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138 139TELE-audiovision International — The World‘s Largest Digital TV Trade Magazine — 07-08/2013 — www.TELE-audiovision.com www.TELE-audiovision.com — 07-08/2013 — TELE-audiovision International — 全球发行量最大的数字电视杂志

New in the Ka-Band - Update

• a new band for the satellite enthusiast• hard to receive as no consumer LNBs are available• possible to receive programmes directly from African countries• Ka-band reception suitable for DYI DXers

Satellite Reception in the Ka-Band

View of Vitor's workshop. Using the meters available to him, he can detect virtually all satellite signals. Currently he focuses on the Ka band, a new field for satellite DX experiments.

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140 TELE-audiovision International — The World‘s Largest Digital TV Trade Magazine — 07-08/2013 — www.TELE-audiovision.com

Satellite Reception in the Ka-Band

Did you notice? In the previous is-sue 05-06/2013 of TELE-audiovision the layout of the Ka band article on pages 138 and 139 turned out a bit different than expected. It always showed the same spectrum of Hellas Sat 2 in the Ku and Ka bands, rather than an individual spectrum for each satellite between 39.0°E and 30.0°W.

We’re terribly sorry about that and have prepared the correct pictures in this issue. This time, each satellite comes with the spectrum of the current Ku band and

Ka band (in the 19.7 to 20.2 frequency range). There’s currently only one con-sumer LNB available to receive that par-ticular frequency range, namely the In-verto White Ka.

Just have a look for yourself and in case you’re wondering: Yes, this is actually what you get, or more appropriately, what you don’t get – apart from the TooWay Internet service and a single transponder on Hotbird 13.0°E (which we could not use either) there’s absolutely nothing in the 19.7 to 20.2 GHz range. Zero, nada, rien. When you look at Europe as a whole,

The Same Spectrum – Again and AgainVitor Martins Augusto

In the previous issue 05-06/2013 of TELE-satellite we ran a report about initial attempts at receiving TV signals in the Ka band. This is where the mix-up happened. This time, however, all the spectrums are shown as planned.The original report can be accessed with the following link:http://www.tele-audiovision.com/TELE-audiovision-1305/eng/vitorsworkshop.pdf

this LNB will only be of use in Ireland, where you can receive Soarsat. This pro-vider, however, uses a spot beam which means you’re left in the dark outside Ire-land, even with large antennas.

We also mentioned the DirecTV SL3 LNB in our original article. Of course we tried that LNB as well, but found noth-ing in the 18.3 to 18.8 GHz range. This LNB’s feed is only compatible with circu-lar signals, while satellites beaming their signals to European users transmit linear signals. What’s more, the SL3 feeds don’t simply contain a dielectric which can be replaced. Rather, the feeds are cast and cannot be replaced so exchanged. I’m currently trying to disassemble the entire LNB and then use a standard linear feed from a Ku band LNB. Should this attempt eventually bear fruit I will definitely re-port on it with a special article. So let’s keep our fingers crossed!

As far as the Ka band is concerned we have received first reports of success

142 143TELE-audiovision International — The World‘s Largest Digital TV Trade Magazine — 07-08/2013 — www.TELE-audiovision.com www.TELE-audiovision.com — 07-08/2013 — TELE-audiovision International — 全球发行量最大的数字电视杂志

from the new group of Ka band satellite DXers who have succeed-ed in receiving signals from Ka band transponders in the 21.2 to 22.2 GHz range from Eutelsat 7A (7.0°E) and Eutelsat 16A (16.0°E) in Central Europe. Direct feeds from African providers can be re-ceived from those transponders. What makes matters even more interesting: Those transmissions are free to air, which is great news for people from Africa living in Eu-rope. Channels from Angola, Sen-egal and Congo are available this way, among others.

Unfortunately, however, it’s not all gold:

1) Symbol rates are consistently low, in the 1000 to 2150 range. This means that some receivers may not be able to actually pro-cess those signals. This is one of the reasons why we always look at receiver behaviour with low sym-bol rates in TELE-audiovision test reports.

2) Ka band LNBs for the 21.2 to 22.2 GHz range are currently very hard to get. They are only produced in small numbers for professional applications, which means you might have to accept long delivery times.

One thing is for sure: The Ka band is becoming an ever more interesting reception range and creates a new playground for sat-ellite DXers who are through with everything the C and Ku bands have to offer.

Comparison Ku (10.7-12.7GHz) vsKa (19.7-20.2GHz)Each pair shows the respective satellite in the Ku-Band (10.7 GHz – 12.7 GHz) and in the Ka-Band (19.7 GHz to 20.2 GHz). Notice that a valid signal requires an RF level above approximately -59 dBm.Eutelsat 9A at 9.0E contains 4 transponders in the Ka-Band, which belong to the TooWay satellite based internet service.Using the KWS VAROS 109 it was possible to see a Ka-Band transponder on Hotbird at 13.0E. I received some feedback with a satellite modem, but since I have no valid subscription, I could not further test the reception.