RTE Announce FTA Saorsat service

Direct TV Ku and Ka are closer, (like 13E Ka and 9E combo I posted). Also Direc TV Ka is circular polarised.

The only single dish option for 9E and 28E is T55 wavefrontier and it's big, ugly, heavy, awkward to align on Kasat and expensive.

I'd go for separate dishes. You can put the 45cm square box above the Sky Dish as it has no arm and 6.5 degree higher elevation if you MUST do one pole. Or if a retro fit, put the square box for kasat some other location.


I'll have a spare square boxed dish, I'll take some photos later of how LNB and bracket works. The earlier photos are obviously not a satellite application (though a real sat dish)

Similar but more expensive model http://www.hm-sat-shop.de/antennen-diverse/megasat-sd-flat-440-flachantenne.html
Select antennen in menu then diverse and scroll down
Megasat / ÖSD Flat 440


The really flat ones on that site are Ku only using built-in LNB and labyrinth mico horns and waveguide combiners so are useless for Ka band (no dish inside)

It's not offset, so it really would be at 29 degree elevation like that, approx. No need to dis-assemble case, the LNB is held by a plastic bracket and lock screw at rear.

If you order direct from Turkish factory you can get without the normally included Ku LNB. They can probably source suitable Ka LNB. Some LNB are too short for horn to be at focus.

WARNING Will Robinson!
These 44cm dish in a plastic box are no good in Ireland for Sky when it rains. Maybe OK in Wexford. Definitely OK in South East of England. But should be fine for Kasat if we can find the correct LNB. No need to worry and test till hopefully successful Kasat commissioning a few weeks or month after launch (hopefully OK too)

Sponge Bob wrote: »

Is Ka Sat supposed to deliver a higher power spot beam over Ireland Watty , out of interest. Your dish looks scarily small by our normal standards.

I take your point on smaller satellite shadow areas (ie north side of mountains in the west) because of better elevation in the sky.

Currently the only dedicated spot for Ireland is this

It's old, doesn't do that amount of power. Used by BBC and Five for feeds to TX sites, by RTE and BBC for OB and by Schools here for Satellite Internet/"Broadband" (VSAT). It also has no space left.
http://www.lyngsat.com/intel907.html

Sky/Freesat is a constellation. It only needs a 43cm /45cm dish (one of those small boxes) in London. It's Astra 2A, 2B, 2D and Eurobird 1

Astra2A and 2B South Beam


Astra2A and 2B North Beam


Astra2D North Beam


Eurobird1 S1


Eurobird1 Fixed

These footprints don't take account that the rain fade is worse at lower elevations (the further West and North the worse). Elevation is about 22.5 in middle of Ireland.

The recommended Sky dish in SE England is 45cm and in Ireland is 65cm. But taking account of rain fade, transponder power dropping with age, you can see that in Dublin a 50cm might be fine and in Donegal and Kerry 80cm might be needed for same performance. 65cm is a compromise. Those in West, North West and South West actually get more pixellation and breakup than those in Dublin. It happens more often to as the West as nearly 6 times the rainfall.


Kasat proposed Spots

I have shown a few spots here of the EIGHTY the satellite has. It's probably going to be the biggest and most powerful satellite ever launched in europe.

For the same TX power (and newer satellites tend to be more powerful) a smaller spot is more concentrated so have more effective power.
Ka is nearly twice the frequency of Ku (Astra 2x / Eurobird 1) so a dish has nearly x4 gain. This means a 43cm dish on ka is close to same signal as 75cm to 80cm on Sky/Freesat.

But we actually have a dedicated spot


The spots that are the same colours are the same channels reused. Unlike Ku (Sky) where the constellation gives you the whole band, each Ka Spot is about 1/4 of the channels only. This also means that it's likely that distribution to multiple receivers can use a single output LNB and simply split the signal like TV (If done properly, even if all the possible transponders used, all should be same H/V and Tone On/Off). If they are using greater than 2GHz, it's possible to have a couple of different Ka LNBs for different spot groups.

It's probable in a clear sky that a 20cm to 30cm dish might work! The large (for ka Band!) size is to ensure rain fade margin.

In South East UK and in many parts of Europe Mainland the tiny lidl Camper dish works fine in rain if you are in the "hot" part of all the beams/spots you need. Up till now we have been on the edge of coverage for almost all Irish/UK services. This time we get our own spot, Unlike Sky/Freesat where the signal in West of Ireland is rubbish compared to South East England.

Ka generally uses a much smaller dish than Ku.

Also the Tooway is VSAT using DOCSIS. It has a transmitter, so for a working two way link (for Internet) VSAT always needs a larger dish than TVRO/DTH (Ordinary TV reception only). The Tooway people assured me that VSAT on Kasat only needs a 45cm dish.

The other issues are Modulation type, Transponder width, FEC and Symbol rate. These also affect dish size. DVB-s2 is more efficient than DVB-s. On Ku and VSAT that is used to get more data. On Ka the TV will likely use the modulation to ensure rain margin. The VSAT transponders are adaptive. They actually change modulation on Kasat to stop loss of signal during heavy rain and turn up the speed to near double older Ku VSAT in clear skies. Obviously TV transponder is fixed symbol rate.

I really think the "one dish" rule is not going to be an issue as the kasat dish can be in a box and will be so small and unobtrusive. They have never applied it to MMDS dishes which are bigger and uglier.

Anyhow, obviously we can test before madly installing loads of dishes. Spectrum Analyser with decoder for DVBs2 to also measure BER etc.

For Border counties the N.I./Scotland spot is easy.
For Waterford to Dundalk, the Welsh/Cornish spot is easier.
For rest of Ireland the dish size would rise rapidly. A larger dish needs to be very rigid and is very tricky to align on Ka without a spectrum Analyser.


But Freesat has a large installed base. They won't consider it as the changing of all the LNBs is too expensive. The four UK spots will be mostly rural Internet, esp. now that the Con-LibDems have shelved the Rural universal 2Mbps Broadband.

Tooway on kasat is likely to offer same or higher cap, more consistent 3Mbps or more than Mobile and possibly less than €20 month. But 790ms minimum ping. Installers will need good test gear.

Yes there are, they are no different in that regard. You cannot split a satellite signal or use a distribution amp no matter what band it is.

jobyrne30 wrote: »

This might be a stupid question but I'm sure it's of interest to many people. Is there such a thing a quad or octo Ka band LNB's ? Or can the signal be split multiple ways via a distribution amp similar to that use for aerials ?

True if they use only the one mux or two mux in the same polarity/band then in theory you could split but then we get into cable/amp losses so I think its going to be cheaper to go the lnb route or perhaps unicable . What happens though if another service starts that you want in the future on another polarity or band, you end up having to re cable.

Interesting times ahead Watty

watty wrote: »

So it's unlikely that Quad, Quattro or Octo ever needed.[/B] It's likely on Kasat that for any one spot all channels are same polarity and part of band

I'm 99.9% sure each spot is only one part of band.
I'm 100% sure each spot is only one polarity.

Infact for the single dish Satellite Internet + TV to work, the ALL the downlink in the spot has to be same part of band and same polarity as they simply T the RX coax to Modem and setbox. The TX uses a separate higher band and opposite polarity.

Hotbird 6 13E ka layout


You can see clearly on this the diplex filter guard band for frequency re-use per spot. (on downlink and uplink)
(WARNING: This may not be the frequency plan for KaSat!) The Hotbird Ka @ 13E has only 4 spots. The Kasat has a staggering 80 spots. but only FOUR different sets of "frequency reuse". Thus kasat is a x10 version of the existing 13E Ka Tooway system.

The TX /RX separation is via clever mechanical diplex filter and polarisation splitter called an Orthomode Transducer
http://en.wikipedia.org/wiki/Orthomode_transducer

So it's about 99.999% likely that kasat and future Ka band we can use passive splitters, single output LNBs and only need an amp for maybe 8 or 16 way split. Unlike a TV aerial, there is a Cable driving high level IF amp in the LNB. The modern LNBs have a massive output level. The dish really sets the SNR. The splitter will attenuate noise too.

I'd imagine only Guest houses, Hotels, Apartments will need the 950MHz to 2GHz sat amps. You can get splitters that will do 5MHz to 2GHz, but I'd stick to 900MHz to 2500MHz splitters, better performance.

How does €12M p.a. to more likely €21M p.a. cost less than €1.5M p.a.? It's COST driven, not tech driven.

It's not RTE's tech. they are renting this as it's at least 1/10th the cost of ANY possible other solution.

Also the capacity to have all the Irish services and simulcast in HD on Satellite doesn't even exist at 28.2.

This solution needs no SD / HD simulcast. Like Saorview, RTE can switch to HD on demand initially for special features and then HD only when full HD content is available. On installed Skybox base that's impossible.

We could be looking at 25,000+ households with no free Irish digital services without this, maybe 20,000 needing BIG aerials. RTE are in serious trouble if the launch fails as really the plan B doesn't exist. No money for more relays, which even at UK level of coverage we would have 10,000+ with no or poor DTT.

For SD the Saorview on 28.2E is €12M p.a. to more likely €21M p.a. For HD, it's €40M to €80M a year instead of €4M on Kasat, but the capacity for 9 new HD on 28.2 doesn't exist.

jobyrne30 wrote: »

Cheers Tony and Watty for answering my earlier question.

Your welcome. Once again thanks for your posts on other threads, you seem to be very well informed.

rlogue wrote: »

One thing that makes me very negative is the complete lack of regard by RTE for the diaspora audience.

I agree, but that's a completely separate issue. It should be funded by Dept of Foreign affairs, like almost every other country. Apart from a few half hearted SW Radio and RTE Radio on Satellite, we are one of the worst in the world in the nearly 90 years of Irish Broadcasting.

rlogue wrote: »

Where are RTE going to find the 1.5 million to fund the Saorsat service when they said they didn't have the 1 million or so to fund the RTE International service?

Of course Eamon Ryan let them get away with it.

It would cost more that that to run the last 7% to 5% of Terrestrial relays. The Roll out cost for the last 5% probably €15m.
RTE International service is a Government idea and the Government should pay for it directly. This solution saves RTE money and ensures an identical copy of Saorview TV & Radio to people that would not get DTT no matter how much was spent.

This is 9 channels now, more later and 12 Radio channels. And backup feed for ALL RTE DTT & DAB feeds.
Look here http://www.lyngsat.com/intel907.html
scroll to bottom of page.
Even BBC and Five don't use Sky for backup.
I looked at this satellite for Internet and TV for Ireland. A real genuine commercial project. Not enough capacity left.
Also while it's the only cheapish non 28.2E with Irish Spot it covers all of UK also. No use for Saorview without expensive card scheme.

Even the cheapest Real Digital TV non-Murdoch card scheme would cost more than €1.5M a year. I feel your pain about the ex-pat situation, but there isn't a "one fits all" scheme for Domestic TV and outside Ireland unless you are big country or don't speak English.

This is not a competitor to Sky & UPC. It's for people that don't want Sky or UPC and can't get DTT. Because the dish is tiny compared to a Sky/Freesat dish in Ireland (Zone 2) and can even be in a plastic box, people can easily have Freesat also. Possibly Freesat & Saorsat on one receiver. Unlike Sky it's almost certain one small dish (that is less obtrusive than MMDS and need not look like a dish) can feed any number of sets without multiple cables from dish or complex traditional Sat IF distribution gear.

Onthe3rdDay wrote: »

Actually The BBC have used SKY for backup in the past in the channel Islands.

They probably still use it for some things, or Crowncastle or who ever minds the TX sites since the Government forced the sale of them.

watty wrote: »

This is not a competitor to Sky & UPC. It's for people that don't want Sky or UPC and can't get DTT. Because the dish is tiny compared to a Sky/Freesat dish in Ireland (Zone 2) and can even be in a plastic box, people can easily have Freesat also. Possibly Freesat & Saorsat on one receiver. Unlike Sky it's almost certain one small dish (that is less obtrusive than MMDS and need not look like a dish) can feed any number of sets without multiple cables from dish or complex traditional Sat IF distribution gear.

I think it is a good idea. The whole thing still sounds a little clumsy - because they are only looking at this from the RTE point of view, and really it should be consumer driven.

I think what we need to know now, is:

* What analogue transmitters will be decomissioned by RTE
* What new digital transmitters will be commissioned
* How many viewers will rely on the new satellite service

I still think it is outrageous that in some areas people will have to shell out 250euro for a sat installation, whereas others will just have to plug in a box for DTT. Yes, there is a cost associated - but by the time this gets going people will be able to source cheaper STBs for DTT.

mike65 wrote: »

There a lot of guess work, the cohort that actually requires a Sat to get a decent picture is already small and the numbers who will need this new service is therefore smaller again cos some will already have SKY as mentioned. Now some of the Irish via SKY audience are doing so only for RTE/TV3/TG4 and will drop SKY but others will see no need as they rather like enough of the other stuff to pay for it.

For RTE Saorasts real value would appear to be as a back-up facility.

The UK has freesat to support a notional 1% after analogue switch off.

The real value is for 2% to 7% of real people who would have no Irish TV. There is a universal obligation. Sky will not have all the Irish channels. The "back-up" feature is icing on the cake.

5% is 25,000 people! They have a right to have exactly the same service as people in Dundrum from Three Rock. ALL the channels, what ever HD there is. All the DAB channels will be on DTT & Sat also.

That works out at €60 a person per year.
If you did UK level of coverage then the extra rollout cost could be €20M and over €1.5M running cost. You STILL need Sat for last 1%. = €300 a year!

Because there is no card / encryption costs if 10% of people need it the cost is only €30 a year.

Basically I will be upset if those in areas that will never have DTT, don't get free install as this solution doesn't cost RTE €1.5M a year. It saves more than that a year.