Specification of Saorsat Setbox or TV Satellite receiving system (More here)

The Saorsat service is proposed to be supplied via Ka-Sat @ 9E, using Ka-Band. The Satellite is many for Internet use and has 80+ spots. One covers Ireland. The satellite was launched sucessfully 21:51 26th Dec 2010  to 07:03 27th Dec 2010.  Reports in October 2011  suggest Public Launch of service in early 2012.

[Update testing received by Apogee on Boards.ie on May 26th 2011 and Gerry Walsh]

Reception will be possible with an HD Satellite receiver (but not a Sky branded Model), but a different kind of LNB and dish to that used for Freesat or Sky is required.

Installing an LNBF for Saorsat

The LNB for Saorsat is aligned to 9E, either on a 80cm dish pointed at 9E or on offset bar on a larger dish pointed at 16E.

The “Offical” LNBF for Saorsat is the Inverto

If your satellite receiver has no settings for Ka-Sat or Ka Band:

1) Select Universal or Ku band LNB

2) Select Eutelsat 9A (if motorised, if Diseqc any satellite NOT 28E)

3) Create a DVB-S2 transponder

  • Frequency 10.765 (really 20.185GHz)
  • Symbol rate 25000
  • Polarisation Vertical (This will select Left hand Circular)
  • FEC 1/2 (or Auto)

If you have a Multiswitch, you only need a single connection to the Low Band and Vertical port. If you have Diseqc and a PVR you need two Diseqec switches. Both connections then used to the same port on both switches.

If you are also using Freesat or Sky on a Multiswitch (Sky as well as other boxes) or Diseqc (Not Sky) system  put the 28.2E LNB on “port 1”

If you are using a “Wavefrontier T90” then you need Horizontal or Right Hand Circular as it reverses the sense of the polarisation. If using a Multiswitch with the “Wavefrontier”  then you need a model designed option of Quad LNB rather than Quattro only and select the “Low + Horizontal” port.

If your receiver does have settings for Ka-Sat:

  • Frequency  20.185GHz
  • Symbol rate 25000
  • Polarisation   Left hand Circular
  • FEC 1/2 (or auto)

Other specifications

Unlike Saorview, RTENL has not yet published a specification or a Test company. However a “Freesat HD” or “Freesat+ HD” should work. If you want Freesat as well as Saorsat you need a Multifeed dish or a 2nd dish and a Multiswitch or Diseqc switch, also a “Freesat HD” receiver or TV that supports Diseqc.

  • DVB-S2 (uses dish). DVB-S will not work
  • HD and regular reception, with SCART (regular TV or downsampled HD) and HDMI for connecting to TVs.
  • MPEG4 H.264 video and AAC audio
  • MHEG5 middleware (Enhanced program guide, text/image pages, menus)
  • Recording is optional
  • Component is optional and should not give HD
  • Probably 80cm dish is the minimum.
  • Dish pointed at Kasat @ 9E, or a Dual /Multifeed dish including 9E as well as possibly 28E (Freesat/Sky). Outside South East a larger dish may be required for multifeed.
  • Ka Band LNBF rather than usual Ku LNBF (Appears to be Left hand Circular on Lygnsat at 20.185GHz). The LNBF has switchable polarity so will work with a T90 Wavefrontier.
  • Unlike common Satellite reception, it will be possible to use a single outlet Ka LNBF to feed any number of setboxes (Common satellite systems need Quad, Octo or Quattro systems)
  • A dual tuner Recording box will only need one coax unlike Sky/Freesat which needs two.
  • A dish installed for Kasat Tooway Internet access can also feed Set-box simply by fitting Satellite signal splitter on cable.
  • A Freesat HD set-box but not a Sky Setbox should work. But only some “Freesat HD” boxes support Dual Feed (Diseqc)
  • Receiving Sky/Freesat and Saorsat will need either a special dual feed 90cm dish or a 2nd 80cm Saorsat dish on existing Sky/Freesat systems.

Using one dish for Multiple Satellite Services.

Triax Multifeed for Freesat/Sky, Astra 19E, Hotbird 13E and Saorsat/Ka-Sat 9E

Use 80cm (pointed at 9E, the 28E offset off arm )  to 110cm (Pointed at 16E) depending on Location. This has been tested with a distribution Multiswitch that can feed 16 satellite tuners (A PVR uses two tuner connections) costing under €250. The existing Ku Band 9E signals are fine and a Sky Digibox is compatible (it only sees the signals from the first LNB, the Freesat & Sky signals). The “LNBF” to receive Sky/Freesat (BBC etc) is on the extreme left. A system like this can feed all the channels from up to four Satellites to over 1000 TVs or Set-boxes in a Guest house, Apartment Block or Hotel. A simple version for home use can feed up to 16 rooms for under €50 a room, including installation, dish and all parts excluding the TV sets or Set-box. Compatible with Sky+ and SkyHD pay systems, but those can’t receive the Saorsat, only the Freesat/Sky channels. So one room can have payTV and all rooms can have TVs with Satellite tuner built in or “Freesat HD” Set-boxes.

Reception outside Ireland.

The reception of Saorsat outside Ireland is likely to be limited. The Ka-Sat uses two polarisations and two bands. These are reused 82 times to give the 82 spots.  Two spots next to each other always differ in Band, Polarity or both. A further away spot can’t be received at all if the same polarity and frequency is used on a nearer spot.

The next graphic a possible assignment, showing area with the same band and polarity as the same colour. Since all the spots/beams are from the same Satellite, it’s impossible to receive Spot Nx  if you move too close to Spot Ny, where N are two matching spots and x and y are two locations.

Saorsat coverage
The Magenta rings are contours of spot signal power.
The coloured spots are official main service areas
Spots of same colour use the same mix of frequency and Polarisation

The first white ring indicate contour of what a published service area might include with a still “normal” size dish (80cm to 110cm)  The outer white ring is low signal needing very large dish (1.2m to 2.5m) as it overlaps same settings of Frenc Calais spot. It must be low enough to cause no interference. The spots come from the SAME satellite, so along a line at tangent (purple line)  to the two lime circles gets equal signal from both feeds (spots) no matter how big the dish is. Because it’s the same satellite. In fact of the four dishes on the satellite, it’s two separate offset feeds on the same dish. You can only separate the signals enough, reliably, by moving within the Irish or French Blue circles (with Lime fill) along the line between their centres. If the symbol rates, power and drop off of signal from France is enough that Co.Down coast to  Ballycastle in Co. Antrim gets only just low enough interference to work on Irish Spot, then the red line marks the edge of possible Irish reception, but only if the French Spot has a similar carrier. As the symbol rate is lowered and frequency shifted, then the Red and Purple lines move toward the French spot.  Conclusion is that if there is no interfering French signal a large dish might work as far as UK Midlands. If there is a French Calais signal overlapping the Saorsat carriers, then no matter what size dish, the coverage is limited to the Welsh coast.

So the  coloured spots on the Ka-Sat maps don’t represent footprints, but service areas. A foot print (signal coverage) has contours of signal strength.

This information is from a longer article on techtir.ie