With the National Radio and Television Bureau closing the original analog signal, forcing the popularization of set-top boxes, the number of digital TV users is increasing, and the problem of digital signal failure has begun to surface. According to the promotion and maintenance experience of the first-line in the past three years, the technicians of Jiadexi Electronics Co., Ltd. analyzed and summarized the common faults, and obtained some effective solutions to supply the hotel and hospitals to do the digital cable TV front-end renovation project. Peer reference.
A: The problem: the image output of the TV is not synchronized with the sound.
Solution: This kind of problem occurs. The general problem is in the set-top box, just start from the set-top box.
Two: Question: There is no signal output on some channels of TV
Solution: If you find a channel with no signal output, first find the corresponding set-top box and see if the signal light on the set-top box is on. If it is not lit, it will start from the set-top box.
Three: The problem: the TV signal is not good, there are snowflakes appearing
Solution: First check if there is any problem with the output line of the modulator. The main reason is to see if there is any insulator in the copper core inside the line connecting the modulator. Then check the floor splitter and the fixed trunk connected to the room. There is no problem. You can pass the paragraph test until you find the source of the signal interference. If there is a problem with the line, you can consider changing the frequency band of the modulator to solve some problems.
Four: Question: TV has images without sound or noise
solve:
1, the original sound, in a few days suddenly there is no sound but there are images, this situation is generally in the set-top box, the set-top box from the Kai can solve the problem.
2. Another is that there is no sound or noise after the installation. This situation is related to the sound system. Our product modulator is divided into two kinds of sound system "D / KI" system. In general, the default sound system of the TV set is D/K system, and the sound system of the modulator is I system. In time, you need to adjust the channel with no sound to the I system on the TV. Different TV semitone modes are different. The default of 6.5MHz-6.0MHz is 6.5MHz, which is the same as 6.0MHz. can.
Five: Question: Many TV shows show mosaic problems
Solution: The reason for the mosaic is mainly from the signal trunk. Most of the reasons are caused by the signal being too weak. Of course, it is too strong, because the set-top box has poor processing power for the signal source. In this case, Generally, it is called cable TV to adjust the strength of the backbone signal source or increase the amplifier at the local front end to solve the problem that the signal source is too weak, and increase the branch distributor to solve the problem that the signal is too strong. Six: Other: In the course of operation, the damage of related accessories is difficult to detect, such as dispensers, mixers and other accessories, according to the situation of the problem, the program that has problems, find out the cause and solve the cause.
Six, TV screen no program image
[Cause analysis] When this happens after the set-top box and the TV set up normally, there are three possibilities: (1) the RF input signal of the set-top box is too low or no signal, (2) the audio and video lines are not properly connected or the interface is damaged, ( 3) The TV conversion settings are not adjusted to the correct position.
[Case and Maintenance] When a resident of the Family School of the Municipal Public Security Bureau switched the TV to the function key, there was no image failure on the screen. The input level of the set-top box is measured, and the result is normal. The viewing sound and video line are connected, and the color is correctly connected according to the red, white and yellow colors. After careful inquiry, the user said that he had moved the set-top box and adjusted the audio and video lines. Since the TV has three lines of audio and video lines, the audio and video lines are transferred to another group and the fault is eliminated. After the detection, it was found that the original set of audio and video interfaces was bad.
Seven, individual channels appear mosaic
[Cause analysis] Mosaic appears on individual channels, indicating that the set-top box can receive TV signals normally, the system control circuit works normally, and the set channel parameters are also normal. The cause of this failure may be: (1) the signal is slightly weaker due to weather and geographical environment, and the receiving performance is degraded. {(2) The excessive signal quality of the connector is too good to cause bit error.
[Case and Exclusion] There is a user near Huazuyu, the digital TV signal is poor, and went to the maintenance to find the mosaic of "Car Fan" and "Kissing Baby" channel. Check the input signal level, the value is about 75dB, which is normal. It is normal to check the audio and video cable and the indoor cable connector. Then, the inspection is carried out along the entrance line, and finally the end of the interface between the brancher and the subscriber line is loose. Cut and redo the F joint. After the connection, the mosaic disappears and the fault is eliminated.
Eight, many channels appear mosaic
[Cause analysis] Errors are the main cause of mosaics. When the signal level is normal and the access device is normal, many channels appear mosaic. The possible reasons are: (1) the LNB power supply circuit in the set-top box is faulty; (2) the circuit in the Tuner in the set-top box is damaged, and (3) the system error occured. The biggest possibility is that the set-top box is faulty and cannot be decoded normally.
[Case and Maintenance] Most of the digital TV programs of a user on Xinhua Road have mosaics. Check that the indoor connector and signal level are normal, and no problems are found along the entrance line. It is preliminarily judged that the set-top box is faulty, and the fault is eliminated after replacing the same model set-top box. Open the original set-top box and find that the LNB power supply circuit inside the machine is damaged.
Nine, lack of channel programs
[Cause analysis] Digital TV lacks channel programs, mainly due to line problems. Such as poor indoor wiring, aging outdoor lines, or access line mismatch.
[Case and Maintenance] A resident of Tsinghua Court has normal reception of other programs, but there is no 1 to 12 sets of CCTV. Restore the original factory settings, re-search, still can not find the central station, check the set-top box access signal level is basically normal. Considering that the community is all newly laid, the outdoor signal should be no problem. Then open the wall terminal box to check, and found that this-5 cable has two joints, and together with the other two cables, seriously affecting the impedance matching. After consultation with the user, replace a national standard cable, and reduce the joints, and finally eliminate the fault, the user is also satisfied.
Ten, no sound on individual channels
[Cause analysis] There is no sound in the individual channel. The setting of the set-top box system is wrong. It is necessary to restore the factory settings and perform a re-search.
[Case and Maintenance] A resident of Hehuanyuan uses Konka set-top box, other channels are normal, but Jiangsu Satellite TV has no sound. Turn the volume of the TV and set-top box to the maximum and still have no sound. The mute button was not checked after checking. The initial suspicion is that the set-top box system is faulty. Then enter the factory password (000), restore the factory settings, exit and then conduct a full channel search until the search returns 100%, and finally the troubleshooting.
XI, crosstalk failure
[Cause analysis] There are two possibilities for crosstalk failure: one is co-channel interference, and the other is incorrect channel setting. In digital TV signals, the same frequency is very small, mainly the channel setting problem.
[Case and Maintenance] When there are users in the East Street of the East Street, there are always broadcast sound interference, and the crosstalk is very serious. The model of the set-top box is Huawei C2300. Since the frequency of Henan Satellite TV is far from the broadcast frequency band, it is impossible to generate co-channel interference, so it is suspected that it is a channel setting problem. Check the set-top box channel settings, find that the channel is set on the right channel or the mixed channel, and troubleshoot after adjusting the channel to the left channel. According to the author's experience, if you encounter crosstalk failure, you must first check the channel settings. If you still can't troubleshoot after changing the settings, you can remove one audio cable, that is, keep two audio and video cables.
Twelve, the smart card is invalid
[Cause analysis] When the TV screen is black and the "Smart card is invalid" prompts the fault, the main reason is that the card is not in good contact and the set-top box cannot correctly read the contents on the chip.
[Case and Repair] There is no screen after turning on the TV, and the words “Smart Card Invalid†appear. Check that the signal and cable connectors are normal. Exiting the search again will not solve the problem. Open the smart card panel on the front of the set-top box, and the fault disappears after the smart card is re-plugged. But soon the fault reappeared, and eventually the original set-top box (or smart card) was replaced to completely solve the problem.
Performance characteristics:
1, excellent anti-static lasting effect, the use of static black carbon fiber manufacturing,
2, dust-proof, moisture-proof, wear-resistant;
3,Smooth surface.
1,Base surface treatment;
2,Brush seal primer
3,Laying copper foils
4,Trowel coated epoxy conductive coating
5,Grinding, vacuuming
6,Roll coating anti static epoxy coating
A: The problem: the image output of the TV is not synchronized with the sound.
Solution: This kind of problem occurs. The general problem is in the set-top box, just start from the set-top box.
Two: Question: There is no signal output on some channels of TV
Solution: If you find a channel with no signal output, first find the corresponding set-top box and see if the signal light on the set-top box is on. If it is not lit, it will start from the set-top box.
Three: The problem: the TV signal is not good, there are snowflakes appearing
Solution: First check if there is any problem with the output line of the modulator. The main reason is to see if there is any insulator in the copper core inside the line connecting the modulator. Then check the floor splitter and the fixed trunk connected to the room. There is no problem. You can pass the paragraph test until you find the source of the signal interference. If there is a problem with the line, you can consider changing the frequency band of the modulator to solve some problems.
Four: Question: TV has images without sound or noise
solve:
1, the original sound, in a few days suddenly there is no sound but there are images, this situation is generally in the set-top box, the set-top box from the Kai can solve the problem.
2. Another is that there is no sound or noise after the installation. This situation is related to the sound system. Our product modulator is divided into two kinds of sound system "D / KI" system. In general, the default sound system of the TV set is D/K system, and the sound system of the modulator is I system. In time, you need to adjust the channel with no sound to the I system on the TV. Different TV semitone modes are different. The default of 6.5MHz-6.0MHz is 6.5MHz, which is the same as 6.0MHz. can.
Five: Question: Many TV shows show mosaic problems
Solution: The reason for the mosaic is mainly from the signal trunk. Most of the reasons are caused by the signal being too weak. Of course, it is too strong, because the set-top box has poor processing power for the signal source. In this case, Generally, it is called cable TV to adjust the strength of the backbone signal source or increase the amplifier at the local front end to solve the problem that the signal source is too weak, and increase the branch distributor to solve the problem that the signal is too strong. Six: Other: In the course of operation, the damage of related accessories is difficult to detect, such as dispensers, mixers and other accessories, according to the situation of the problem, the program that has problems, find out the cause and solve the cause.
Six, TV screen no program image
[Cause analysis] When this happens after the set-top box and the TV set up normally, there are three possibilities: (1) the RF input signal of the set-top box is too low or no signal, (2) the audio and video lines are not properly connected or the interface is damaged, ( 3) The TV conversion settings are not adjusted to the correct position.
[Case and Maintenance] When a resident of the Family School of the Municipal Public Security Bureau switched the TV to the function key, there was no image failure on the screen. The input level of the set-top box is measured, and the result is normal. The viewing sound and video line are connected, and the color is correctly connected according to the red, white and yellow colors. After careful inquiry, the user said that he had moved the set-top box and adjusted the audio and video lines. Since the TV has three lines of audio and video lines, the audio and video lines are transferred to another group and the fault is eliminated. After the detection, it was found that the original set of audio and video interfaces was bad.
Seven, individual channels appear mosaic
[Cause analysis] Mosaic appears on individual channels, indicating that the set-top box can receive TV signals normally, the system control circuit works normally, and the set channel parameters are also normal. The cause of this failure may be: (1) the signal is slightly weaker due to weather and geographical environment, and the receiving performance is degraded. {(2) The excessive signal quality of the connector is too good to cause bit error.
[Case and Exclusion] There is a user near Huazuyu, the digital TV signal is poor, and went to the maintenance to find the mosaic of "Car Fan" and "Kissing Baby" channel. Check the input signal level, the value is about 75dB, which is normal. It is normal to check the audio and video cable and the indoor cable connector. Then, the inspection is carried out along the entrance line, and finally the end of the interface between the brancher and the subscriber line is loose. Cut and redo the F joint. After the connection, the mosaic disappears and the fault is eliminated.
Eight, many channels appear mosaic
[Cause analysis] Errors are the main cause of mosaics. When the signal level is normal and the access device is normal, many channels appear mosaic. The possible reasons are: (1) the LNB power supply circuit in the set-top box is faulty; (2) the circuit in the Tuner in the set-top box is damaged, and (3) the system error occured. The biggest possibility is that the set-top box is faulty and cannot be decoded normally.
[Case and Maintenance] Most of the digital TV programs of a user on Xinhua Road have mosaics. Check that the indoor connector and signal level are normal, and no problems are found along the entrance line. It is preliminarily judged that the set-top box is faulty, and the fault is eliminated after replacing the same model set-top box. Open the original set-top box and find that the LNB power supply circuit inside the machine is damaged.
Nine, lack of channel programs
[Cause analysis] Digital TV lacks channel programs, mainly due to line problems. Such as poor indoor wiring, aging outdoor lines, or access line mismatch.
[Case and Maintenance] A resident of Tsinghua Court has normal reception of other programs, but there is no 1 to 12 sets of CCTV. Restore the original factory settings, re-search, still can not find the central station, check the set-top box access signal level is basically normal. Considering that the community is all newly laid, the outdoor signal should be no problem. Then open the wall terminal box to check, and found that this-5 cable has two joints, and together with the other two cables, seriously affecting the impedance matching. After consultation with the user, replace a national standard cable, and reduce the joints, and finally eliminate the fault, the user is also satisfied.
Ten, no sound on individual channels
[Cause analysis] There is no sound in the individual channel. The setting of the set-top box system is wrong. It is necessary to restore the factory settings and perform a re-search.
[Case and Maintenance] A resident of Hehuanyuan uses Konka set-top box, other channels are normal, but Jiangsu Satellite TV has no sound. Turn the volume of the TV and set-top box to the maximum and still have no sound. The mute button was not checked after checking. The initial suspicion is that the set-top box system is faulty. Then enter the factory password (000), restore the factory settings, exit and then conduct a full channel search until the search returns 100%, and finally the troubleshooting.
XI, crosstalk failure
[Cause analysis] There are two possibilities for crosstalk failure: one is co-channel interference, and the other is incorrect channel setting. In digital TV signals, the same frequency is very small, mainly the channel setting problem.
[Case and Maintenance] When there are users in the East Street of the East Street, there are always broadcast sound interference, and the crosstalk is very serious. The model of the set-top box is Huawei C2300. Since the frequency of Henan Satellite TV is far from the broadcast frequency band, it is impossible to generate co-channel interference, so it is suspected that it is a channel setting problem. Check the set-top box channel settings, find that the channel is set on the right channel or the mixed channel, and troubleshoot after adjusting the channel to the left channel. According to the author's experience, if you encounter crosstalk failure, you must first check the channel settings. If you still can't troubleshoot after changing the settings, you can remove one audio cable, that is, keep two audio and video cables.
Twelve, the smart card is invalid
[Cause analysis] When the TV screen is black and the "Smart card is invalid" prompts the fault, the main reason is that the card is not in good contact and the set-top box cannot correctly read the contents on the chip.
[Case and Repair] There is no screen after turning on the TV, and the words “Smart Card Invalid†appear. Check that the signal and cable connectors are normal. Exiting the search again will not solve the problem. Open the smart card panel on the front of the set-top box, and the fault disappears after the smart card is re-plugged. But soon the fault reappeared, and eventually the original set-top box (or smart card) was replaced to completely solve the problem.
Epoxy Anti - Static Level Coating
Scope of adaptation:
Walls, floors and storage tanks for all kinds of antistatic factories such as electronics, microelectronics, telecommunications, computers, precision instruments, textiles, printing, powders, chemicals, organic solvents.Performance characteristics:
1, excellent anti-static lasting effect, the use of static black carbon fiber manufacturing,
2, dust-proof, moisture-proof, wear-resistant;
3,Smooth surface.
Generally 5 years or more
1,Base surface treatment;
2,Brush seal primer
3,Laying copper foils
4,Trowel coated epoxy conductive coating
5,Grinding, vacuuming
6,Roll coating anti static epoxy coating
Technical index:
|
project |
index |
|
|
Drying time |
Table dry |
≤4 |
|
Hard work |
≤24 |
|
|
Adhesion (grade) |
≤I |
|
|
Pencil hardness |
≥2H |
|
|
Impact resistance |
40 Pass |
|
|
Flexibility |
3mm Pass |
|
|
Wear resistance(750g/500r,weightlessness,g) |
≤0.03 |
|
|
Water resistance |
48 hours no change |
|
|
Resistant to 10% sulfuric acid |
56 days no change |
|
|
Resistance to 10% sodium hydroxide |
56 days no change |
|
|
Gas-resistant, 120% " |
56 days no change |
|
|
Surface resistance |
105-108 |
|
|
Volume resistance |
105-108 |
|
Epoxy Anti - Static Level Coating
Epoxy Anti - Static Level Coating,Anti-Static Epoxy Topcoat,Epoxy Topcoat Material,Epoxy Finish Antistatic Material,Epoxy Antistatic Self-Leveling Floor
Jiangmen Kasole Building Materials Co., LTD. , https://www.kasole-paint.com