It sounds like the Thuraya GMPRS service is more sensitive to antenna orientation than the "1722" 9.6k dialup service.
I continue to use my 7100 phone using 9.6k dialup, and the antenna is not at all critical. Sure, it gives the strongest signal when pointed directly at the satellite (which lies in the south east direction, from Europe) but it works well in other orientations too.
During my tests in 2009 I found GMPRS very unreliable but could not work out why. Reading between the lines of Thuraya's "monkey-script" support emails I got the feeling that they knew the service was crap but could not say so. But today is 4 years later! If this was a real problem, and it was a normal cellular network, they would have gone bust a long time ago.
For the external antenna, you need the car docker for the XT which is a bulky piece of plastic that costs 400 €. The XT got an female antenna connector on the back which needs a sort of bayonet male pin that I was not able to find -- otherwise I would have built a docker myself. An expert built the cable to connect the docker to the external antenna (standard SMA).
I noticed that it takes about 10 minutes for GmPRS to work but once it works (you get an IP), it is reliable with the external antenna. I use it for a lot of things including radar images, strikes, etc. and I have built my own web app. I have never tried the traditional dialup, it is too slow for image transfer anyway and much more expensive.
I am enquiring now about getting a hotspot and external antenna to try out.
In order to "try out" the antenna, you need to drill 5 holes in your airframe. My initial experiments were done in my convertible car where I strapped the antenna onto the head rest. After some driving at different speeds (car limited to 250kph = 140 knots) I got a good feeling and drilled the holes into the airframe and installed the antenna. My requirement was to eliminate all ugly cabling and have no loose devices floating around, nothing in the way. So I built a custom console that I mounted onto the dome. Another requirement was to do without a PC and use standard smartphones and tablets, thus the wifi hotspot.
I don't think there is anything comparable to Thuraya GmPRS. 64kbit at $1.1/MB is pretty spectacular in the satellite internet world.
It seems the best signal with the XT is when the axis of the antenna is oriented south-east at say 45 degrees above the horizon.
Yes I will "try out" everything on the ground first.
First of all I will see whether the GMPRS service is better than when I last tried it a couple of years ago. It wasn't practically useful then. However I am living near the western edge of coverage.
It seems the phone docking station comes with the external antenna so it is not an additional eur400 to potentially go down the drain if the system proves to be impracticable .....
It seems the phone docking station comes with the external antenna so it is not an additional eur400 to potentially go down the drain if the system proves to be impracticable .....
There is the docker without antenna for 300 €
And there is the docker with external antenna for 400 € which is a POS magnet mount dome antenna that is about 5 times larger than it looks. I ordered it as well but sent it back right away.
You need an aircraft antenna which is about $500
Current antenna price is about $440 and I will do the import. I have placed an order today, but I'm still able to change it.
I like to Iridium/Thuraya antenna.. Does it work well?
My commander has the MLX770 already installed .. waiting for the IFD540 .. and for it to support it. I am seriously thinking of the upcoming Aeroplus solution or the upcoming Iphone sleeve (the second one that will support Gmprs)
the upcoming Iphone sleeve (the second one that will support Gmprs)
It won't have a connector for an external antenna, thus useless in a cockpit.
waiting for the IFD540
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"I like to Iridium/Thuraya antenna.. Does it work well?
My commander has the MLX770 already installed .. waiting for the IFD540 .. and for it to support it. I am seriously thinking of the upcoming Aeroplus solution or the upcoming Iphone sleeve (the second one that will support Gmprs)"
Thuraya and Iridium are two different systems:
Thuraya:
Iridium:
Did you really install the expensive MLX770 without having a suitable display (EX500, EX600 etc.) available in the aircraft?
