 5 determines that the error ΔT is equal to or less than the threshold value θb, it issues a calibration instruction to the time calibration unit 10 to synchronize with the master time data. Upon receiving this calibration instruction, the time calibration unit 10 sends to the internal time creation unit 9 a calibration instruction for synchronizing the internal time data with the master time data. Receiving this calibration instruction, the internal time creation unit 9 performs a process of calibrating the internal time data so as to eliminate the error ΔT from the master time data by the next 1 second timing.
[0051]
Also at this time, the time calibrating unit 10 sends the internal time data from the internal time generating unit 9 to the speech synthesizing unit 11, so that the speech synthesizing unit 11 generates a time signal speech based on the received internal time data, Send it to the exchange.
[0052]
When the apparatus failure determination unit 5 determines that the error ΔT is larger than the threshold value θb, the apparatus failure determination unit 5 determines that a failure has occurred in either or both of the master time device 24 and the time signal audio supply device 25, and time calibration is performed. The abnormality is notified to the unit 10 and the alarm sending unit 7.
[0053]
Upon receipt of the abnormality notification, the time calibration unit 10 ignores the subsequent master time data from the master time device 24, and the internal time creation unit 9 instructs the self-running only by the data from the crystal oscillator 8. Upon receiving the abnormality notification, the alarm sending unit 7 sends an abnormality notification indicating that an abnormality has occurred due to a failure in either or both of the master time device 24 and the time signal audio supply device 25 to the monitoring center 26. To send. Although not shown, the hourly sound supply device 25 itself is also provided with a buzzer and an alarm lamp, which also warn of the occurrence of an abnormality.
[0054]
By the way, the accuracy of a crystal oscillator generally deteriorates due to aging. In this embodiment, the change in accuracy of the crystal oscillator of the master time device 24 and the crystal oscillator 8 of the time signal audio supply device 25 is the cumulative value (error) of the absolute value of the error ΔT between the master time data and the internal time data. This error accumulation value is stored in the memory unit 6.
[0055]
In this embodiment, when the accumulated value of the error exceeds the predetermined threshold value θc, the memory unit 6 stores the crystal oscillator of the master time unit 24 or the hourly sound supply unit 25. It has a function of detecting that the crystal oscillator 8 has deteriorated and sending the fact to the monitoring center 26 through the alarm sending unit 7. In this embodiment, the threshold value θc is, for example, 250 milliseconds.
[0056]
When the crystal oscillator of the master time device 24 and the crystal oscillator 8 of the time signal audio supply device 25 are not deteriorated, the internal time data is calibrated so as to follow the master time data as described above. When calibrated, the internal time data is calibrated in synchronization with the master time data, and the error accumulated value of the memory unit 6 is cleared and reset to zero. Therefore, it is considered that the error accumulated value does not exceed the threshold value θc.
[0057]
However, if the accuracy of the crystal oscillator deteriorates, even if the internal time data is calibrated to the master time data, the absolute value of the error with respect to the time data per second increases, so the master time data is not calibrated. That is, before the error accumulated value of the memory unit 6 is reset to zero, the threshold value θc is exceeded.
[0058]
When the memory unit 6 detects that the accumulated error value exceeds the threshold θc, the alarm sending unit 7 is informed that the crystal oscillator of the master time device 24 or the crystal oscillator 8 of the hourly sound supply device 25 has deteriorated. To send. Upon receiving this instruction, the alarm sending unit 7 sends an alarm to that effect to the monitoring center 26.
[0059]
It should be noted that the time signal voice is not sent to the exchange 23 in an abnormal state in which an alarm is sent from the alarm sending unit 7 or in a state where the crystal oscillator is deteriorated. In response to this alarm, when the failure of the master time device 24 or the time signal sound supply device 25 is repaired and the crystal oscillator is replaced with a new one, the time signal sound supply device 25 again converts the time signal sound to the exchange. 23.
[0060]
The flow of the time calibration or the calibration operation and the abnormality detection operation in the time signal audio supply device 25 described above is shown in the flowchart of FIG. The flowchart of FIG. 3 corresponds to the processing operation when the time signal audio supply device 25 is realized using a microcomputer.
[0061]
That is, when master time data from the master time device is received (step S101), an error ΔT between the internal time data and the received master time data is detected (step S102). Then, the absolute value of the error ΔT is stored in the memory unit 6 (step S103). Next, it is determined whether or not the accumulated error accumulated in the memory unit 6 is larger than the threshold value θc (step S104).
[0062]
When it is determined in step S104 that the accumulated error accumulated in the memory unit 6 is larger than the threshold value θc, an alarm is sent to the outside such as the monitoring center 26 and the crystal oscillator of the master time unit 24 or the hourly sound supply unit 25. Is informed that the crystal oscillator 8 has deteriorated (step S105), and a treatment such as replacement of the crystal oscillator is awaited.
[0063]
When it is determined in step S104 that the accumulated error accumulated in the memory unit 6 is smaller than the threshold value θc, it is determined whether or not the error ΔT is a minute error smaller than the threshold value θa (step S106). If it is determined that the error is a slight error, the time calibration is not performed (step S107), the process returns to step S101, and the next master time data is awaited.
[0064]
If it is determined in step S106 that the error ΔT is larger than the threshold value θa, the master time device 24 determines whether calibration is being performed based on the reference time data (step S108).
[0065]
When the master time unit 24 determines that the time is being calibrated, a calibration operation is performed to match the internal time data with the master time data in units of 1 millisecond as described above (step S109). Then, the accumulated error in the memory unit 6 is cleared and the accumulated error value is reset to zero (step S110). And it returns to step S101 and waits for the arrival of the next master time data.
[0066]
If it is determined in step S108 that the master time device 24 is not performing time calibration, it is determined whether or not the error ΔT is larger than the threshold θb (step S111). When it is determined that the error ΔT is equal to or less than the threshold value θb, the internal time data is calibrated to match the master time data (step S112). And it returns to step S101 and waits for the arrival of the next master time data.
[0067]
If it is determined in step S111 that the error ΔT is greater than the threshold value θb, the subsequent master time data is ignored and the internal time data is generated based only on its own crystal oscillator (step S113). ), An abnormality is reported to the outside such as a monitoring center (step S114).
[0068]
As described above, in this embodiment, it is possible to determine the failure of the master time device or the hourly sound supply device while determining the deterioration of the crystal oscillator. Further, it is possible to detect a failure of the master time device or the time signal sound supply device while sending an accurate time signal sound.
[0069]
In addition, the time signal audio supply device does not always adjust the internal time data to the master time data from the master time device. When the error between the master time data and the internal time data is very small, the time adjustment is performed for the internal time data. Therefore, it is possible to suppress the fluctuation of the time signal voice that is the final output.
[0070]
【The invention's effect】
As described above, according to the present invention, a failure of the master time device or the time signal sound supply device is detected and an alarm is issued while sending an accurate time signal sound. Appropriate treatment can be performed. Further, since the failure is detected and the alarm is issued by detecting the deterioration of the crystal oscillator of the master time device or the time signal audio supply device, appropriate measures such as replacement of the crystal oscillator can be performed.
[0071]
Furthermore, it is possible to send a time signal voice with less fluctuation.
[Brief description of the drawings]
FIG. 1 is a block diagram of an embodiment of an hourly sound supply apparatus according to the present invention.
FIG. 2 is a diagram for explaining an overview of an entire time signal sound supply system to which a time signal sound supply device according to the present invention is applied;
FIG. 3 is a flowchart for explaining the operation of the embodiment of the hourly sound supply apparatus according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Time input part 2 Error detection part 3 Minute error judgment part 4 Master time data calibration judgment part 5 Device failure judgment part 6 Memory part 7 Alarm sending part 8 Crystal oscillator 9 Internal time preparation part 10 Time calibration part 11 Speech synthesis part

Claims (3)

The time data from the master time device in which the time data is calibrated by accurate reference time information is received, and the internal time data having the same accuracy as the time data of the master time device is received, the time data from the received master time device. A time signal audio supply device that calibrates as necessary based on the internal time data generated from the calibrated internal time data, and sends the generated time signal sound to an exchange,
Error detection means for detecting an error between the time data from the master time device and the internal time data;
Error accumulating means for accumulating absolute values of errors detected by the error detecting means;
Means for emitting an alarm to the outside when the error value accumulated by the error accumulation means exceeds a predetermined value;
Means for detecting that a calibration operation has been performed in the master time device based on the time data received from the master time device, and calibrating the internal time data according to the received time data;
Accumulated error reset means for resetting the error accumulated by the error accumulation means at the time of calibration of the internal time data;
A time signal audio supply device. The time data from the master time device in which the time data is calibrated by accurate reference time information is received, and the internal time data having the same accuracy as the time data of the master time device is received, the time data from the received master time device. A time signal audio supply device that calibrates as necessary based on the internal time data generated from the calibrated internal time data, and sends the generated time signal sound to an exchange,
Error detection means for detecting an error between the time data from the master time device and the internal time data;
When the error detected by the error detection means is a minute error equal to or smaller than a first predetermined value that is determined in advance, the internal time data is not calibrated and the calibration operation is performed by the master time device. Means for calibrating the internal time data according to the received time data;
A time signal audio supply device comprising: In the time signal audio | voice supply apparatus of Claim 2,
When the error detected by the error detecting means is larger than a second predetermined value that is larger than the first predetermined value, the time data from the master time device is ignored and only from the internal time data. A time signal sound supply device, characterized in that means for generating the time data for the time signal sound and generating a warning to the outside are provided.

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