Sometimes there is no signal, what is the reason, why does the mobile phone sometimes have a signal,

1. There is no signal or the signal is relatively poor, mainly because the signal will be affected by various factors such as terrain, landform, and high-rise buildings in the process of propagation, such as the current location is in a relatively closed place, and the signal may be affected.

2. If the mobile phone signal of other China Unicom users is normal, the following methods can be used to troubleshoot:

Method 1] Turn on airplane mode, then turn off or restart your phone and try again.

Method 2] Test of changing the phone card to change the mobile phone card to the mobile phone of a family member or friend and try again.

Feedback, we will check and deal with it as soon as possible.

If you have an unstable or bad signal on your phone, it is recommended that you:

1.It may be that the signal coverage of your location is poor, and it is recommended that you restart your phone or try it in a different location.

3.If it doesn't work, please turn it off, take out the SIM card, and try to reinsert it.

4.Replace it with a different SIM card.

If the problem still exists after the above operation, it is recommended that you bring the purchase invoice, three-guarantee voucher and mobile phone to the local service center for testing by the engineer.

The main reason why the mobile phone sometimes has a signal and sometimes has no signal:

1.The signal of the bottom cell is poor.

The outdoor street has a good signal, and the indoor signal is poor, which is the most general situation, mainly caused by the surrounding buildings blocking the signal of the base station.

2.Large factories, villas with poor signal.

There is a good signal on the outdoor street, but there is basically no signal indoors, and the poor signal is due to the fact that the reinforced concrete in the room of the villa and the factory is difficult to be passed through by the mobile phone signal with a frequency of about 900MHz, which is blocked.

3.Rural Poor signal in the suburbs.

There is a weak signal outdoors, there is basically no signal indoors, and the poor signal is due to the fact that the base stations in the countryside and suburbs are not dense enough, and some places are far away from the base stations, resulting in weak signals.

4.Poor signal at the top level.

The reasons for the poor mobile phone signal of the high-level are different from the above points, in fact, the mobile phone signal of the high-level is not bad, so why is it still unreachable**? The main reason is that the upper floor can receive the signal from several nearby base stations, but because there is no blocking, the signal strength is about the same, so the mobile phone will frequently switch between several base stations, which is the so-called "ping pong" effect.

The mobile phone signal amplification device can solve these problems very well, as long as a set of mobile phone signal amplifier system is installed in a specific place, the mobile phone signal in the whole range can be used very well, bringing great convenience to the staff inside.

There is no signal on mobile phones because the signal will be affected by various factors such as terrain, landform, and tall buildings during the propagation process, and if you are in a relatively closed place, the signal will be affected. Here's how to deal with it:

1.Turn the phone back on and off to see if there is a signal;

2.Change the mobile phone card to a family member or friend's mobile phone and try again to see if there is a signal, if the mobile phone card is installed in other mobile phones and there is no signal, it may be a problem with the mobile phone card, you can replace a new card;

3.See if other users around have a signal, if other users have a signal, then it may be that your mobile phone is faulty, it is recommended to restore the factory value test, if there is still no signal, there may be a hardware failure can be detected and dealt with by after-sales.

Hello, your dormitory should have a lot of buildings fenced in, and the signal is transmitted there, so it can't be received. It's not that there is a problem with the IC of your mobile phone.@If that's the case, it's simple.,You can change the IC.,@ic which means a hardware for signal reception.

Are they all in the same place when there is no signal? Unicom? Move? Telecommunications? Other mobile phone cards of the same carrier have no signal? If so, then it's a signal environment problem, not a mobile phone problem.

Sometimes the baseband is not good, so try to re-brush the baseband.

Mobile phone communication is to send and receive signals through the network base station, and then communicate with the called party, such as the mobile phone shows no service may be related to the following conditions:

1. The SIM card of the mobile phone is in poor contact with the shneme of the mobile phone card slot, resulting in the failure of the SIM card circuit and the inability of the mobile phone to communicate with the network base station.

2. The mobile phone is incompatible with the system due to the application software for installation, resulting in the system software closing the modem in the mobile phone signal processing circuit, at this time you can turn off the mobile phone and then restart, the modem in the mobile phone signal circuit will be restarted, and after the signal is normal, delete the suspicious mobile phone application software installed before the problem.

3. The SIM card of the mobile phone is not registered in the network, at this time, you can insert this SIM card into another mobile phone, if it also shows no service as the reason for the SIM card.

4. If the SIM card of the mobile phone is accidental, and there is no signal in the network signal coverage area, it fails to reconnect to search the network and merge the book, at this time, you can manually search for network registration under the menu of Settings - General - Network - Network Operator.

5. If the signal coverage of the mobile phone SIM card network operator is not available, you can change the location to an open area, and then check the mobile phone signal grid display, if the display is normal after changing the location, you can call the network operator service ** for feedback and complaints.

6. **The card has been used for too long, and with a valid certificate, you can go to the local business hall to reapply for a card.

Machine signals come and go, and the possible reasons are as follows:

1. Mobile networks are susceptible to weather and electromagnetic interference, as well as signal shielding.

The quality of the G network is not good enough, the coverage is not large, and there are still some regions and provinces that do not have 4G networks.

3. The 4G signal is much better in the city center, and the Internet speed is normal, but the 4G network signal is much worse in the more remote areas.

4. In factories, monitoring rooms, trains, and in bad weather conditions, the 4G network signal is also much worse.

5. With the construction and development of 4G networks, these conditions will be improved.

There are only two situations when the mobile phone does not have a Huai code to guess the signal:

1. Network problems or network inability to cover.

When the network coverage is not good, it will appear that there is no signal or very weak when it is generally in mountainous areas, basements, elevators and when there is interference from shielded or letter lead models. In the process of debugging, optimization and maintenance, the network may also cause signal instability, and the general network will return to normal, and the mobile phone signal will return to normal.

2. Problems with the mobile phone itself.

There may be a problem with your phone's receiver. You need to go to the repair point to have a look.

Of course, the factor of SIM card corruption cannot be ruled out.

No signal"The error usually means that the TV is not receiving any valid signal. This could be due to one of the following reasons:

Electrical Channels are not set up correctly: Make sure that you have set the electrical Channels to the correct location and that you are using the correct input source. If you are using cables or satellite receivers, you should make sure they are connected and turned on.

Damaged TV antenna or receiver: Check to see if your TV antenna or receiver is damaged or needs to be replaced. You can try to reconnect or reinstall them, or replace them with a new one.

Weather Effects: Adverse weather conditions may cause signal interference or attenuation. In this case, be patient until the weather improves.

Other issues: If none of the above steps resolve the issue, check for other issues related to the portable device, such as the failure of the TV itself or the loose wiring connection. If you're not sure how to solve the problem, ask a professional for help.