Topics

INMARSAT C-Band Channels

Fred Albertson
 

Hi Patrick, et all,

Attached is a survey of INMARSAT channels in the L-Band visible to me
at MF08oo, in the eastern USA.  The data comes from experimentation,
and research, and may not be absolutely correct, but works for me.  I have
not ventured into C-Band yet, but it is on the horizon.

I can see AMER and AOR-E from here, interestingly enough, from the same
antenna placement, so they show up on the waterfall at the same time.  I am
using the RSP2-Pro receiver, Multipsk (and JAERO),  and a home made 9A4QAV
L-Band patch antenna with a NOOELEC LNA and L-Band SAW filter.

Patrick:  The info on ECG that I provided last May had an error. The AMER
LES for the US and Canada should be as follows:

1539.544MHz    LES-USA

1539.554MHz    LES-Canada

I hope you all find this useful.

Have fun,

Fred

Fred Albertson
Broadway, VA USA



Patrick Lindecker
 

Hello Fred,

 

Thanks for your EGC information. Well noted for the LES USA and Canada.

 

>I have not ventured into C-Band yet, but it is on the horizon.

It’s quite a challenge... And if you have a garden (for the big dish) it will be a big advantage ☺

 

73

Patrick

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de Fred Albertson
Envoyé : vendredi 1 février 2019 23:20
À : multipsk@groups.io
Objet : [multipsk] INMARSAT C-Band Channels

 

Hi Patrick, et all,

Attached is a survey of INMARSAT channels in the L-Band visible to me
at MF08oo, in the eastern USA.  The data comes from experimentation,
and research, and may not be absolutely correct, but works for me.  I have
not ventured into C-Band yet, but it is on the horizon.

I can see AMER and AOR-E from here, interestingly enough, from the same
antenna placement, so they show up on the waterfall at the same time.  I am
using the RSP2-Pro receiver, Multipsk (and JAERO),  and a home made 9A4QAV
L-Band patch antenna with a NOOELEC LNA and L-Band SAW filter.

Patrick:  The info on ECG that I provided last May had an error. The AMER
LES for the US and Canada should be as follows:

1539.544MHz    LES-USA

1539.554MHz    LES-Canada

I hope you all find this useful.

Have fun,

Fred

Fred Albertson
Broadway, VA USA





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Paul Gulliver
 

Hi Fred,
First, thanks for the Inmarsat frequency list, very interesting, regarding AOR-E the list corresponds with my list very well :)
My location is Southern UK and I receive C band from AOR-E (3F5) and L band from Alphasat (4F1) although on occasions I turn my helix around and get L band from AOR-E.

Regarding reception of C band, you should be able to get good usable data from AOR-E using a 1.2m dish whilst Inmarsat are still using a series 3 satellite - the series 4 seems to have much lower power transponders and require a 1.8m or greater dish.
Here in the UK I'm using a 1.1m offset dish for AOR-E and getting good data and feeding Plane Plotter with the data.

My C-Band data displayed on VRS https://flic.kr/p/PcEMvP


Cheers,

Paul


On 01/02/2019 at 22:20, Fred Albertson <albertso@...> wrote:
Hi Patrick, et all,

Attached is a survey of INMARSAT channels in the L-Band visible to me
at MF08oo, in the eastern USA.  The data comes from experimentation,
and research, and may not be absolutely correct, but works for me.  I have
not ventured into C-Band yet, but it is on the horizon.

I can see AMER and AOR-E from here, interestingly enough, from the same
antenna placement, so they show up on the waterfall at the same time.  I am
using the RSP2-Pro receiver, Multipsk (and JAERO),  and a home made 9A4QAV
L-Band patch antenna with a NOOELEC LNA and L-Band SAW filter.

Patrick:  The info on ECG that I provided last May had an error. The AMER
LES for the US and Canada should be as follows:

1539.544MHz    LES-USA

1539.554MHz    LES-Canada

I hope you all find this useful.

Have fun,

Fred

Fred Albertson
Broadway, VA USA




Patrick Lindecker
 

Hello Paul and all,

 

Thanks for your links Paul. For all, note that with almost the same installation , I could not get 1200 bauds AERO data (from the close south of Paris). The necessary dish size must depend on the location.

Below is described my installation.

 

73

Patrick

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de Paul Gulliver
Envoyé : samedi 2 février 2019 10:18
À : multipsk@groups.io
Objet : Re: [multipsk] INMARSAT C-Band Channels

 

Hi Fred,

First, thanks for the Inmarsat frequency list, very interesting, regarding AOR-E the list corresponds with my list very well :)

My location is Southern UK and I receive C band from AOR-E (3F5) and L band from Alphasat (4F1) although on occasions I turn my helix around and get L band from AOR-E.

 

Regarding reception of C band, you should be able to get good usable data from AOR-E using a 1.2m dish whilst Inmarsat are still using a series 3 satellite - the series 4 seems to have much lower power transponders and require a 1.8m or greater dish.

Here in the UK I'm using a 1.1m offset dish for AOR-E and getting good data and feeding Plane Plotter with the data.

 

My C-Band data displayed on VRS https://flic.kr/p/PcEMvP

 

 

Cheers,

 

Paul

 

On 01/02/2019 at 22:20, Fred Albertson <albertso@...> wrote:

Hi Patrick, et all,

Attached is a survey of INMARSAT channels in the L-Band visible to me
at MF08oo, in the eastern USA.  The data comes from experimentation,
and research, and may not be absolutely correct, but works for me.  I have
not ventured into C-Band yet, but it is on the horizon.

I can see AMER and AOR-E from here, interestingly enough, from the same
antenna placement, so they show up on the waterfall at the same time.  I am
using the RSP2-Pro receiver, Multipsk (and JAERO),  and a home made 9A4QAV
L-Band patch antenna with a NOOELEC LNA and L-Band SAW filter.

Patrick:  The info on ECG that I provided last May had an error. The AMER
LES for the US and Canada should be as follows:

1539.544MHz    LES-USA

1539.554MHz    LES-Canada

I hope you all find this useful.

Have fun,

Fred

Fred Albertson
Broadway, VA USA


 




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Paul Gulliver
 

Reception is not helped by the fact the elevation of the satellite (from the UK) changes around 7 degrees over a 12 hour period, this means even with a 1.1m dish the dish has to be re-focused 3 or 4 times over that 12 hour period to keep a usable signal. The larger the dish the more times it would have to be re-focused.

Paul



On 02/02/2019 at 09:30, Patrick Lindecker <f6cte@...> wrote:

Hello Paul and all,

 

Thanks for your links Paul. For all, note that with almost the same installation , I could not get 1200 bauds AERO data (from the close south of Paris). The necessary dish size must depend on the location.


Phil Walls
 

Same in Australia, seems like they all wander. I can only get readable results for roughly 12 hours..give or take an hour.

On Sat, Feb 2, 2019 at 10:09 PM Paul Gulliver <paulg1953@...> wrote:
Reception is not helped by the fact the elevation of the satellite (from the UK) changes around 7 degrees over a 12 hour period, this means even with a 1.1m dish the dish has to be re-focused 3 or 4 times over that 12 hour period to keep a usable signal. The larger the dish the more times it would have to be re-focused.

Paul



On 02/02/2019 at 09:30, Patrick Lindecker <f6cte@...> wrote:

Hello Paul and all,

 

Thanks for your links Paul. For all, note that with almost the same installation , I could not get 1200 bauds AERO data (from the close south of Paris). The necessary dish size must depend on the location.




--
"Learn to live with what you can't rise above"

Fred Albertson
 

Hi, All,

Thanks Paul and the rest of you for your comments on L-Band,
and your prompting me to try C-Band.  I'll get there.  And, yes,
Patrick, I have a "garden."  It is an 8 acre hay field and my look
angle to most of the satellites in question is between 40 and 50
degrees elevation. A good spot.

I'm planning on using a Titanium C-Band LNBF C1W-PLL LNB. 
Any comments?

Thanks,

Fred



Paul Gulliver
 

Fred,

HaHa, a 8 acre field, well you should be able to manage a 10m motorised dish on that - Seriously with the satellites at 40-50 deg elevation you should be ok with a 1.2m dish, at my location AOR-E varies between 11 and 17degrees

The LNB you suggest is a good one, it's the LNB recommended by the Plane Plotter group.

Are you a member of the Plane Plotter group (PP), if not I suggest you join, plenty of advice on setting up C-band and you could join the rest of us in feeding PP and plot aircraft as they go across the oceans (new feeders are alway very welcome)



Cheers

Paul


On 02/02/2019 at 16:15, Fred Albertson <albertso@...> wrote:
Hi, All,

Thanks Paul and the rest of you for your comments on L-Band,
and your prompting me to try C-Band.  I'll get there.  And, yes,
Patrick, I have a "garden."  It is an 8 acre hay field and my look
angle to most of the satellites in question is between 40 and 50
degrees elevation. A good spot.

I'm planning on using a Titanium C-Band LNBF C1W-PLL LNB. 
Any comments?

Thanks,

Fred




Patrick Lindecker
 

Hello Fred,

 

Nice, you will not miss room in your “garden”…

 

>between 40 and 50 degrees elevation.

That’s an advantage. In Paris, 3F5 is at 11° and so it is difficult not to have something between your dish and the satellite.

 

>I'm planning on using a Titanium C-Band LNBF C1W-PLL LNB. 
The C1W-PLL seems to be the best LNBF for this use. However, read this paper:

http://planeplotter.pbworks.com/w/file/fetch/121429833/C-Band_LNB_Mod-word.pdf

However, Hervé and Paul don’t seem to have problems, even if they have not modified their C1W-PLL.

 

73

Patrick

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de Fred Albertson
Envoyé : samedi 2 février 2019 17:15
À : multipsk@groups.io
Objet : Re: [multipsk] INMARSAT C-Band Channels

 

Hi, All,

Thanks Paul and the rest of you for your comments on L-Band,
and your prompting me to try C-Band.  I'll get there.  And, yes,
Patrick, I have a "garden."  It is an 8 acre hay field and my look
angle to most of the satellites in question is between 40 and 50
degrees elevation. A good spot.

I'm planning on using a Titanium C-Band LNBF C1W-PLL LNB. 
Any comments?

Thanks,

Fred



 




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Chris van Lint
 

Hi Paul,

Are you sure you are decoding signals from Inmarst 4F1?  I am decoding 4F1, which is located over central Papua New Guinea and I would have thought the foot print is well beyond your geographical location.  With regards to mitigating the effects of satellite movement, it might be worth considering other means of maintaining the maximum signal possible, in circumstances were we have little or no control over dish movement.  Such measures include using low loss coax, minimising coax cable length and using quality connectors properly fitted.

Cheers,

Chris


At 07:18 PM 2/02/2019, you wrote:
Hi Fred,
First, thanks for the Inmarsat frequency list, very interesting, regarding AOR-E the list corresponds with my list very well :)
My location is Southern UK and I receive C band from AOR-E (3F5) and L band from Alphasat (4F1) although on occasions I turn my helix around and get L band from AOR-E.

Regarding reception of C band, you should be able to get good usable data from AOR-E using a 1.2m dish whilst Inmarsat are still using a series 3 satellite - the series 4 seems to have much lower power transponders and require a 1.8m or greater dish.
Here in the UK I'm using a 1.1m offset dish for AOR-E and getting good data and feeding Plane Plotter with the data.

My C-Band data displayed on VRS https://flic.kr/p/PcEMvP
My dish setup  https://flic.kr/p/2c6rxra


Cheers,

Paul

Paul Gulliver
 

Hi Chris

Of course you are quite right, I'm receiving Alphasat 4F4 at 25deg East, apologies for the confusion

Paul



On 02/02/2019 at 22:57, Chris van Lint <chrisvanlint@...> wrote:
Hi Paul,

Are you sure you are decoding signals from Inmarst 4F1? 

Fred Albertson
 

Hello Paul,

As I mentioned a while ago, I am going to try C-Band AERO.
I finally have my LNA, and I am ready to push on.  I really
appreciate the data you and Patrick have supplied up to this point.

I looked at your dish layout and it looks nice.  Could you give
me the manufacturer's data for the dish, or a source.

Thanks,

Fred

Paul Gulliver
 

Hi Fred,

Before discussing the dish I should say, as I understand, there is quite a difference in output power between the series 3 and series 4 Inmarsat satellites.

I receive C band data from 3F5 and I can just get away with a 1.1 meter dia dish - mine is a generic type bought from ebay for a few UK pounds, however if I was starting again I would go for something a bit larger, say 1.4m dia.

From past discussions on another group (Plane Plotter) I understand that for the series 4 satellites you should be thinking of a 1.8m dia dish as minimum

Another point to consider, the satellites, although geostationary, have a "wobble" which means the elevation varies over a 24 hour period, for me in the UK 3F5 varies between 11deg and 18 deg elevation so the dish has to be aligned 3 or 4 time per day for maximum signal (azimuth also varies but doesn't seem quite so critical) - reference to the satellite tracking program within Multipsk will give you the elevation details for your location.

Hope this helps :)

Cheers,

Paul


On 09/09/2019 at 16:16, Fred Albertson <albertso@...> wrote:
Hello Paul,

As I mentioned a while ago, I am going to try C-Band AERO.
I finally have my LNA, and I am ready to push on.  I really
appreciate the data you and Patrick have supplied up to this point.

I looked at your dish layout and it looks nice.  Could you give
me the manufacturer's data for the dish, or a source.

Thanks,

Fred

Fred Albertson
 

Thank you, Paul,

It does help.  I'll be looking at 4F3 and 3F5 from the
eastern US, so I'll give the size a deep thought.

Great Day,

Fred

David Stark
 

Geostationary satellites travel in a figure 8 path in the sky.  If you aim for the center, or for the largest subcircle, then you should have your best reception most of the time.

-Dave, NF2G

Fred Albertson
 

Hi Paul,

I wrote a while ago that I was going to put together a C-band system. 
You provided a lot of valuable info that I considered as I developed
my setup.

It took a while, but I'm "on-the-air" with a 120cm Prime Focus dish
and C1W-PLL LNB.

I have no problems getting data from the 4F3 satellite, but I can't find
the signals from the 3F5 bird.

Do you have a solid ACARS downlink frequency from 3F5 that I can search for
as I position the antenna?

Here are some frequencies I have found on the 4F3. All are listed as the translated
frequency:

1531.125 - 1200 data

1534.975 - 10500 burst - Good ACARS data

1535.200 - 10500 burst

1535.800 to 820 - 1200 burst

Thanks,

Fred






Paul Gulliver
 

Hi Fred,

Good to hear you are receiving C band data from 4F3,

Unfortunately I don't know of any continuous c-band signals on 3F5 - that would make life too easy, the 2 most active frequencies for me are 1533.81 and 1534.36 both 10500bps burst. There are other frequencies that have 10500bps burst but the data is infrequent so I tend not to bother monitoring them.
The laptop I use is not very powerful, if I try to monitor too many frequencies it tends to crash.

Remember these frequencies are approximate, exact values depending on your LNB oscillator frequency - with temperature drift these frequencies can change up to 30KHz during the day especially if we have a chilly night followed by a warm day - I think my LNB must be particularly bad for temperature drift.

If all else fails, make a small helix along theses lines  https://uhf-satcom.com/satellite-reception/l-band  and swap it for the LNB and align the dish with L band signals (aero on 1545.0 to 1545.3MHz for 3F5) theses are fairly strong and continuous so it makes alignment easier

Hope this info helps

Paul


On 20/03/2020 at 22:00, Fred Albertson <albertso@...> wrote:
Hi Paul,

I wrote a while ago that I was going to put together a C-band system. 
You provided a lot of valuable info that I considered as I developed
my setup.

It took a while, but I'm "on-the-air" with a 120cm Prime Focus dish
and C1W-PLL LNB.

I have no problems getting data from the 4F3 satellite, but I can't find
the signals from the 3F5 bird.

Do you have a solid ACARS downlink frequency from 3F5 that I can search for
as I position the antenna?

Here are some frequencies I have found on the 4F3. All are listed as the translated
frequency:

1531.125 - 1200 data

1534.975 - 10500 burst - Good ACARS data

1535.200 - 10500 burst

1535.800 to 820 - 1200 burst

Thanks,

Fred







Paul Gulliver
 

One thing I forgot, and this is just a shot in the dark, it's possible the signal polarity may be different between the series 3 and series 4 birds - try reversing the polarity on the LNB either by voltage or changing the slab orientation in the LNB itself

Paul


On 21/03/2020 at 10:08, Paul Gulliver via Groups.Io <paulg1953@...> wrote:
Hi Fred,

Good to hear you are receiving C band data from 4F3,

Unfortunately I don't know of any continuous c-band signals on 3F5 - that would make life too easy, the 2 most active frequencies for me are 1533.81 and 1534.36 both 10500bps burst. There are other frequencies that have 10500bps burst but the data is infrequent so I tend not to bother monitoring them.
The laptop I use is not very powerful, if I try to monitor too many frequencies it tends to crash.

Remember these frequencies are approximate, exact values depending on your LNB oscillator frequency - with temperature drift these frequencies can change up to 30KHz during the day especially if we have a chilly night followed by a warm day - I think my LNB must be particularly bad for temperature drift.

If all else fails, make a small helix along theses lines  https://uhf-satcom.com/satellite-reception/l-band  and swap it for the LNB and align the dish with L band signals (aero on 1545.0 to 1545.3MHz for 3F5) theses are fairly strong and continuous so it makes alignment easier

Hope this info helps

Paul


On 20/03/2020 at 22:00, Fred Albertson <albertso@...> wrote:
Hi Paul,

I wrote a while ago that I was going to put together a C-band system. 
You provided a lot of valuable info that I considered as I developed
my setup.

It took a while, but I'm "on-the-air" with a 120cm Prime Focus dish
and C1W-PLL LNB.

I have no problems getting data from the 4F3 satellite, but I can't find
the signals from the 3F5 bird.

Do you have a solid ACARS downlink frequency from 3F5 that I can search for
as I position the antenna?

Here are some frequencies I have found on the 4F3. All are listed as the translated
frequency:

1531.125 - 1200 data

1534.975 - 10500 burst - Good ACARS data

1535.200 - 10500 burst

1535.800 to 820 - 1200 burst

Thanks,

Fred








Fred Albertson
 

Thank you so much, Paul.

I'll try your suggestions as soon as the local weather turns nice
again.  Windy now.  No good for the dish.  Too much like a sail!

Having a known freq will assist immensely, as will the idea of
spotting using the L-band signals. 

I had tried the polarity reversal, but with no positive results. 
I think I am still off target.

I'll keep you posted.

Be safe in this terrible time.

Fred