Why does digital TV not show?
Systematic discontinuation of analog television broadcasting in favor of “digital” is in full swing. Digital TV is not only a high quality of transmitted picture and sound, but also a stable broadcast. However, sometimes problems with television all the same arise. As a consequence, the device does not pick up digital channels.
When you first turn on the STB the user sets the TV channels. Most of this process is carried out automatically. However, what to do if due to poor signal on the TV, you cannot tune the channels included in the two free multiplexes?
There can be several reasons. These are what we are going to talk about. Let’s carefully consider the main difficulties encountered by users to answer the question of why digital television does not show today. Here are some real arguments and effective ways to solve the problems.
Why doesn’t digital TV appear?
Often “no signal” message appears on the screen instead of a picture. Or the picture is scattered into many small squares.
- Your receiver or antenna doesn’t work.
- Carrying out repair work at the operator.
- External causes: weather deterioration.
- Smart TV firmware hasn’t been updated for a long time.
Let’s take a closer look at each of these causes. Also we’ll show you how to fix the problem.
The equipment is out of order
If your TV set has lost the signal of digital TV, then you mainly need to pay attention to the serviceability of the STB, antenna and connecting cables.
The easiest thing a user without knowledge of TV can do is to check the continuity of the cable from the TV to the antenna and set-top box. If the cable is damaged, the message “no signal” will appear on the screen. Carefully look through it and its connectors. If it is broken or kinked it is better to replace it with a new one.
If the cable is in excellent condition, look at the outside antenna. To receive a digital signal, it is important that it is in the shape of a “herringbone”.
It is recommended to direct it strictly towards the repeater. It is so important that even they advise to find out the angle of directivity with the help of compass or with the help of the program in your smartphone.
Antenna in the form of a “dish” may not receive a signal if there is a lot of dust or frost, ice coating on it. Then you need to remove it and clean.
The reason of signal disconnection may be a broken receiver. Usually inexpensive devices, serving to convert the signal and transmit it to the TV, often fail due to poor-quality components. How to check if the device is broken. If there is a second TV set in the house, you can connect the device to it. Or ask your neighbors to check their receiver on their TV. If after checking your receiver you are sure it is broken, you must buy a new one. As a rule, they can not be repaired.
Repair work at the operator
If the TV stops showing, there’s no need to rush to take it to the repair shop. Sometimes it happens during repair or maintenance work. Especially if you have satellite or cable television. These works on the channel are carried out with a certain frequency. You can find out about them in advance at the official website of your provider. Or call their technical support.
Often the receiver freezes with cable TV. In this case you need to reset the receiver. To do this, turn off the network for a while and then turn it on again.
If it only shows part of the channels
With partial display, the cause may be due to various reasons: hardware or software. After defining and eliminating them you need to setup the channels again. Usually first do the automatic, and if it does not lead to the desired result. manual.
To solve the problem, you need to figure out why the tuning is off. If it is possible, you need to repair or reconfigure. Then set the available channels. The automatic procedure requires less time and labor, but it does not always lead to success. In this case to return the channels resort to manual setting.
When not all the channels you want are available, you can do an automatic search procedure. To do this, just do the following:
- You need to turn on the TV and use the remote control to enter the settings menu.
- Among the available sections go to the one that relates to the settings of the receiver.
- They open the page for automatic channel selection and start the automatic scanning.
- It is necessary to wait a few minutes until the procedure is finished.
- After the automatic scanning is finished, it is necessary to save the results.
The user can, if he wants, arrange the channels as he wishes. After this procedure all available channels should be available. In the case where it was not possible to achieve the desired result, it is necessary to proceed to manual tuning.
Manual tuning of channels requires obtaining the necessary information in advance. You need to know the frequency at which the multiplexes are broadcasting, the modulation, as well as the speed of broadcasting. When the required information is obtained, you can directly proceed to the manual channel search procedure. To do this you need to take the following steps:
- Using the remote control you need to open the main menu.
- It opens the options section for using the receiver.
- Go to the manual channel tuning subsection.
- When you go to the manual tuning you need to enter the appropriate parameters and confirm them.
- Next, start the search. After finding the screen will show the strength of the received signal. If it is sufficient, you need to memorize the data and proceed to setting up the next signal.
Manual tuning requires more time, but in this case you can count on better quality of reception.
If careful tuning does not restore the display of all necessary channels, you need to make sure that the quality of the received signals is high enough and to check the serviceability of the antenna used.
Peculiarities of tuning of TV-receivers of some brands
The process of tuning the TV set can differ depending on the manufacturer. Although these differences are not very significant. over, as a rule, all devices have tips which make it easy to guess how to search for channels. But older models can only be adjusted manually. Below we explain the intricacies of this process on different TVs.
If you have a Samsung TV, go to menu, under “Channel” select the cable. Under “Country” enter four zeros and set the country. Under “Cable parameters” put: “Start frequency”. 298 000 KHz, “End frequency”. 362 000 KHz. Do not touch the rest. In the presetting select digital or analog. In the search mode, click on the network and wait until the picture appears. They can be removed from the list. To do this, go to “Channel Manager” under “Channels” and select the ones you want to delete.
If you have LG TV, go to menu or press “Home” button (for Smart-TV). In the options select your country, then click “Autosearch” in the settings. In the window that appears, select the type of signal. And then set the initial frequency data 274 000 KHz, the final. 770 000 KHz. Then start search. In the cable settings you can set the auto-update to run regularly without your intervention.
Owners of these devices need to go to “Settings” or “System settings” in “Settings”. In the item “Channel Tuning” select a digit. Then enter the values in the parameters, which are better to clarify with the operator.
Toshiba is configured in the same way as previous models. In the country settings select Germany, and the input. “Cable”. Then go down to automatic configuration and press OK. Select “DTV” mode in the opened window and set up parameters: start frequency. 274 000 KHz, end frequency. 770 000 KHz. Then confirm your choice and the configuration will start.
In older models setup is performed as follows: Press “Home” and select “Configuration”. Then go to “Settings” and select the channel setting. In the window that appears, select “Automatic settings”. Press “Reset” to save everything you find. Choose your country.
It is better to install the European countries, otherwise you will have to contact specialists to install the new software.
Then go to “Digital mode” and select the signal source cable. In the new window, click “Auto Search”. Then press “Start” and wait. Sometimes you may be prompted for a password. Try to enter four zeros, four ones or 1234.
In modern models, the setup process is slightly different. Select “Find Channels” in “Installation”, then “Re-install”. Specify country and select “DVB-C cable” in digital mode. Next, the device will ask you to enter the network frequency or baud rate. Then you will be prompted for 6.750. Then select “Fast” or “Full” search. In the first case, you will have to wait no more than 10 minutes, and in the second. about 30 minutes, but it will find more channels. If you do a quick search, you need to enter the value of the frequency difference. 8 MHz. If you search completely set QAM 256 and frequency 298,00.
Why does digital TV freeze?
Conventionally, the reasons that cause the loss of digital TV can be divided into 3 groups:
- Connecting Cable Problems. Most digital set-top boxes come with RSA wires, they are also called “tulips. They’re pretty unreliable over long periods of use and can fail over time. HDMI and SCART cables are more reliable in this regard. We also wrote about them in the channel tuning instructions.
- Antenna problem. In most of these situations, the culprit of errors and signal freezes, it is the antenna. People often come to us with this problem and we say once again that if your antenna has been catching analog channels, it does not mean that it will be able to do so with digital. About its correct choice and calculation under the digital, we wrote earlier here. In short, only say that the selection should be made depending on the remoteness of the main TV tower. For distances up to 7 km, ordinary indoor antennas with an amplifier will do. Everything above it should be caught by street antennas with an increased gain.
- Failures and prophylaxis at the station. Unfortunately, digital is still developing. Because of this, a number of stations may experience temporary interruptions or scheduled maintenance. We constantly write about them and notify subscribers. Work is often done to improve signal strength and increase the range of the transmitter. However, weather is often the cause of outages.
Thus, for most problems with hang-ups and lack of digital TV signal the receiving equipment is to blame. Therefore, before you call the hotline, you must make sure that all the actions on your part are done and the signal can be received and processed unhindered.
Defects in the TV
Usually they are relegated to the category of custom: a person did not do the initial setup correctly. Most often such a problem is observed at the stage of automatic channel search. Digital and cable programs are searched separately, so it is recommended to be attentive to the search parameters, and it is better to choose manual tuning.
To rule out such a variant, it is enough to check the possibility of connecting digital and cable programs. If the device does not find channels at all, the problem is in the socket. Do not try to repair it yourself: most often it ends with a complete failure of the device. Your TV will be repaired in no time.
Built-in adapter can fail as a result of physical damage, natural wear or frequent power surges. To replace it you need to intervene in the construction. This is not recommended to do without certain skills and theoretical background.
Important: if the tuner does not work in a new device, it could be a factory defect. We recommend you to contact the seller and to change the purchased equipment.
It is advised to update the tuner’s firmware and TV software at least once a year. If you do not do this, the equipment will stop catching the signal or will do it badly. The main thing is to download updates from the official site. Otherwise there is a risk to load a “pirated” version, installation of which will lead to the failure of the device.
Primary diagnostics and elimination of the simple causes of malfunctioning of your TV can be done by any user. Algorithm of actions to identify the problem:
- Examine the connectors, as well as the cables themselves for mechanical or physical damage.
- Check the TV receiver settings through the remote control and activate the desired playback mode with the AV/TV button.
- Check the operation of the receiver. If it does not work, the indicators are either not lit at all or lit in red. On a working set-top box the light bulbs will be green.
- Contact your ISP hotline and make sure there are no breaks or other damage on the line.
The antenna does not catch digital channels: reasons
To broadcast channels in digitized form, modern receivers are equipped with a built-in tuner. For older models it is sufficient to buy a set-top box. To date, there are several ways to receive digital channels:
- terrestrial, for the reception of which you can use an indoor or outdoor antenna, receiver;
- Cable, when the signal is transmitted to the TV through a connected cable from the provider’s internal server, which broadcasts TV;
- Satellite, when reception is carried out through a special antenna in the form of a dish.
If after starting the Autodetect function none of the channels appears on the TV screen, this can indicate a lack of signal, a wrong choice and connection of equipment, a fault in the settings or the receiver itself.
The lack of channels can be caused by the software malfunction. To decode a digital signal the tuner must operate according to a preset algorithm. If it is broken, audio or video information will not be played. To fix the problem, do one of the following.
- Before starting the auto search in the “Country” field set the “Other” option.
- Try to detect channels in “Manual” mode.
- Recapture the signal by resetting the built-in tuner or set-top box to factory settings, and then restart the auto search.
- If you use a device with pay TV channels, update the access card.
- Try to update firmware. The receiver software is outdated because it is no longer supported by the developer and as a result the search is performed incorrectly.
In practice, to reset the TV broadcasting involves the following steps.
- Connect the set-top box to the antenna or TV set;
- Serviceability check: After pressing “Menu” the factory tuner parameters should appear.
- Tune-up procedure. To do this, you need to enter the “Broadcasting” section (Channels, etc.).).
- Starting the Auto Scan. The order of the found channels is written into the memory of the device.
- If no results are available, the channel search is performed manually according to the receiver’s manual.
The problem is in the antenna
If no software failures were detected, the problem may be in the wrong choice or installation of the antenna, less often in the interference that clogs the reception channel. You usually need a DMV antenna to receive a digital signal. Using a MV or indoor antenna is not advisable, because in the absence of a good signal, the channels will disappear, or the image will become pixelated (crumbling into squares).
For users who do not live in megacities and large cities, it is worth buying an antenna with an active amplifier. It perfectly receives broadcasts and provides a steady image without stuttering and interference.
The following items should be considered when checking to see if the receiving device is properly installed.
- Digital antennas are extremely sensitive to the directionality of reception: often becomes critical a difference of several degrees. Therefore, in order for them to work reliably, when installing should be chosen in the direction of the satellite or repeater.
- If objects are between the tower and the antenna that are opaque to radio emissions, they can become a serious obstacle to free signal passage. This includes trees with dense crowns, brick and reinforced concrete buildings, metal roofs. Household electrical appliances can also interfere with a quality digital signal. Locate the antenna further away from them.
Problems in the cable
If after the manipulation with the antenna also failed, and the problem remains, it is worth checking the cable for twists, knots, deformations, damages. Sometimes it is chewed by pets.
It is advisable to “test” all wiring pins with a multimeter to rule out the presence of a break between the transmitting device and the receiver (TV). If the TV set has worked properly before, but during the tuning of digital channels stopped transmitting images and sound, you should check the serviceability of connectors, plugs, and sockets.
Malfunction of a set-top box
One of the reasons for the absence of digital TV channels can be a faulty tuner. Malfunction in the receiving device can be expressed in different ways:
In some situations you can observe the following picture:
All these points to a weak signal or no signal at all.
Specialists advise to unplug the receiver from the socket and connect it again after 5-8 minutes. If there are no results, it is worth checking for updates. If there are no new versions, you should think about the incompatibility of equipment or a malfunction that occurred in the electronic system of the tuner. To check if the set-top box is faulty, you can connect another device and rescan the channels.
Usually the manual describes in detail the tuning algorithm for television receivers after connection. If the tuning was in normal mode, and all channels were broadcasting normally, and then at one point disappeared, you should pay attention to changes in weather conditions.
Severe thunderstorm, heavy rain, hurricane wind, heat or frost can affect the broadcast of channels. There can be noted a decrease in quality or the complete absence of the image, loss or freeze sound, the appearance of thick “snow” on the TV screen.
If lightning hit the cable there can be a sudden jump in voltage and the formation of a static field, which negatively affects the operation of equipment and the quality of the perceived signal.
One of the factors, affecting the conductivity and characteristics of the signal, is an increased humidity. If such weather phenomena are detected, the TV should be turned off, and you should return to use it after a period of time. If you can’t restore the channels in the same mode and quality you should apply to a specialist.
There are many reasons why the TV set can’t find digital channels. You can fix the problem yourself: check the antenna, cable, and settings. If it does not work. turn to a TV wizard.
Hello! My name is Peter Gras and I’m the editor-in-chief of this portal. On this site our team tries to publish the most relevant and important information about various technologies in the world of digital television. Glad you stopped by, welcome!