Ubc In The Rain.

[Ned]

It's an old topic I know but maybe in the meantime someone has come up with a way to overcome the UBC wet season blues. I rent the equipment but I'd be prepared to buy a bigger dish if this would stop the signal from disappearing during heavy rain. I've been told that a bigger dish wouldn't do any good as it would be incompatible with the other UBC equipment. Is this right?

Any ideas?

[johng]

I've been told that a bigger dish wouldn't do any good

What a load of cods wollop !!!

Yes of course a bigger dish will help... the bigger the better,however you would probably be buying a prime focus dish ( as apposed to the UBC offset dish ) so you may have some trouble mounting the LNB in the correct position.

You must also check that the dish will cope with KU band signals, a lot of bigger dishes sold here are for C band reception and may not work well with the higher frequency that UBC uses.

While you're at it ( if you have the space or the big dish ) why not get a "proper" satellite reciever and motorised dish and save a lot of money on the UBC subscription ?..

http://satellite.information.in.th/

http://www.satthai.tv/satellite_n/sat_product.html

Edited July 3, 2006 by johng

[Firefoxx]

I wasn't using UBC, but IPStar, and had a pretty big dish... it was about 2M tall. It still petered out when it rained. However, the tiny UBC dish peters out even when it's cloudy...

All-sat programming is good in one way, but a lot of people still prefer the programming on UBC (even though it's nowhere near the stuff on US cable).

[astral]

I am sure a bigger dish will help.

I reckoned that I needed a 1.2m dish, but never got round to fitting one

to prove the point to UBC.

This will give 4X the signal (6db) over the standard 60cm.

The dish should be solid, not a perforated C band dish and I suggest you buy a new LNB.

Then you can leave the UBC dish in tact, and they cannot complain that you have modifed their equipment.

Ipstar is a little different as you are transmitting as well as receiving.

[h90]

Ipstar is a little different as you are transmitting as well as receiving.

The main difference is that IPStar never works properly neither with big nor small dish.

[monty]

I've seen UBC use two sizes of dishes, a 60 cm and an 80 cm dish...

The 60 cm dish is most definately not good during rain... Try to get then to put an 80 cm dish if you have the small one...

Another option is to get a better LNB (the receiving head to wich the cable is connected). The UBC ones are generic (cheap) units generating a lot of noise. A high end LNB, as used by satellite amateurs to receive weak signals, will definately improve reception in a big way, is easy to install and no realignment of the dish is needed...

[PMK]

Hey John,

Do you have any idea how old the info is on that first link?

Peter

I've been told that a bigger dish wouldn't do any good

What a load of cods wollop !!!

Yes of course a bigger dish will help... the bigger the better,however you would probably be buying a prime focus dish ( as apposed to the UBC offset dish ) so you may have some trouble mounting the LNB in the correct position.

You must also check that the dish will cope with KU band signals, a lot of bigger dishes sold here are for C band reception and may not work well with the higher frequency that UBC uses.

While you're at it ( if you have the space or the big dish ) why not get a "proper" satellite reciever and motorised dish and save a lot of money on the UBC subscription ?..

http://satellite.information.in.th/

http://www.satthai.tv/satellite_n/sat_product.html

[johng]

Do you have any idea how old the info is on that first link?

Ok its quite old I'm sure there are many much more upto date sites for any one with the time to search them out.

[Ned]

Speaking to a guy yesterday who was involved with LNB production in China and he reckons it wouldn't be worth your while to either upgrade the LNB or get a bigger dish. The problem he reckons is the lack of power of the transmission and any improvements would only be slight and not worth the expense.

The old satellite Thaicom 3 I understand has been replaced by Thaicom 5. I know it's been launched already but is it in operation yet? Maybe the signal from it might be stronger?

[johng]

Speaking to a guy yesterday who was involved with LNB production in China and he reckons it wouldn't be worth your while to either upgrade the LNB or get a bigger dish

The rules of physics say otherwise

Yes of course the signal is weak..its had to travel 36,000 kilometers and was only 50 (ish) watts strength to start with when it left the satellite.

How about this for an analogy .. imagine its raining ( rain being satellite signal ) you go outside with a tea cup ( your UBC dish ) and a washing basin ( a bigger dish) which of the two would collect more rain ?

[The Coder]

Rain outages are something I don't quite understand. In the USA I had DirecTV and it never, ever went out even one time no matter the weather. It uses a small dish and was the type thing you setup and forget because it just worked every single day. Dunno why anytime they implement technology in Thailand it just doesn't seem to ever work right. But I just don't understand how they managed to screw this one up. Is it the "tuk tuk" of satellites up there or what?

[astral]

I researched this some time ago. Apparently it has to do with where you live.

In the higher latitudes the rain drops are much smaller than in the tropics.

“For C-band it (rain) is not as critical, in regards to Ku-band, however, the diameter of a rain drop is definitely detrimental to passage of Ku/Ka-band signals. In the above referred to Houston storm, Ku was down a grade in video quality whereas here in Mexico it was wiped out completely - and I have top grade Ku video reception on clear days here in Mexico and top grade Ku equipment. In regards to diameter of the raindrop, signal attenuation is proportional to the wavelength of signal frequency and the size of the raindrop through which the signal has to pass. Transmissions at C-band have a longer wavelength than transmissions at Ku band, and are therefore less susceptible to rain attenuation. For example, a C-band frequency has a wave-length of approximately 7 cm, and a Ku-band frequency has a wavelength of approximately 2 cm. Any raindrop in the path of either signal which approached half the wavelength in diameter, will cause attenuation. It is to be noted, Ku-band attenuation in rain is approximately nine times that of C-band or 9:1dB - for each one dB loss in C-band expect nines times that on Ku (remember that each 3dB signal loss is a halving in power). Note rain attenuation effect on Ku-band with change in dish look angle - the conclusion being that there is less loss at greater look (elevation) angles”.

Sorry I do not have the url for this any longer

The rain in Thailand tends to be tropical in nature with large drop sizes, hence the greater attenuation. The position of Thaicom at 77°E means a relatively low angle for the dish as we are located at 101ºE. The combination of these factors means that a larger dish size is required to receive, (and transmit) signals in heavy rain conditions.

[astral]

I researched this some time ago. Apparently it has to do with where you live.

In the higher latitudes the rain drops are much smaller than in the tropics.

“For C-band it (rain) is not as critical, in regards to Ku-band, however, the diameter of a rain drop is definitely detrimental to passage of Ku/Ka-band signals. In the above referred to Houston storm, Ku was down a grade in video quality whereas here in Mexico it was wiped out completely - and I have top grade Ku video reception on clear days here in Mexico and top grade Ku equipment. In regards to diameter of the raindrop, signal attenuation is proportional to the wavelength of signal frequency and the size of the raindrop through which the signal has to pass. Transmissions at C-band have a longer wavelength than transmissions at Ku band, and are therefore less susceptible to rain attenuation. For example, a C-band frequency has a wave-length of approximately 7 cm, and a Ku-band frequency has a wavelength of approximately 2 cm. Any raindrop in the path of either signal which approached half the wavelength in diameter, will cause attenuation. It is to be noted, Ku-band attenuation in rain is approximately nine times that of C-band or 9:1dB - for each one dB loss in C-band expect nines times that on Ku (remember that each 3dB signal loss is a halving in power). Note rain attenuation effect on Ku-band with change in dish look angle - the conclusion being that there is less loss at greater look (elevation) angles”.

Sorry I do not have the url for this any longer

The rain in Thailand tends to be tropical in nature with large drop sizes, hence the greater attenuation. The position of Thaicom at 77°E means a relatively low angle for the dish as we are located at 101ºE. The combination of these factors means that a larger dish size is required to receive, (and transmit) signals in heavy rain conditions.

[The Coder]

I finally got my hands on a picture of their satellite and upon close inspection I think I see the whole problem:

[Farma]

I think the site astral mentioned is here.

Satellite Footprints by Dish Size - Noise Discussion.......

http://www.geo-orbit.org/sizepgs/Noise.html

[astral]

Thanks Farma. That is the one.

[george]

Does that mean that a large IPstar dish (120 cm) is better than the 83cm IPstar dish? or?

[mr_hippo]

Still taking about dishes - I noticed a neighbour had placed a water bottle over his LNB for rain protection and I thought 'What a good idea'. A fellow teacher saw mine and asked if it was for the rain. 'No, placing the bottle there wll fool the satellite into thinking you have a better UBC package - I have the gold package and the bootle gives me the platinum package. He went out and bought a bottle of water and complained when it did not work for him.

[uk_falang]

Walk in to a few satellite shops and say "infosat, agila2ku".

Get all the best UBC channells for free!

The set up including install is less than 5000b.

[JAS21]

Walk in to a few satellite shops and say "infosat, agila2ku".

Get all the best UBC channells for free!

The set up including install is less than 5000b.

Please tell me more..we went into a shop ..mall..and saw Akila Dream..Dynasat 7.5 C/KU whatever that is and and another system..they wanted 20000b for the cheapest. Think company was smart dth

Also dish is 7 feet dia

Offered four choices..Agila KU...Multichoice PAS-7/10...Astro MEASAT-1KU..TELCOM

Sorry but know nothing about Thailand satellite..could wait until early next year if necessary

Edited July 12, 2006 by John45