Upgrading Ubc To Bigger Dish To Help Avoid Rain Fade

[bluechipit]

Guys,

Quick question. If I grabbed a 6 foot C-Band dish and installed this LNB:

http://9sats.com/product/product.detail.php?&cat=54&id=1308

Would this set up then work OK with Truevisions after the dish has been aligned properly?

Cheers in advance,

Matt.

[ThaidDown]

I'd be more concerned with the dish. Ku band wavelengths are only up to an inch .(if I remember right) So a solid dish would be preferred. A mesh dish would need 'holes' much less than 1/4 wavelength to avoid signal loss. Of course not a problem for C band as wavelengths 3-6 inches.You would also need to know the exact focal length of the dish to mount the LNB.

Otherwise do not see why should not work fine. Ready to be corrected by the experts though.

[JakeBKK]

I'd be more concerned with the dish. Ku band wavelengths are only up to an inch .(if I remember right) So a solid dish would be preferred. A mesh dish would need 'holes' much less than 1/4 wavelength to avoid signal loss. Of course not a problem for C band as wavelengths 3-6 inches.You would also need to know the exact focal length of the dish to mount the LNB.

Otherwise do not see why should not work fine. Ready to be corrected by the experts though.

Full wave Ku band is between 1.67-1.11 cm so if the mash had holes bigger than ~ 0,56 cm in theory this could be an issue generating interferences. Piratically a mesh behaves like a sold one , except less weight and wind load.

Edited July 21, 2012 by JakeBKK

[IPTVThailand]

Before you consider to change your dish you may want to try this option as i also have installed on my ubc dish its 95% better performance in the rain and i only loose the signal if heavy heavy rain http://www.satellitetvthailand.net/product_info.php?cPath=28_36_41&products_id=85

These lnb are designed for europe and made in europe where it rains everyday !!

and not made in thailand .

iT Really does improve the signal and rain loss

[bluechipit]

I actually have this LNB installed on my current dish:

http://www.satellitetvthailand.net/product_info.php?products_id=86

However, after reading a few posts on the satellite forums it made sense that investing in a larger dish was a better option that the LNB upgrade. Is it possible to buy larger solid Ku dish in Thailand?

[bluechipit]

Sorry, should have had a search before posting. I might go for one of these and couple if with my Megasat LNB

http://9sats.com/product/product.detail.php?&id=156

[JakeBKK]

Mesh will do fine. Is better do have a stronger singal ( larger dish more gain) , so if you double the sizse you gain 6dB more this is an advantage over signal amplification e.g. high gain lnb or cable amp..

Edited July 21, 2012 by JakeBKK

[monty]

Would work very well.

Although the lnb is overkill, no need for dual c-band/dual ku-band.

Plain Ku will do just fine if matched to your dish (i.e. the lnb's used on the small off-set dishes will not work without special custom mounting stuff).

Also, the True receivers are set for lnb's with a l.o. Frequency of 11300, so make sure you get that one correct.

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[IPTVThailand]

I actually have this LNB installed on my current dish:

http://www.satellite...?products_id=86

However, after reading a few posts on the satellite forums it made sense that investing in a larger dish was a better option that the LNB upgrade. Is it possible to buy larger solid Ku dish in Thailand?

yes at moment can get 90cm or 120 cm http://www.9sats.com/product/product.detail.php?&cat=50.52&id=156

follow the link they have in stock

[Pib]

Yes, it will help greatly. I'm now on cable TrueVisions, but before I was on satellite TrueVisions here in Bangkok. Rainfade was problem with the True-provided 75cm dish and I had a clear shot and accurately aligned dish--I did the alignment myself to ensure max signal strength/quality...my alignment gained about 3db over the True tech alignment done during original installation. I also have a C band system using a 1.7M (5.5ft) dish. What I did was bought a combo/integrated C/KU band LNB and replaced the standard C band LNB on the C band dish. I bought the combo LNB in order to mount the C and KU bank LNB directly in the middle/prime focus area of the dish. This link takes you to the type I bought. Link. The KU band LNB is the single output on very end and the two C band outputs in the middle area.

The great majority of my rainfade was gone...I would still experience a very short rainfade in a bad thunderstorm...but I would have to say 90% of my rainfade went away due to the increased gain (approx 4-6 db) provided by the large C band dish. I also have another KU band LNB mounted on the same fixed C-band dish for pickup of NSS6 satellite signals, but it is an offset mount (not mounted directly in the center of the dish since the dish already has the combo LNB there). I still use this C/KU band setup along with my cable TrueVisions....the wife like a lot of Thai channels on C band that TrueVisions don't carry.

A person could just move the True KU band LNB from the True 75cm dish and offset mount it on a C band dish like I did with the NSS6 KU band LNB, but you would lose the signal gain advantage of using a larger dish because the LNB is not placed in the dead center/max gain area of the dish. You would end up with approx the same gain as you had on the small True dish.

Regarding the 2 output KU band combo/integrated LNB in the OP's link, since TrueVisions only uses the Horizontal (H) polarity a person don't really need a two output LNB to run say 2 receivers...just run the signal to a two way splitter and let it feed two boxes....that's the way True visions does it to feed two boxes from their one output LNB. That's why I bought/installed the one output KU band (11300Mhz) combo LNB and feed it to a splitter--and let's just say it was one of those "alternate" type splitters that feed up to six boxes versus a simple two-way 3 db splitter...'nough said.

Edited July 21, 2012 by Pib

[bluechipit]

Pib,

Thanks for the advice. I was going to go with the 2 port LNB to feed both of my boxes, but will go with the set up you described, one port lnb to a splitter box.

Can't wait to get this setup, rain-fade sucks, especially during the last 10 minutes of a football game when both teams are drawing and there could be a winning goal at any time... : )

Cheers,

Matt.

[bobl]

Save your money. Here you go...

[Pib]

Will never work in Thailand because the umbrella is the wrong color...gotta be red, yellow, or pink.

[IPTVThailand]

It will be intresting to see what happens in the rain with the New HD Channels as hd needs far more signal quality and strengh .

One good reason for Iptv at least when its heavy you can still watch tv .

[longball53098]

It will be intresting to see what happens in the rain with the New HD Channels as hd needs far more signal quality and strengh .

One good reason for Iptv at least when its heavy you can still watch tv .

IPTV will work if the internet connection is adequate. As you have already stated you need a constant 5mb line for the HD channels to work properly. There are many of us here that can barely get a decent 3mb even paying for a higher speed line

[Pib]

It will be intresting to see what happens in the rain with the New HD Channels as hd needs far more signal quality and strengh .

What makes you say this about a digital transmission, which is not so much relying on signal strength but just getting enough signal to decode the pulsed transmission....pretty much you either have a signal or you don't....that is, a low level signal will give you just as good a picture as a high level signal. But I will admit just before you totally lose a digital TV transmission you can start seeing some pixelization (loss pixels/distored transmission)...it's that signal strength boundary area where you have enough signal, then you don't, then you do, etc.

[monty]

It will be intresting to see what happens in the rain with the New HD Channels as hd needs far more signal quality and strengh .

One good reason for Iptv at least when its heavy you can still watch tv .

Not correct. SatTV is digital, it works or it doesn't.

There is a small grey area where you do get a lock on a transponder, but where there are errors in the received data.

On most receivers you can check the ber (bit error rate) which should be 0. When it goes up, you'll likely get pixelation and sqeaky sound effects...

The onlu difference when transmitting HD is that you can cram less channels on a transponder at a certain SR/fec, partly offset by using higher/better compression, hence the move to mpeg4...

You don't need more signal but more cpu power in the receiver as decoding mpeg4 is more cpu intensive then mpeg2...

Far as i know True is using transponders with a SR of 30000 and fec at 2/3 (8 of them) and has been for a long time now...

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[JakeBKK]

It will be intresting to see what happens in the rain with the New HD Channels as hd needs far more signal quality and strengh .

One good reason for Iptv at least when its heavy you can still watch tv .

[JakeBKK]

It will be intresting to see what happens in the rain with the New HD Channels as hd needs far more signal quality and strengh .

One good reason for Iptv at least when its heavy you can still watch tv .

Not correct. SatTV is digital, it works or it doesn't.

There is a small grey area where you do get a lock on a transponder, but where there are errors in the received data.

On most receivers you can check the ber (bit error rate) which should be 0. When it goes up, you'll likely get pixelation and sqeaky sound effects...

The onlu difference when transmitting HD is that you can cram less channels on a transponder at a certain SR/fec, partly offset by using higher/better compression, hence the move to mpeg4...

You don't need more signal but more cpu power in the receiver as decoding mpeg4 is more cpu intensive then mpeg2...

Far as i know True is using transponders with a SR of 30000 and fec at 2/3 (8 of them) and has been for a long time now...

Sent from my GT-I9001 using Thaivisa Connect App

I'll guess they shaped the bitrate a bit to get this all working on their bandwith package on thaicom 5

[monty]

It will be intresting to see what happens in the rain with the New HD Channels as hd needs far more signal quality and strengh .

One good reason for Iptv at least when its heavy you can still watch tv .

Not correct. SatTV is digital, it works or it doesn't.

There is a small grey area where you do get a lock on a transponder, but where there are errors in the received data.

On most receivers you can check the ber (bit error rate) which should be 0. When it goes up, you'll likely get pixelation and sqeaky sound effects...

The onlu difference when transmitting HD is that you can cram less channels on a transponder at a certain SR/fec, partly offset by using higher/better compression, hence the move to mpeg4...

You don't need more signal but more cpu power in the receiver as decoding mpeg4 is more cpu intensive then mpeg2...

Far as i know True is using transponders with a SR of 30000 and fec at 2/3 (8 of them) and has been for a long time now...

Sent from my GT-I9001 using Thaivisa Connect App

I'll guess they shaped the bitrate a bit to get this all working on their bandwith package on thaicom 5

Guess that is why they moved the bulk of their programming onto mpeg4.

Their 8 transponders supported around 200 SD channels and I think 5HD channels using mpeg2.

Conservative guess by moving to mpeg 4 and keeping the same quality (or lack of) should gain them at least 50% in channel capacaty, plenty to add all their HD channels...

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[Pib]

Yeap, with the different compression algorithms used by MPEG2 and MPEG4, MPEG4 requires about half the bandwidth of MPEG2.

[TS79]

I actually have this LNB installed on my current dish:

http://www.satellite...?products_id=86

However, after reading a few posts on the satellite forums it made sense that investing in a larger dish was a better option that the LNB upgrade. Is it possible to buy larger solid Ku dish in Thailand?

yes at moment can get 90cm or 120 cm http://www.9sats.com...at=50.52&id=156

follow the link they have in stock

Hi, just trying to understand something...I too have issues with rain-fade on my standard True Vision dish and would like to get a larger dish to reduce the rain-fade.

The link you post to the 90 / 120cm diameter dish, i see this is an offset dish so am I right to assume that all of the signal received by the dish will not be focussed onto the LNB and thus not maximumising the potential of the increased size of dish? Or is the difference in signal received minimal between the offset dish and a dish where the LNB is mounted in the centre?

The standard True dish is 75cm, I dunno of this logic is correct but if I were to assume the dish was flat then it would have an area of 0.44m2, a 120cm dish would have an area of 1.13m2 so effectively more than double the surface area to receive a signal? Then an offset 120cm dish would still be receiving a lot more signal strength?

Go easy on me, I'm just trying to understand the differences of offset / centre and larger dishes to how signal strength is effected.

T.

[monty]

An offset dish does reflect all received signal onto the lnb, only it looks out to the sky at an angle, bit like you would stand in front of a mirror at an angle.

So the dish actually looks higher up in the sky then what the angle of the dish would indicate.

With as advantage that you can receive a satellite virtually straight up without the solid dish collecting water!

Then on the size, for example the jonsa 75 cm dish has a gain of 38.4 dBi, the 90 cm has a gain of 39.82 dBi and the 120 cm dish has 42.4 dBi gain.

Considering every 3dBi extra gain represents a doubling of the signal, the extra 4 dBi on the 120 cm dish is quite a big improvement on signal strength over the 75 cm!

While the gain numbers dish manufacturers supply often have to be taken with a grain of salt, you are indeed right that a relatively small increase in diameter results in a much bigger increase in signal received...

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[jsat]

We have a 3.2m (10') petal solid dish here - first offer over THB 10,000, (normal cost at trade THB 32,000 but this is used) take it away in your pick up truck.

[monty]

We have a 3.2m (10') petal solid dish here - first offer over THB 10,000, (normal cost at trade THB 32,000 but this is used) take it away in your pick up truck.

Bit of a wind catcher is it?

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[wayned]

If you double the size of the dish you will get approximate 6db increase in gain. Although theoretically you might see some improvement in light rain, it will never eliminate "rain fade". Heavy rain can attenuate the signal more than 40db. I have noticed that the new "HD" box seems to be more sensitive to rain but since the old one no longer works, I can't compare them side by side. I mentioned this to True and they said that they are continually updating there software via direct upload to "enhance the stability of the signal with the new HD box". This is their words exactly via e-mail. The latest software version is 401 which was uploaded to my box on 23 August. Don't really see any improvement, when ithe signal goes out I know it's time to get the laundry in. True would probably try to charge more if they knew that I was using it as a rain detector!

[jbrain]

We have a 3.2m (10') petal solid dish here - first offer over THB 10,000, (normal cost at trade THB 32,000 but this is used) take it away in your pick up truck.

Why would a 3.2 meter solid dish be almost 5 times the price of a 1.80 meter solid offset dish.

D19 หน้า จาน KU180cm

( 7,000.-)

หน้าจาน 180 cm

ใช้งานระบบ โดยเฉพาะรับ Dream TV

Edited September 16, 2012 by jbrain

[kingbilly]

In my experience of Thai Dish Installations - you would be better off getting someone who was competent in aligning and peaking your current dish with a decent signal meter rather than having Somchai 1 watching the TV while Somchai 2 moves it left a bit right a bit up a bit down a bit - Bernie the Bolt!

Rain fade should not be an issue not with those dishes, as said earlier in the days of analogue it was an issue which could be overcome with various folded wet towels and a TV close by - these days in the digital age it should either work or turn to static "Blocks" then blue screen - I have seen more than 10 installations here usually "True" (the little red dish) and not one of them even used a meter for signal strength. The other thing that might be worth a try is to run your reciver for half an hour to warm up the LNB (They might be powered on all the time these days) then adjust the Local Oscillator frequency ever so slightly in your receiver set up menu - They are normally 9.750 GHz and 10.600GHz. in a standard Universal LNB, however, manufacturing tolerances are generally +/- 3.0Mhz but less scrupulous brands will be +/-5MHz or more and set up at whatever ambient temperature who knows!

In temperatures here which are quite high, the LO will tend to drift a little low in high temperatures, and then increase in frequency as it cools off.

Edited September 18, 2012 by kingbilly

[kingbilly]

If you double the size of the dish you will get approximate 6db increase in gain. Although theoretically you might see some improvement in light rain, it will never eliminate "rain fade". Heavy rain can attenuate the signal more than 40db. I have noticed that the new "HD" box seems to be more sensitive to rain but since the old one no longer works, I can't compare them side by side. I mentioned this to True and they said that they are continually updating there software via direct upload to "enhance the stability of the signal with the new HD box". This is their words exactly via e-mail. The latest software version is 401 which was uploaded to my box on 23 August. Don't really see any improvement, when ithe signal goes out I know it's time to get the laundry in. True would probably try to charge more if they knew that I was using it as a rain detector!

Many years ago, when I was involved in the manufacture of LNB's for Sky etc. we had a test laughingly known as the "PEA" Test - no, it did not involve Golden Showers, it involved someone climbing onto the roof of the lab with a 2KG bag of Birds Eye frozen peas, they were rained down onto the LNB to simulate hailstones! (They actually proved quite interesting as to how the LNB would perform under vibration) Back then, the LNB was state of the art electronics and commanded a high price - I think the old Blue Caps were over 40 quid to Sky at the time - 2.4dB noise figure and 46dB gain - now everywhere is flooded with cheap Chinese <deleted>! that costs about 2 dollars in materials.

[TS79]

In my experience of Thai Dish Installations - you would be better off getting someone who was competent in aligning and peaking your current dish with a decent signal meter rather than having Somchai 1 watching the TV while Somchai 2 moves it left a bit right a bit up a bit down a bit - Bernie the Bolt!

It is bizarre that a company as big as TRUE do not have their installation contractors using signal strength meters. It would probably reduce the amount of pi$$ed off customer calls to their call centre if they did and would probably save installation time between Somchai 1 and 2 shouting back and forth.

On a side note, is it worth installing an inline amplifier in the cable between LNB and decoder to boost up the signal?