TEST REPORT Satellite Reception INFOSAT C/Ku-Band Combifeed with Integrated DiSEqC Switch Thomas Haring and Sylvain Oscul

We have often touched on the C-band subject in TELE-satellite magazine, sometimes with larger antennas and sometimes with smaller ones. One thing was always true: a Combifeed for the ▲ Included in the package: the Com- reception of C-band and Ku-band with integrated DiSEqC switch (to bination LNB with C and Ku-Band switch between bands) as well as 14/18-volt polarization switching LNB in one housing with feed and and 22Khz for switching between the low and high bands has not jumper cable for the built-in DiSEqC been tested by us up to this point. switch.

The Combifeed is offered by fitted on an offset antenna. For INFOSAT in Bangkok, Thailand. our first test we opted to use While the C-band is not in all that a 1.2-meter antenna already much use anymore in , installed on the roof of our it does offer some significant testing facility. Oddly enough, advantages in heavy downpours this antenna symbolizes the or high humidity compared to exact problem that DXer’s face the Ku-band. Receiving both in Europe: if you don’t have a bands with a single Combifeed backyard to call your own and does make quite a bit of sense; have no choice but to install you save the cost of having to your antennas on a steep roof or set up a second antenna. This on your balcony, it is often dif- actually gives us a reason to ficult to consider using a larger once again play around with the antenna. C-band here in Europe since all that is really involved is swap- Thanks to modern C-band and ping out the LNB. Ku-band satellites that transmit with more and more power, a The C/Ku-band feed delivered larger antenna may not neces- from Thailand was designed pri- sarily be required. A 1.2-meter marily for use on prime focus antenna already gives you antennas; although with a little access to thousands of channels ▲ modification ingenuity, it can be from around the world in the A look inside the feed open- ing: clearly recognizable is the dielectric that is necessary for reception of circularly polarized signals. Remove it and you have linear reception.

Ku-band. But as numerous as the Ku-band availability really is, long-distance reception is typically achieved only with C- band and thanks to this new Combifeed, it is quite easy to retrofit your current system for C-band reception.

Since offset antennas are not

▲ The INFOSAT C/Ku-LNBF can be seen here installed on a 1.8m para- bolic antenna.

46 TELE-satellite & Broadband — 08-09/2007 — www.TELE-satellite.com - 47 TELE-satellite & Broadband TELE-satellite We were less successful transponders were also receiv able. when we tried west NSS7 at where 22° receive we 3650R could without only any 08-09/2007 —

www.TELE-satellite.com — www.TELE-satellite.com Rede Gospel and on RCN4108R TV on 4016R; this unfortunately, channel Even was the ImpSat Package from encrypted. Venezuela on 3880R could received be but without any weather reserves. bad A few other - - - -

▲ Our first tests were aimed at also claim a gain of 65dB with a noise figure of 0.3 dB. the C-band so we quickly set up the correct LOF and then had a look at our spectrum analyzer. It indicated located a at 3675R. strong found We and scanchannel quickly starteda signal numerous Russian with plenty of signal channels strength. According to the SatcoDX chan Combifeed has a Ku-band recepKu-band a Combifeedhas tion range of to10.7 12.75 GHz using LOF (local oscillator frequency) values and of10.6 9.75 GHz as well as a C-band range toof GHz3.4 4.2 with an LOF of 5.150 GHz. The specifications MCPC and SCPC transponders were receivable quality. in Especially strong were sufficient nel lists, South American chan nels with relatively high signal strengthcould befound onNSS numberofA west. 40.5° at806 - TELE-satellite editor Thomas Haring aligns the C/ Ku-Band LNBF on a 1.2m offset antenna According to INFOSAT, the Theentire assembly including the antenna to the strong especially EXPRESS A1R satellite at 40° east. C-band were used as receivers. great With expectations, we turned Ku-band LNB; the less sensitive C-band should therefore be no problem. An Eycos S55.12PVR Prodig-5theand signalanalyzer antenna motor was previously aligned using a standard 40mm attempts and some fine tuning adjustments, the feed the was correct position. in a professional solution, butis very it effective and sive. inexpen The installation required dexteritysome afterbutseveral band feeds, a cable clip, available clip, cable a feeds, band electricalfromany wasinstaller, used to secure the Combifeedto the antenna. It’s not exactly normally designed to handle C- problems. On Atlantic Bird taking a closer look towards circularly polarized signals on antenna that happens to be 3 at 5° west we were able to the east. We stumbled across EUTELSAT W4 at 36° east could located at the SatcoDX station easily view 4157L but all the a few surprises: the (unfortu- be received in surprisingly good in Lyon, France. The Combifeed other transponders hovered nately encrypted) AFN pack- quality. is actually designed for this type around the threshold level of age on 906 at 64.2° of antenna. the receiver. Even though on east 4080L was identified by If you remove the dielec- the signal analyzer identified our receiver, the Hope Chan- tric in the feed, then standard And it didn’t take long for us a number of clearly recogniz- nel on at 68.5° Ku-band H/V signals could be to be surprised by the recep- able peaks on the display, they east on 3516V was viewable, received effortlessly. tion results. In the C-band the were still not strong enough Bangla Vision could be seen on Combifeed, fitted with a 17K for actual reception. TELSTAR 10 at 76.5° east on The reasons for the dimin- LNB, could be compared with 4049H and the Express AM1 at ished performance of the Com- a more expensive 15K LNB. As Things looked a little better 40° east delivered a number of bifeed in the Ku-band are fairly our signal analyzer measure- on at 27.5° west Russian channels with plenty of obvious. On the one hand, the ments showed, the Combifeed where we could receive three bad weather reserve. included feed was not designed actually performed better in transponders (3715R, 3831R for use on offset antennas so some frequencies than the and 4048R). On INTELSAT Up until now we were quite you really can’t blame the man- more expensive LNB. 801 at 31.5° west and INTEL- pleased with the results we had ufacturer for this shortfall. SAT 903 at 34.5° west, only gotten; now it was time to take As already seen in the tests one transponder on each was a look at Ku-band reception. On the other hand, the home- with an offset antenna, recep- receivable. made feed holder makes it tion in the Ku-band was some- The strong DTH positions rather difficult to perfectly align what different because the For all the others our antenna such as ASTRA at 19.2° east, the LNB in the focal point of the dielectric had to be removed. was simply too small. The HOTBIRD at 13° east, ASTRA2 antenna. And let’s not forget Then the reception results rep- normally strong EXPRESS A3 at 28.2° east or at that the C-band is much more resented those of a 1.5-meter satellite at 11° west could not 23.5° east could all be received forgiving compared to the Ku- antenna. be received with our 120cm without any problems. We band in terms of antenna align- antenna; the signals that we should mention at this point ment. Overall we can say that it saw on the spectrum analyzer that the INFOSAT C/Ku-band definitely pays to replace your were simply too weak. Combifeed is configured for So let’s switch things around current LNB with the INFOSAT reception of circularly polar- and mount the Combifeed on C/Ku-band Combifeed. Don’t The next step involved ized signals. With that said, the a real 1.8-meter parabolic expect miracles with signal

Signal Measurements using the C/KU-Band Combifeed

EXPRESS AM1 at 40° east, YAMAL 202 at 49° east, NSS 806 at 319.5° east (40.5° west), right-hand polarization left-hand polarization right-hand polarization

Measurement with Standard LNB Measurement with Standard LNB Measurement with Standard LNB

Measurement with C/Ku-Band Combifeed Measurement with C/Ku-Band Combifeed Measurement with C/Ku-Band Combifeed

48 TELE-satellite & Broadband — 08-09/2007 — www.TELE-satellite.com quality in the Ku-band, but for At the same time, it gives you the reception of the strong C a peek at the wonderful world and Ku-band positions, the of C-band even with a small Combifeed would be the perfect antenna without having to elim- choice. inate the Ku-band. TECHNIC DATA Model CKU Digital LNBF Function C/Ku-Band Combifeed

Manufacturer Infosat Intertrade Co., Ltd., 46/22 Moo. 5, Tiwanon Road, Baanmai, Pakkred, Nonthaburi, Thailand

Homepage www.infosats.com Email [email protected] Input Frequency Range Ku: 10.7~11.7 GHz/ 11.7~12.75 GHz linear/circular C: 3.4~4.2 GHz linear/circular

L.O. Frequency Ku: 9.75GHz / 10.6GHz C: 5.150 GHz

Conversion Gain 65 dB Band Switching 22 KHz Polarization Switching 14/18V C/KU-Band Switching DiSEqC Noise Figure 0.3 db (Typ.) Output Connectors 75 Ohm F Type

Some examples of C-band channels that were receivable with the C/Ku-Band

Combifeed: RTG1 on 5° west

VOA via 27.5° west TV Centro on 40.5° west

Rede Gospel on TV5 at NSS806 40.5° west NSS7 22° west

Hope Channel on INTELSAT7 Russian channels 68° east on 40° east