What is a Long Range Cordless Phone?

The telephone remote controller is one of the remote power controllers. It transmits control information through the telephone program-controlled exchange network to control the power on and off of the device. specialty. It can also carry out secondary development according to the needs of users. It will form a series of products in continuous improvement to meet the needs of different users and different occasions. It is generally used for industrial control. ^[1]

The 21st century is the information age, and various new telecommunication technologies have promoted the progress of human civilization. Since the invention of the telephone by Alexander Graham Bell in 1876, telephone networks in countries around the world have grown rapidly.

In the past ten years, China's fixed telephone business has shown rapid growth worldwide. In August 1997, the total capacity of office telephone exchanges exceeded 100 million, and the network scale ranked second in the world. In July 1999, the total number of fixed telephone users exceeded 300 million.

The modern telephone network is composed of switches and telephone transmission lines. Its performance has made great progress and its reliability is very high.

Remote control technology uses a certain means to control a certain distance of the controlled object. Common methods include radio remote control, wired remote control, infrared and ultrasonic remote control. Radio remote control is the use of radio signals to implement remote control of controlled objects. Radio remote control must inevitably occupy certain radio frequency resources, causing electromagnetic pollution; conventional wired remote control requires special wiring, which increases investment; while infrared and ultrasonic remote control are limited by distance. Among the existing remote control methods, there are also a carrier communication control method and a wireless paging-based remote control method. The carrier method is to transmit information through a power line. This method is limited to the same substation and the same transformer. Therefore, there is also a distance problem, and the application range is limited; the remote control method based on wireless paging utilizes the existing paging frequency resources without occupying additional frequency spectrum. Moreover, with the nationwide networking of the paging network, its remote control distance is basically unlimited. However, the controlled party's action lags behind the controlling party's operation in this way, does not have real-time performance, and does not have high reliability.

As a new control method, the telephone remote control shows certain advantages compared with the conventional remote control method. It does not need special wiring, does not occupy radio frequency resources, and avoids electromagnetic pollution. At the same time, because the telephone lines are networked in different places, the existing telephone network can be fully utilized, so the remote control distance can be across provinces and cities, and even across countries. ^[2]

(1) Principle block diagram.

Telephone remote control system to

Take HH501 telephone remote controller as an example.

Computer network equipment startup and shutdown

Big screen startup and shutdown

Radio transmission tower equipment control

Water tower pump control

Industrial equipment remote control

High security phone lock

Security video surveillance equipment control

Start and stop control of cable TV equipment

1. What is the phone controller?

Answer: The control information is transmitted through the telephone program-controlled exchange network to control the equipment on and off. For example, HH501 telephone remote controller, it has three power sockets for three electrical equipment. Access it remotely by dialing a phone or cell phone and manipulating it. Thereby, the electrical equipment is switched on and off. You can also check its working status at any time.

2. What power source can I control?

Answer: 220v AC power; with little modification can also control DC 12V, 48V, etc .; or control higher voltage equipment through contactors, such as: 380V, 6KV, 10KV ...

3. How to use it?

Answer: First insert the phone line to connect with the phone according to the instructions, turn on the power, and then dial the phone or mobile phone to guide the operation through voice guidance. Before this, you can press this control button for local trial operation.

4. Can the mobile phone be used?

Answer: Any mobile phone or landline phone in the world can be used.

5. What is the power?

Self-power consumption is less than 3W. The power consumption of a single power socket is 1100VA, and the total power consumption is 2200VA.

8. Where can it be used?

A: It is used for the start and stop of electrical appliances, such as: computers, routers, satellite receivers, start and stop of telephone base stations, unattended computer rooms, LED screen start and stop, remote street light management, aviation, aerospace, military equipment, ... ....,,Wide range of applications.

9. Can it be turned off and on automatically?

Answer: If needed, it can be solved by a delay circuit.

10. What is local control?

Answer: Use the local phone connected to the controller to directly control the appliances. The local control can also set parameters such as password, ringtone number and tie-in time.

11. Why does the controller ring for 5 times and the phone does not go off-hook automatically?

A: The phone is transferred, or the number of rings is less than the number of rings.

12. Can I query the current status?

Answer: Yes. Through a simple query, you can know whether the power is on or off.

13. Can I change my password?

Answer: Yes. Set by the local control button.

14. Can I set the number of rings?

Answer: Yes. Set by the local control button.

15. Does it affect the original telephone use?

Answer: Does not affect

16. Can I modify my own voice? Or change to English tone?

Answer: No. Because the voice is solidified in the chip. Any language can be re-solidified on demand.

17. Can it be used where there is no telephone line?

Answer: As long as there is a place where mobile phones can communicate, you can increase the use of mobile phone receiving equipment.

18. What's going on when there is sound inside when the power is first connected?

Answer: The relay sounds normal, or the weak AC sound does not affect normal work.

19. What other application functions?

A: You can monitor the voice.

The remote controller of the telephone mainly receives the information of controlling the household appliances uploaded from the telephone line, and sends the instructions of controlling the household appliances to the intelligent controller through parallel communication after decoding; it receives the alarm or help information (via parallel communication) from the intelligent controller, and automatically After dialing (can be preset by the keyboard), the information is transmitted to the user in voice form or the alarm is directly issued. ^[4]

The purpose of developing telephone remote controller is to realize the telephone control of household appliances, so as to realize the automatic control of electrical appliances and industrial equipment, especially dangerous industrial equipment. At the same time, it can better save a lot of time for busy people and devote themselves to work. Therefore, the control system will achieve the following functions:

1. Voice prompt function module. This module mainly implements the prompt function for online status query and operation, and realizes the prompt operation through the ringing circuit.

2. Automatically off-hook. This module will realize the function of automatic off-hook. When the call comes in, the system will automatically check the ring tone and count. When the time comes, the system will automatically off-hook. ^[2]

3. Password verification. This module mainly implements password verification. When the system is off-hook, the system will give a tone and ask for a password. When the password is entered correctly, the system will start to work; if the password is entered incorrectly, the system will hang up.

4. Change the password online. The user can modify the system password according to the prompt tone, and a 5-digit password can be set.

5, dual audio signal decoding. Decode the audio of the phone, this module is completed by the chip MT8870.

6. Control electrical switches. This part includes manual control and telephone control, which can be used to control the switching of electrical appliances.

7, electrical status inquiry. The telephone access mode can be used to query the status of the appliance and determine whether the appliance is in the working state or the standby state.

8. Busy tone detection. This function has this function for every telephone, and busy tone can also be detected in this system. ^[2]