Introduction
If you are a Headend Engineer. Then must be aware of that. Although role of a Headend Engg. is to run the STB properly in control room only. Rest of the things should be handled by field team.
But at some places a headend engg. needs to maintain the field also. It is seen in small sites only. While large companies have their own dedicated team for specific operations.
But a small knowledge of field makes a Headend Engg perfect. Which should be taken in a positive sense. Lets now come to topic.
Sometimes it have seen that in the headend STB is working fine. But when operator use this same stb at his own control room then it gets freezing.
Even sometimes at operator end it is working find. But at the customer end it is not working fine. It shows freezing at subscriber end.
Thus there can be various reasons behind freezing of a STB. So today in this article we will understand What Is STB Freezing ? & what are all these reasons through which STB gets freez ?
What Is STB Freezing Problem ?
When the video of STB get started to freez or pixels are misplaced in picture it represents the freezing of STB. It can occur at the starting of STB or after 5 to 10 minutes.
STB freezing can occur anywhere in the field or in the Headend too. It can be found in particular one STB or a group of STBs or even in all STBs. You need to check it step by step.
What Are Reasons Of STB Freezing And Their Solution ?
(1) RF Signal Level
This is the most common reason of freezing of a STB no matters what is the locations of your STB. It can be in Headend , at LCO end and subscriber end too.
If the input RF signal level of a STB is high or low then it will start freezing in channels. You always needs to maintain the input RF signal level of STB.
Then what should be input RF signal level of STB ?
Answer is,
It have seen practically that the Input RF signal level of STB should be around 40 to 60 db.Thus the signal below 40 db and above 60 db results freezing in STB.
Although it is little bit difficult to measure each and every frequency’s RF level in the field. But for accuracy point of view you need to do that.
Otherwise for your convenience you can only measure the Base frequency S21 or 306 MHz in the field for tuning your network. Which remove most of your tuning problems.
The one thing which we need notice here is that different STB manufacturer companies uses different tuner in it. Which have little bit different resistivity with RF signal.
(2) MER Level
MER Level is known as the Modulation Error Ratio. You need to maintain the MER Level in the Headend and LCO and Subscriber end too. You need to check it for each and every frequency (306 , 314 and 322 MHz etc.) of your network.
Now What Should Be MER Level For Each Frequency ?
Answer is,
It have seen practically that MER Level for each frequency in the control room and field should not go below 33. So MER Level above 33 is good for your network.
(3) Hardware Issue
Sometimes we see that after 5 to 10 Minutes of starting of STB our STB automatically started to freeze the channels. While it runs properly for 5 to 10 minutes. Why it happens ?
Answer is,
One or more than one on board component of STB gets failure to extreme heating. Then it started to freeze. This component can be anything like Power IC or Tuner IC or something elese.
You need to replace that component of STB to get rid of it.
(4) Other Issues
There can be some other issue too for freezing of channels in STB. These issues are general issues only like there can be losse connection of HDMI with TV , Loose RF connection and STB got hanged etc.
These issues can be resolved by simple troubleshooting like reset your STB or reboot your STB or plug out and plug in again HDMI cable etc.
Conclusion Of STB Freezing
The freezing in STB can be due to various reasons which we have explained above with its solutions.
Always try to maintain good signal level with good MER level. Also RF input signal level in the STB should be tested with RF professional meter only. Where we should not consider STBs own tuner display. Which shows in STB User Interface.
Because in some cases it is found that STB’s RF input reading in UI is not that much correct as meter shows. So always consider Professional RF Meter only to tune your network.
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Dear Sir,
How to viewed alll channels at singal screnn from directly data switch ?
Get direct cable from your data switch to laptop and put the multicast IPs into the VLC Media Player.
For reference consider this VLC Media Player Article
Also,
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