Tata Sky DTH Service in Rains

[Karan]

I have read about many people here getting loss of signal when it rains. I too personally experienced it a few days back and decided to investigate. Here is what i found:

Since Tata Sky broadcasts over the Ku band, it is common for the signal to over this band to experience what is called Rain Fade or rain attenuation. Thankfully as the link suggests there are measures to overcome this, which i think Tata Sky does use.

 

[netfreak]

Water is bad for all radio signals. Out bodies are effectively bags of water. Thats why it you run ping --ip-of-WiFi-router-- -t and keep it running you can see increase in latency if you stand between AP and PC.

 

[Karan]

Well if you stood between your Dish and the satellite then you would not get any signal, line of sight. I only mentioned the above because it turned out to be a common occurrence for the Ku Band.

 

[vasanthallies]

After the Mumbai viewers facing the persistent disruptions due to the recent heavy showers, now Delhiites are next in line. The next time your TV set flickers during a downpour, peer out of your window and check if the raindrops are in extra-large sizes.

The bigger the raindrops, the greater the chance of a blank screen for a few seconds or minutes. Though, the technology is designed on a 99.7 per cent probability that direct-to-home (DTH) signals will be received despite rainfall, which amounts to the signal disruption probable only a total of four hours per year for India, an Six Sigma approach.

Monsoons have officially arrived in Delhi, but the Weather Forecast department say it will take a few more days to rain heavily, the time when DTH services are most vulnerable to disruptions. When Mumbai received over 500 mm of rainfall in a day recently (including Santacruz and Colaba weather stations), DTH subscribers across suburbs fidgeted with TV sets, many complaining of poor signals.

Just like one needs a threshold level of light to observe an object, DTH receivers like set-top boxes or antennae need a certain level of signals to detect a programme. DTH signals depend on very high frequency electromagnetic waves and big raindrops scatter these electromagnetic waves, so less energy is received by the antenna and programme viewing is disrupted temporarily.

In Delhi, DTH transmission was temporarily disrupted due to thunderstorms and showers on quite a few occasions in the last few months. Unlike raindrops, fog, winds and clouds cause little or no effect on signals.

"Climatologically speaking, sustained heavy downpour like Mumbai generally does not happen in Delhi. However, it is possible that some days receive torrential downpour here against the set pattern," said India Meteorological Department's spokesman B.E Yaday.

A Tata Sky spokesperson said their signal availability is designed to exceed the global standard of 99 per cent. "In rare cases, when the size of the rain droplet is too big, the DTH signal could fade. Typically, it will be restored on its own within a few minutes."

Monsoon arrives in Delhi with Cable troubles | Televisionpoint.com News

 

[hitman]

I think its raining lightly now for 2-3 days ... Still no probs faced... Lets wait and see wht's the situtation whenever there's a heavy downpour...

 

[cyberwiz]

Yup disruption due to rain is an inherent problem with the technology..here's another article on the same issue published in yesterday's (i.e. 4.07.07) Times of India, Delhi edition

Direct-to-home rain disruptions in city
TIMES NEWS NETWORK

New Delhi: With the monsoons having hit Delhi, directto-home (DTH) subscribers have started complaining about blackouts while watching TV. Keeping consumers’ interests in mind, TRAI is coming up with a set of guidelines for the DTH players to follow, pertaining to their quality standards. These guidelines will be applicable soon and is likely to ensure that consumers will get better reception of channels.
While Delhiites might have to deal with the problem of poor reception of channels for only a few minutes, unlike Mumbai, where the problem is much more persistent due to heavier rainfalls, the fault, according to TRAI sources, is inherent in the system. The DTH operators use KU band frequency for transmission of television channels to subscribers that get affected during rains and thunderstorms. Said a source: ‘‘We are in the process of finalising the guidelines pertaining to DTH as many more players have entered the field.’’ With the proposal of extending CAS to the rest of Delhi being considered by the ministry of information and broadcasting, the need to streamline it is also being felt by the authority.
Meanwhile, the companies providing DTH services claim that the technology is designed on a 99.7% probability that the DTH signal will be received despite rainfall. ‘‘Our engineers are doing pre-monsoon checks to ensure that signals are received properly,’’ said a spokesperson of Tata Sky. Tata Sky’s service has been designed to provide signal availability exceeding 99%, which is in line with international standards. This is significantly better than the service reliability offered by most utilities including electricity or mobile telephony.’’ He added: ‘‘In rare cases, when the rainfall becomes very heavy the DTH signal could fade but it comes back on its own within a few minutes.’’ Sources in Dish TV also claimed to be taking all precautionary measures and better technology is being used by the company to take care of the problems faced by consumers during rains.
The problem with DTH arises as the system needs a certain level of signals to receive a programme. These signals depend on very high frequency electromagnetic waves which get scattered by heavy rainfall. This results in less energy being received by the antenna, causing temporary loss of programme reception.

 

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[nighthawk]

Could anyone tell me if this disruption occurs even if you have a larger (90mm) dish ?

 

[vasanthallies]

Yes u r right....If the dish size is big then u wont have signal scrambling.I have seen this at my uncles house. He has Tata Sky and he hasremoved the dish given by the company and has used the dish that are beeinginstalled on a ATM centers. I thinmk u get it........The ATM dish LNB will communicate dually... but what he did was removed the LNB and he fitted it with KU band LNB given tatasky. The surprise was that KU band LNB is perfectly fitting on the ATM dish..Now even in heavy rain he was able to get 90% signal. The more advantage was that the signal mostly is in 100% in both the readings. Also the audio quality is really superior.....

 

[nighthawk]

how big is this dish ? is it bigger than 90cm ?

 

[inetbum]

99.7 % working rate and disruption for only a few minutes? Right now raining heavily and all my signals show 0 and screen is blank for the past 10 minutes.