JPS6334381Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a system for detecting the occurrence of a disturbance that affects television reception radio waves.

Things that interfere with TV reception are:
There are those that occur constantly, such as ghost disturbances caused by buildings, and those that occur irregularly, such as fluttering disturbances, noise, and interference caused by aircraft and elevated vehicles.

Of these, it is relatively easy to understand the actual situation and implement countermeasures for the former type of failure that occurs constantly, but for the latter type of irregular failure, for example, when an aircraft or elevated vehicle passes by, as is clear from flutter failure. Because it involves both dynamic and temporal elements, it is difficult to understand the symptoms and severity of the disorder.

In other words, in the past, when such irregular failures occurred, equipment such as TV receivers, level meters, VTRs, and a large number of personnel were dispatched to the affected area, and the system was used to monitor the occurrence of fluctuations day and night. ,
The equipment is started and stopped manually after checking before and after the occurrence, which requires a huge amount of labor and equipment costs, is cumbersome to operate, and requires a long operating time for the equipment. The problem was that it was inefficient.

This invention was devised after repeated research in light of the above-mentioned circumstances, and its purpose is to automatically detect the severity and symptoms of TV interference that occurs irregularly, without any personnel, and to detect the occurrence of interference. detected at times,
Another object of the present invention is to provide a television radio wave interference occurrence detection system that can automatically control the operation of recording and measuring equipment in synchronization with the occurrence of a disturbance.

In order to achieve this objective, the present invention includes a variable filter for selecting fault occurrence information that receives the detection signal detected by the tuner from the received TV radio waves between the TV radio wave receiving antenna and the fault measurement and recording equipment. , a comparator that generates an activation signal when an amplitude fluctuation exceeding a reference bias is transmitted through the variable filter, and a time constant adjustment circuit that oscillates a predetermined drive signal in response to the activation signal from the comparator, and a time constant adjustment circuit provided therein. a monostable multi-oscillator that oscillates a stop signal after a set time elapses through the monostable multi-oscillator, a shaper that generates a control pulse signal from the drive signal and stop signal oscillated from the monostable multi-oscillator, and a control pulse signal from the shaper. A failure detection device is connected to a relay circuit that sends the error to the drive system of the failure measurement and recording equipment.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

Figure 1 shows an example in which the present invention is applied to detecting the occurrence of a flutter disturbance. 1 is a transmitting antenna, 2 is a receiving antenna, and 3 is a tuner connected to the receiving antenna 2, which detects the necessary detection signal from the received TV radio waves. Detect.

4 is a failure measurement and recording device, which is used in this example.
Although a VTR and recorder are used, the level D/U ratio,
Of course, a measuring device such as a flutter frequency measurement device may also be used. Reference numeral 5 denotes a fault occurrence detector according to the present invention, which is connected between the tuner 3 and the fault measuring and recording equipment 4.

When normal TV radio waves are disturbed by an aircraft or the like, the failure detector 5 detects the occurrence of a failure from the detection signal transmitted from the tuner 3, and instantly activates the failure measurement and recording equipment 4. It generates a stop signal as well as a drive signal for starting the motor, and its details are shown in FIG. 2.

That is, 6 is a variable filter for fault occurrence information selection connected to the tuner 3, which receives the detection signal output from the tuner 3, extracts frequency components and amplitude fluctuations specific to the fault, and inserts them into the comparator. In this embodiment, a bandpass filter is used as the variable filter 6 to detect a flutter disturbance, but a low-pass filter, a high-pass filter, etc. can be used depending on the type of disturbance such as noise or interference. A sensitivity adjuster 11 and an amplifier 12 are provided on the output side of the variable filter 6, and the sensitivity adjuster 11 allows the level fluctuation detection amount to be varied continuously from, for example, 1 dB to 10 dB.

A comparator 7 is connected to the variable filter 6 via an amplifier 12, and detects the detection signal transmitted from the variable filter 6, and detects when the amplitude fluctuation and frequency component are other than predetermined components that are a sign of failure. It waits in the off state, and generates an activation signal when the detected signal that is sent contains a precursor component of a failure occurrence.

Reference numeral 8 denotes a monostable multi-oscillator connected to the comparator 7, which is operated by a start signal from the comparator 7 and oscillates a predetermined drive signal. And this monostable multi oscillator 8
A time constant adjustment circuit 13 is provided, and when the operating time set in the time constant adjustment circuit 13 is reached, the monostable multi-oscillator 8 oscillates a predetermined stop signal.

Shapers 9 and 9' generate control pulse signals from the drive signal and stop signal oscillated by the monostable multi-oscillator 8. 10,
Reference numeral 10' denotes a relay circuit, which is connected to the drive system of the fault measurement and recording equipment 4, 4, and is connected to the drive system of the fault measurement and recording equipment 4, 4, and receives each control pulse signal obtained by the shaping devices 9, 9', that is, in this embodiment, a VTR drive signal, and a recording Sends meter operation signal, VTR stop signal, and recorder stop signal.

Since the present invention has the above-mentioned configuration, when investigating damage situations such as flutter failures, the failure occurrence detector 5 should be placed between the tuner 3 and the failure measurement and recording equipment 4 as shown in Figure 1. The level fluctuation detection amount is set in advance by the sensitivity adjuster 11, the operating time is set by the time constant adjustment circuit 13, and the measurement channel is selected by the tuner 3.

When set as above, the TV radio wave enters the tuner 3 from the receiving antenna 2, where it becomes a predetermined detection signal, and this detection signal is passed through the variable filter 6.
The signal is received by the comparator 7, and the reference bias is set in the comparator 7, resulting in a positive state.

When the received TV radio waves are normal, the comparator 7 is inactive, but if the received TV radio waves are affected by an interference such as an aircraft, and the level fluctuations and frequency changes occur due to changes in the high frequency phase, In response to this, the precursor component a as shown in Figure 3 A
A detected signal including the principal component b and the premature component c is input from the tuner 3 to the variable filter 6 over time.

Then, the variable filter 6 detects a preset fault-specific component of the frequency component of the precursor component a, for example, a 25 to 35 Hz component in the case of a flutter fault, and
Further, when the level fluctuation of the precursor component a exceeds the previously set reference level, the comparator 7 sends out an activation signal as shown in FIG. 3B.

Upon receiving this activation signal, the monostable multi-oscillator 8 oscillates a predetermined drive signal, and this drive signal is converted by the shaper 9 into a control pulse signal as shown in FIG. The relay 10 operates in synchronization with the generation of the waveform,
A drive signal as shown in FIG. 3D is applied to the drive system of the fault measuring and recording equipment 4, and the VTR and recorder are activated instantly.

In this way, recording and recording of the fault situation is automatically started in synchronization with the occurrence of the fault, and when the precursor component a, the main component b, and the premature component c are recorded, the time constant adjustment circuit 13 activates the monostable multi-oscillator 8.
A predetermined stop signal is oscillated from the stop signal, which is converted into a control pulse signal (FIG. 3(e)) by the shaper 9'.
In synchronization with the generation of the rising waveform of this control pulse signal, the relay 10' applies a drive signal as shown in Figure 3 to the drive system of the fault measurement and recording equipment 4, thereby stopping the operation of the VTR and recorder. .

According to the present invention described above, the occurrence of irregular TV signal disturbances such as flutter disturbances is detected, and each device for recording, recording, and measurement is automatically activated in synchronization with the occurrence of the disturbance. Furthermore, the operation of each of the devices can be stopped in synchronization with the disappearance of the fault. This makes it possible to accurately assess the extent and symptoms of TV interference without any personnel, and to measure only the time during which the interference is occurring.
It is efficient because it operates the recording equipment, and has the excellent effect of significantly reducing costs and manpower required to identify failures.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing an example of a system for detecting the occurrence of a disturbance that affects received TV radio waves according to the present invention, Fig. 2 is a block diagram showing an example of a fault occurrence detector according to the present invention, and Figs. F is an operation waveform diagram of each part of the present invention. 3... Tuner, 4... Fault measurement and recording equipment, 6... Variable filter, 7... Comparator,
8... Monostable multi-oscillator, 9,9'...
...Molder, 10,10'...Relay circuit, 13...
...Time constant adjustment circuit.

Claims (1)

[Scope of utility model registration request] A variable filter 6 for selecting failure occurrence information receives a detection signal detected by a tuner from received television radio waves, and generates an activation signal when an amplitude variation exceeding a reference bias is transmitted through the variable filter 6. A comparator 7 and a time constant adjustment circuit 13 that oscillates a predetermined drive signal based on the activation signal from the comparator 7 and is also provided.
a monostable multi-oscillator 8 that oscillates a stop signal after a set time has elapsed via the monostable multi-oscillator 8; a shaper 9 that generates a control pulse signal from the drive signal and stop signal oscillated from the monostable multi-oscillator 8;
9', and relay circuits 10 and 10' that send control pulse signals from the shapers 9 and 9' to the drive system of the fault measurement and recording equipment 4, and between the TV radio wave receiving antenna and the fault measurement and recording equipment. A system for detecting the occurrence of a disturbance affecting television reception radio waves, characterized in that the system is connected to a television reception radio wave.