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RTE Announce FTA Saorsat service
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Frankly, there's more chance of my cat spontaneously combusting than the LNBF being overloaded.
I agree it seems unlikely on the face of it. The equivalent today might be a 2.4m dish pointed at 28.2E in middle of Ireland
1m vs 30cm is almost x10 power.
All of Ireland is in the "Hot" part of spot beam.
You won't break it. But I'll only be sure its an "OK" idea when I have tested a Ka LNBF on the new satellite (hopefully next year) with my 110cm dish.
Also it's not just QPSK. Potentially 8PSK signals so you need a bit more linearity. Also an Ka LNB may not have the same dynamic range as a Ku LNB. We don't know what the sensible limits are.
(If you use a Mirror only 15cm you can set the cat on fire
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I agree it seems unlikely on the face of it. The equivalent today might be a 2.4m dish pointed at 28.2E in middle of Ireland
A 2.4M pointed at 28.2E doesn't really come near to overloading a Ku-LNBF though.(If you use a Mirror only 15cm you can set the cat on fire )
You should try posting that over on the 'Pets' forum!!!
Eagle Aspen also manufacture Ka-LNBs and as a brand are usually cheap.
http://www.eagleaspen.com/products/products_1.php?id=20
No prices that I can find though.
As it happens they also manufacture LNBFs for DirecTV, including this model which, from reading some of the specs, does both Ku and Ka (lo and hi) across 3 sats, with 4 outputs for <$50.
http://cgi.ebay.com/New-Slimline-3-KA-KU-Directv-lnb-DTV-SL3-HD-KAKU-SL3PIG-/330457701698?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item4cf0d05d42
[edit] For the price, one of them would be interesting to mess about with. But difficult to figure out how LNB and band switching is implemented on them.0 -
Forget ANYTHING for DirecTV as they use circular polarisation. Their stuff is useless on any other system It's very non-standard.
The eagleaspen Ka LNB is for a VSAT. The price would not be relevant to a TVRO LNBF
Ka Band: Max Input Power Operating -70 dBm
Interestingly they don't list a "Max Input Power Operating" on the ku LNBs for VSAT that they sell.
Please note that it was a cat related to Schrödinger's. No actual pets were harmed.0 -
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Forget ANYTHING for DirecTV as they use circular polarisation. Their stuff is useless on any other system It's very non-standard.
Doesn't matter if the H/V TPs are not the same freqs - even if they are, taking a pliers to the feedhorn will sort it.Interestingly they don't list a "Max Input Power Operating" on the ku LNBs for VSAT that they sell.
Probably coz like most Ku-LNB/F manufacturers, they can't be bothered.
A bit more reading on the DirecTV LNBFs, and there is no bandswitching on Ka. It's a single LO at 18.050GHz which drops the Ka-Hi and Ka-Lo to the L- and B-bands. Switching between the different positions is done by 22KHz on/off.
Zintec also make Ka-LNBS:
http://www.zintech.com.tw/modules/product/page.php?tbdsn=85
And then there is this piece of (expensive!) kit which covers all the way from 17.7-21.2GHz using 4x LOs.
http://www.acorde.ru/datasheets/Ka-Band/ACLNB/ACLNB-Ka-17.7-21.2.pdf0 -
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NiceBesides acorde ACLNB-Ka Standard ....
the KA LNB S3 (19.7-20.2 GHz for the downlink) http://www.elsov.ru/products/texts/lnb-kae.pdf
(by the way Malwarebytes is going bananas because of where one of those photos above is being hosted)
For people interested in Tech stuff, info not needed for ordinary user of Saorsat.
For the un-initiated that don't know what we are talking about, VSAT= Very Small Aperture Terminal.Very Small is less than 2.4m!
Aperture means reflector, dish or horn of some kind
Terminal means a two-way modem. Receiver and Transmitter. Not just used for Internet. The "plumbing" in the picture thus has two coax cables, a TX IF and RX IF.
Some Explanations
Not directly related to Saorsat, but Saorsat will use a Satellite primarily intended for VSAT. (Internet by Satellite)
part of VSAT for Ku
The feed or horn bolts on the left for signal focused by dish.
The first part is an OMT. Orthmode Transducer. It separates Horizontal and Vertical polarised signals. The Receiver and Transmitter always are on opposite polarity, thus Circular is rarely used for VSAT as it's more awkward to have both on one feed. The next part on top is a Mechanical filter to allow the Receive band and block the higher Transmit band.
The small box on top is LNB that only has one fixed orthogonal polarity. The large finned box on bottom is Transmit (TX) IF up converter and a Power Amplifier (0.5W to 20W depending on system), the one shown is 2W or 4W.
To swap from TX on H and RX on V to the other polarity of TX on V and RX on H, the whole assembly is bolted on the feed at right angles. The inlet waveguide and feed horn are circular shape to work equally with both polarities. The H and V ports on the OMT are rectangular waveguides at 90 degree orientation usually. The BUC and LNB are always rectangular.
A domestic LNBF for Orthogonal (H & V) is always circular wave guide with two studs/pins to pick up H & V signals. The H or V is then selected electronically by > 17V = H and < 14V = V (typically V is 12V to 13V and H is 18V to 20V)0 -
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Nobody claimed it was for normal use. I said it was cheap and to "mess about with".
Another blanket statement. Not on C-band. When a Ka-LNBF comes along, I'll post a link to that too. In the meantime, I'd rather you didn't "interpolate" every post I make.
So that's why you started going on about OMTs?
Who advised anyone to go out and buy a Ka-LNB?
C-band is not really meant for DTH. It's primarily Head ends. It needs a big dish with a matched feed. Hence LNBF is rare. Volume Domestic solutions are all LNBF.
Calm down
Your links / post are fine. I'm just clarifying it's not stuff for casual user to "mess about with", nor for a real DTH Ka solution. I mentioned the VSAT stuff and OMTs etc because unusually for us the SAME satellite and receive polarity will do for Saorsat and two way Internet.
Also I mentioned it to try an clarify why the DirecTV (no VSAT on it and Circular) and Kasat are different (Primarily VSAT and orthogonal).
I think we have been a bit at cross purposes. Sorry if any offence given.
If you or anyone else want to use a bare Ka LNB I can post a design of easy to make horn feed with correct aperture for a regular dish, made by cutting and soldering 5 pieces of plain copper PCB out of Maplin. (Brass or copper sheet expensive and folding a single piece aluminium needs skill and tools).
I'm all in favour of folks doing tech stuff for fun.0 -
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Launch date for Ka-Sat satellite is November 25 according to the French article
http://www.lepoint.fr/high-tech-internet/ka-sat-pour-les-exclus-du-numerique-05-08-2010-1222124_47.php[/QUOTE
French to English translation
The tests are completed. Still some loose ends, like putting the antennas and Ka-Sat will be ready to be shipped on the Baikonur cosmodrome (Kazakhstan), where it should be launched for Eutelsat, November 25 next. Manufactured by Astrium, a subsidiary of EADS, is dedicated to services and space hardware, this new generation of satellites designed to provide broadband to all those excluded from the digital airwaves are struggling to achieve and which will never be connected to ADSL. 30 million homes in Europe. To date, the general public, offering two-way satellite based on two main broadband services: the Tooway provided by the satellite Hot Bird 6 and Eutelsat Eurobird 3, and that of ASTRA2Connect operator SES -Astra, which manages the satellite system of the same name. These two services (and Tooway ASTRA2Connect) are marketed by distributors (Numeo, Sat2Way, NordNet, Vivéole) as a package, or not associated with offers IP telephony and television. The connection kits are shipped to the customer who enjoys a hotline for the installation. With K-SAT, Eutelsat going into high gear. With its 80 Ka-band beams, the new satellite will allow higher speeds for a cost eight times less expensive. The same frequency can in fact be reused twenty times, thus lowering significantly the cost of the spectrum. Eutelsat, which is about 200,000 subscribers in France, ahead respectively 10 Mbps downstream and 1024 kbps in, against 3.6 Mbps and 384 kbps now. The new service should be marketed in the first quarter of 2011. To qualify, subscribers must change current antenna.
Noreen0 -
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The Proton rocket that is taking the Ka-Sat satellite has had 8 failures out of 115 launches from 1996 to present. http://en.wikipedia.org/wiki/Proton_(rocket)
That's a 93% success rate. (Not all launches listed, but they say it's 96% success rate overall)
Maybe that's why RTENL are very slow in releasing information. They don't have a plan b, if it fails.Are we going to blame RTENL if the rocket fails? Jesus, these guys really get a tough time on here.
too right slegs... I'd be delighted if everything I did had a 93%-96% success rate
:D:D 0 -
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