Topics

Bias Tee for C- & L-Band AERO decoding #aero

Roland Fechter
 

Hallo,
May I again ask for your advice, please ?
I wish to receive mainly 1200 Baud data - 1500 Baud seems to be out of my reach here in Germany as I lack the space for putting up the seemingly required 1.1 m to 1.8 m ? dish.
I am mainly interested in "catching" far-out aircraft position reports.- I already use VDL with its limited range.
My RX is the Funcube prof. plus dongle. Length of my coax cable abt. 15m. I plan to use also my existing 80cm dish either with the Dutch Helix or with the C1W pll C-band LNBF.
I have both - the  RFhamdesign  LHCP Helix dish feed tuned to 1545-1546 MHz
as well as the Titanium C1W-PLL Wideband C-band LNBF which requires a DC-voltage of 11 - 20 Vdc.
 Unfortunately I do not know yet which voltage is required by the Dutch LHCP Helix dish feed, but I guess ist 11-20 Vdc as well ?
As my Funcube has an inbuilt Bias Tee turning out I think 5V only, I guess that this voltage is too weak meaning for me another piece of equipment,
namely a separate Bias T delivering a DC-voltage of between 11 to 20 Vdc. Is my assumption correct ?
If so - please advise which suitable Bias Tee YOU use - plus the name and email address of its supplier/s. An "economical" version would do for me
as I have already spent more than enough towards one day receiving AERO data.
 I definitely would like to stick to my Funcube - as an alternative SDR I also have a DVB T DAB FM TCXO dongle.
In plain words - using the Funcube with its  inbuilt Bias Tee  de-activated, linking it to a suitable external DC-voltage source, ie a suitable Bias T
which injects the necessary 11-20Vdc voltage into my coax cable.
I should be most grateful for your kind suggestions.Thanks in advance,
Regards,
Roland

Chris van Lint
 

Roland,

I cannot help but think that you are confusing some of the issues.

Let  us take a step back and acknowledge that there are two completely different issues: Inmarsat L-Band AERO transmissions and Inmarsast C-Band transmissions.
 I would strongly suggest that for the moment you forget about the C-Band, until you get the L-Band going properly.

·         The L-Band does NOT require a dish

·         You can use either a helix or a patch

·         It would be useful to have an LNA for either the helix or the patch antenna

·         The helix or patch needs to be properly polarised.  I understand that in your case the
        satellite transmits a LHCP (Left Hand Circularly Polarised) signal.

.·         If your helix is the RFHam design eshailsat, it is most unlikely to include an LNA, as it is         quoted at 300W transmit power.  Therefore the question regarding the supply voltage is  irrelevant.

·         This helix is LHCP, so if you use it in a dish feed it will receive RHCP signals, which is not        suitable for the satellite you are trying to receive signals from.

·         The patch or helix does not require exact focusing on the satellite, however the more         accurate your feed  is “focused” on the satellite, the stronger your signal.

·         You refer to “Bauds” . Strictly speaking the Baud unit is the number of times a signal in     a communications channel changes state.  In the case of the Inmarsat AERO       transmissions we are dealing with signals in which x-number (e.g. 1200) zeros or ones   are transmitted in one second and the correct terminology is bps (Bits Per Second).

·         You state that 1500 baud seems to be out of your reach.  I presume this is a typo and         should read: “10500 baud (bps)”

·         I am not sure why you wish to focus on 1200 bps signals  On the L-Band most signals are
        600bps or 10500bps.  Both are easily decoded with a patch and on 4F1 there is only one  1200bps signal.

·         Be aware that some channels will lock when you tune to them with Multipsk, but they do not    necessarily transmit any ACARS data.  Also some may only be “fill in” or “SU Sys Table”          transmissions.  Once you get the hang of tuning onto the signal you will find a channel that    transmits ACRAS data.

·         All transmissions on the L-Band are continuous – there are NO burst transmissions.
-------------------------------------------------------------------------------------------------------------------------------
The C-Band

·         For receiving C-Band signals you will need a device which down-converts the 3.6Ghz    signals from the satellite to a frequency you receiver can handle (around 1.5GHz).  Such a      device is called an LNB (Low Noise Block).

·         The Titanium C1-PLL Wide-Band LNB is intended for receiving TV signals and it is      designed to respond to linearly polarised signals.  The LNB can be used for circular    polarisation by inserting a dielectric slab in the feed horn, which is usually supplied with the        LNB. The polarisation is selected by changing the LNB feed voltage - 11.5 – 14V for     Vertical or RHCP and 16 – 20V for Horizontal or LHCP.

·         You will need a bias-tee to provide that voltage.  I believe Mr. Gulliver has advised that your       satellite is LHCP, so you will need to power the LNB with 18V

·         Make sure you turn OFF the bias voltage supply in your radio (Funcube), as it may damage      your SDR.  Bothe the Funcube and the DVB T DAB FM TCXO dongle are perfect for   receiving signals between 1.5 - 1.7 GHz.


·         You can use the “splitter” provided in a satellite receiver to supply the correct LNB voltage.  I     do not know how much these satellite receivers cost, but if you do not have one you can         either construct your own, if you have the facilities or you can buy a bias-tee on ebay for a   few dollars. https://www.ebay.com/sch/i.html?_from=R40&_nkw=bias-tee&_sacat=0&rt=nc&LH_FS=1   If you buy a bias-tee you will still need a DC power supply to    supply the required 18V.

·         It DOES NOT MAKE SENSE to use an LNA between the receiver and LNB.  All active        devices generate unwanted noise and unless your coax feed cable >30 meters an   additional LNA will probably do more harm than good, as it may overload the SDR input.

.       The Titanium LNB has an output impedance of 75 Ohms, whereas the input impedance        of the Funcube is 50 Ohms.  I recommend that you use 75 Ohm low loss satellite cable    right to the receiver. (the input impedance of the "dongle" is 75 Ohms).

·         On the C-Band I suggest you start with decoding 10500 bps burst signals first, as they are    easiest to decode.  The 1200bps burst are a bit more tricky, because they are generally         weaker and require more accurate tuning.  Use a band-width od 15kHz on youe SDR for 1   0500bps burst signals and 3kHz for 1200bps burst channels.




The At 04:28 AM 17/12/2018, you wrote:

Hallo,
May I again ask for your advice, please ?
I wish to receive mainly 1200 Baud data - 1500 Baud seems to be out of my reach here in Germany as I lack the space for putting up the seemingly required 1.1 m to 1.8 m ? dish.
I am mainly interested in "catching" far-out aircraft position reports.- I already use VDL with its limited range.
My RX is the Funcube prof. plus dongle. Length of my coax cable abt. 15m. I plan to use also my existing 80cm dish either with the Dutch Helix or with the C1W pll C-band LNBF.
I have both - the  RFhamdesign  LHCP Helix dish feed tuned to 1545-1546 MHz
as well as the Titanium C1W-PLL Wideband C-band LNBF which requires a DC-voltage of 11 - 20 Vdc.
 Unfortunately I do not know yet which voltage is required by the Dutch LHCP Helix dish feed, but I guess ist 11-20 Vdc as well ?
As my Funcube has an inbuilt Bias Tee turning out I think 5V only, I guess that this voltage is too weak meaning for me another piece of equipment,
namely a separate Bias T delivering a DC-voltage of between 11 to 20 Vdc. Is my assumption correct ?
If so - please advise which suitable Bias Tee YOU use - plus the name and email address of its supplier/s. An "economical" version would do for me
as I have already spent more than enough towards one day receiving AERO data.
 I definitely would like to stick to my Funcube - as an alternative SDR I also have a DVB T DAB FM TCXO dongle.
In plain words - using the Funcube with its  inbuilt Bias Tee  de-activated, linking it to a suitable external DC-voltage source, ie a suitable Bias T
which injects the necessary 11-20Vdc voltage into my coax cable.
I should be most grateful for your kind suggestions.Thanks in advance,
Regards,
Roland

Patrick Lindecker
 

Hello to all,

 

In my small experience in L band, I could receive 600 and 1200 bauds transmissions with a 60 cm dish (+ helix antenna) or a Patch antenna, but no 10500 bauds transmissions. For theses last ones, I needed a 1 m dish  (+ helix antenna).

 

With my RTL-SDR V3, the LNA (+ 1500/1550 MHz filter) was indispensable (without it, I had no reception at all).

 

73

Patrick

 

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de Chris van Lint
Envoyé : lundi 17 décembre 2018 06:29
À : multipsk@groups.io
Objet : Re: [multipsk] Bias Tee for C- & L-Band AERO decoding #aero

 

Roland,

I cannot help but think that you are confusing some of the issues.

Let  us take a step back and acknowledge that there are two completely different issues: Inmarsat L-Band AERO transmissions and Inmarsast C-Band transmissions.
 I would strongly suggest that for the moment you forget about the C-Band, until you get the L-Band going properly.

·         The L-Band does NOT require a dish

·         You can use either a helix or a patch

·         It would be useful to have an LNA for either the helix or the patch antenna

·         The helix or patch needs to be properly polarised.  I understand that in your case the
        satellite transmits a LHCP (Left Hand Circularly Polarised) signal.

.·         If your helix is the RFHam design eshailsat, it is most unlikely to include an LNA, as it is         quoted at 300W transmit power.  Therefore the question regarding the supply voltage is  irrelevant.

·         This helix is LHCP, so if you use it in a dish feed it will receive RHCP signals, which is not        suitable for the satellite you are trying to receive signals from.

·         The patch or helix does not require exact focusing on the satellite, however the more         accurate your feed  is “focused” on the satellite, the stronger your signal.

·         You refer to “Bauds” . Strictly speaking the Baud unit is the number of times a signal in     a communications channel changes state.  In the case of the Inmarsat AERO       transmissions we are dealing with signals in which x-number (e.g. 1200) zeros or ones   are transmitted in one second and the correct terminology is bps (Bits Per Second).

·         You state that 1500 baud seems to be out of your reach.  I presume this is a typo and         should read: “10500 baud (bps)”

·         I am not sure why you wish to focus on 1200 bps signals  On the L-Band most signals are
        600bps or 10500bps.  Both are easily decoded with a patch and on 4F1 there is only one  1200bps signal.

·         Be aware that some channels will lock when you tune to them with Multipsk, but they do not    necessarily transmit any ACARS data.  Also some may only be “fill in” or “SU Sys Table”          transmissions.  Once you get the hang of tuning onto the signal you will find a channel that    transmits ACRAS data.

·         All transmissions on the L-Band are continuous – there are NO burst transmissions.
-------------------------------------------------------------------------------------------------------------------------------
The C-Band

·         For receiving C-Band signals you will need a device which down-converts the 3.6Ghz    signals from the satellite to a frequency you receiver can handle (around 1.5GHz).  Such a      device is called an LNB (Low Noise Block).

·         The Titanium C1-PLL Wide-Band LNB is intended for receiving TV signals and it is      designed to respond to linearly polarised signals.  The LNB can be used for circular    polarisation by inserting a dielectric slab in the feed horn, which is usually supplied with the        LNB. The polarisation is selected by changing the LNB feed voltage - 11.5 – 14V for     Vertical or RHCP and 16 – 20V for Horizontal or LHCP.

·         You will need a bias-tee to provide that voltage.  I believe Mr. Gulliver has advised that your       satellite is LHCP, so you will need to power the LNB with 18V

·         Make sure you turn OFF the bias voltage supply in your radio (Funcube), as it may damage      your SDR.  Bothe the Funcube and the DVB T DAB FM TCXO dongle are perfect for   receiving signals between 1.5 - 1.7 GHz.


·         You can use the “splitter” provided in a satellite receiver to supply the correct LNB voltage.  I     do not know how much these satellite receivers cost, but if you do not have one you can         either construct your own, if you have the facilities or you can buy a bias-tee on ebay for a   few dollars. https://www.ebay.com/sch/i.html?_from=R40&_nkw=bias-tee&_sacat=0&rt=nc&LH_FS=1   If you buy a bias-tee you will still need a DC power supply to    supply the required 18V.

·         It DOES NOT MAKE SENSE to use an LNA between the receiver and LNB.  All active        devices generate unwanted noise and unless your coax feed cable >30 meters an   additional LNA will probably do more harm than good, as it may overload the SDR input.

.       The Titanium LNB has an output impedance of 75 Ohms, whereas the input impedance        of the Funcube is 50 Ohms.  I recommend that you use 75 Ohm low loss satellite cable    right to the receiver. (the input impedance of the "dongle" is 75 Ohms).

·         On the C-Band I suggest you start with decoding 10500 bps burst signals first, as they are    easiest to decode.  The 1200bps burst are a bit more tricky, because they are generally         weaker and require more accurate tuning.  Use a band-width od 15kHz on youe SDR for 1   0500bps burst signals and 3kHz for 1200bps burst channels.




The At 04:28 AM 17/12/2018, you wrote:

Hallo,
May I again ask for your advice, please ?
I wish to receive mainly 1200 Baud data - 1500 Baud seems to be out of my reach here in Germany as I lack the space for putting up the seemingly required 1.1 m to 1.8 m ? dish.
I am mainly interested in "catching" far-out aircraft position reports.- I already use VDL with its limited range.
My RX is the Funcube prof. plus dongle. Length of my coax cable abt. 15m. I plan to use also my existing 80cm dish either with the Dutch Helix or with the C1W pll C-band LNBF.
I have both - the  RFhamdesign  LHCP Helix dish feed tuned to 1545-1546 MHz
as well as the Titanium C1W-PLL Wideband C-band LNBF which requires a DC-voltage of 11 - 20 Vdc.
 Unfortunately I do not know yet which voltage is required by the Dutch LHCP Helix dish feed, but I guess ist 11-20 Vdc as well ?
As my Funcube has an inbuilt Bias Tee turning out I think 5V only, I guess that this voltage is too weak meaning for me another piece of equipment,
namely a separate Bias T delivering a DC-voltage of between 11 to 20 Vdc. Is my assumption correct ?
If so - please advise which suitable Bias Tee YOU use - plus the name and email address of its supplier/s. An "economical" version would do for me
as I have already spent more than enough towards one day receiving AERO data.
 I definitely would like to stick to my Funcube - as an alternative SDR I also have a DVB T DAB FM TCXO dongle.
In plain words - using the Funcube with its  inbuilt Bias Tee  de-activated, linking it to a suitable external DC-voltage source, ie a suitable Bias T
which injects the necessary 11-20Vdc voltage into my coax cable.
I should be most grateful for your kind suggestions.Thanks in advance,
Regards,
Roland




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Chris van Lint
 

Hi Patrick,

I do not use VRS, but I note that Pauk has already given you the benefit of his expertise on this software.
Your other comments make perfect sense.  One of the disadvantages of NOT using a dish is that the antenna is not very directional and is subject to interference from other RF sources.  I live about 2km away from a mountain on which all of Brisbane's TV antennas are mounted plus a host of others 5G antennas, microwave links etc.  The harmonics, sub-harmonics and mix components of these transmissions, which run into 100's of kWs some times cause havoc even at times to the C-Band signal on the dish.
Your comments underline that it is impossible to make definitive statements based on ones own experience.  Reception conditions vary from satellite to satellite.  I am particularly intrigued by your comment that you receive 1200 bps signals.  On 4F1 there is only one 1200bps signal (that I can find), but lots of channels on 10500 bps and 600bps. 

73, VK4CVLAt 04:04 AM 18/12/2018, you wrote:

Hello to all,
 
In my small experience in L band, I could receive 600 and 1200 bauds transmissions with a 60 cm dish (+ helix antenna) or a Patch antenna, but no 10500 bauds transmissions. For theses last ones, I needed a 1 m dish  (+ helix antenna).
 
With my RTL-SDR V3, the LNA (+ 1500/1550 MHz filter) was indispensable (without it, I had no reception at all).
 
73
Patrick
 
 
De : multipsk@groups.io [ mailto:multipsk@groups.io] De la part de Chris van Lint
Envoyé : lundi 17 décembre 2018 06:29
À : multipsk@groups.io
Objet : Re: [multipsk] Bias Tee for C- & L-Band AERO decoding #aero
 

Paul Gulliver
 

Hi Chris,

Regarding 1200bps channels on L-Band, on the 3F5 satellite at 54degW I have found 4 containing useful data, a couple of them interest me as they contain transmissions from the USAF C5 Galaxy aircraft, one of the few military aircraft that use 1200bps. In addition I've found six 600bps and three 10500bps channels. Most military traffic confined to the slower bit rate

My findings are the same as Patrick, only the 600 and 1200 bps can be received without a dish (using a patch or small helix) so I usually use a dish for all L-band and C-band reception

Cheers,

Paul




On 18/12/2018 at 05:05, Chris van Lint <chrisvanlint@...> wrote:
Hi Patrick,

I do not use VRS, but I note that Pauk has already given you the benefitof his expertise on this software.
Your other comments make perfect sense.  One of the disadvantages ofNOT using a dish is that the antenna is not very directional and issubject to interference from other RF sources.  I live about 2kmaway from a mountain on which all of Brisbane's TV antennas are mountedplus a host of others 5G antennas, microwave links etc.  Theharmonics, sub-harmonics and mix components of these transmissions, whichrun into 100's of kWs some times cause havoc even at times to the C-Bandsignal on the dish.
Your comments underline that it is impossible to make definitivestatements based on ones own experience.  Reception conditions varyfrom satellite to satellite.  I am particularly intrigued by yourcomment that you receive 1200 bps signals.  On 4F1 there is only one1200bps signal (that I can find), but lots of channels on 10500 bps and600bps. 

73, VK4CVLAt 04:04 AM 18/12/2018, you wrote:

Patrick Lindecker
 

Hello Chris,

 

>I am particularly intrigued by your comment that you receive 1200 bps signals.

I don’t know how many 600 and 1200 bauds there were, coming from the 3F2 satellite. But here is what I received (with a Patch antenna) on a 48 KHz bandwidth (SDR spectrum). The thin ones are 600 bauds and the others 1200 bauds.

 

 

Yes it seems to have big differences between satellites and particularly relatively to the power: I had not been able to monitor 4A-F4 transmissions which were very weak, whereas the transmissions from 3F2 were OK.

 

73

Patrick

 

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de Chris van Lint
Envoyé : mardi 18 décembre 2018 06:05
À : multipsk@groups.io
Objet : Re: [multipsk] Bias Tee for C- & L-Band AERO decoding #aero

 

Hi Patrick,

I do not use VRS, but I note that Pauk has already given you the benefit of his expertise on this software.
Your other comments make perfect sense.  One of the disadvantages of NOT using a dish is that the antenna is not very directional and is subject to interference from other RF sources.  I live about 2km away from a mountain on which all of Brisbane's TV antennas are mounted plus a host of others 5G antennas, microwave links etc.  The harmonics, sub-harmonics and mix components of these transmissions, which run into 100's of kWs some times cause havoc even at times to the C-Band signal on the dish.
Your comments underline that it is impossible to make definitive statements based on ones own experience.  Reception conditions vary from satellite to satellite.  I am particularly intrigued by your comment that you receive 1200 bps signals.  On 4F1 there is only one 1200bps signal (that I can find), but lots of channels on 10500 bps and 600bps. 

73, VK4CVLAt 04:04 AM 18/12/2018, you wrote:

Hello to all,
 
In my small experience in L band, I could receive 600 and 1200 bauds transmissions with a 60 cm dish (+ helix antenna) or a Patch antenna, but no 10500 bauds transmissions. For theses last ones, I needed a 1 m dish  (+ helix antenna).
 
With my RTL-SDR V3, the LNA (+ 1500/1550 MHz filter) was indispensable (without it, I had no reception at all).
 
73
Patrick
 
 
De : multipsk@groups.io [ mailto:multipsk@groups.io] De la part de Chris van Lint
Envoyé : lundi 17 décembre 2018 06:29
À : multipsk@groups.io
Objet : Re: [multipsk] Bias Tee for C- & L-Band AERO decoding #aero
 




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www.avast.com


Ralf Bender
 

Looks like that I'm in a not bad position for L-Band decoding now. This is my waterfall since a few weeks.
10 x 600 bauds and 1 x 1200 bauds. The dish of 60 cm is in my room at the first floor in the moment. Not outside, like last year.
I see some 10500 bauds also, but very weak.
Decoding with Multipsk Test Version 3, direct connected to my NooElec NESDR SMArTee XTR SDR works perfect.  
With NooElec Low Noise Amplifier (LNA) and Saw-Filter-Modul for outernet and inmarsat.



Position of my dish while taking the screenshot of my waterfall:

gerrykuk
 

Hi Ralf I see you are using NooElec NESDR SMArTee XTR SDR mine does not work on normal I get something on i or q but even thats not right but at least it starts Im on W10 tried usb drivers a load of times and still think it is pulling the wrong driver one google said got it going using tcp mine refuses 1234 address 73 Gerry

On 18/12/2018 21:17:05, Ralf Bender via Groups.Io <rlfbender@...> wrote:

Looks like that I'm in a not bad position for L-Band decoding now. This is my waterfall since a few weeks.
10 x 600 bauds and 1 x 1200 bauds. The dish of 60 cm is in my room at the first floor in the moment. Not outside, like last year.
I see some 10500 bauds also, but very weak.
Decoding with Multipsk Test Version 3, direct connected to my NooElec NESDR SMArTee XTR SDR works perfect.  
With NooElec Low Noise Amplifier (LNA) and Saw-Filter-Modul for outernet and inmarsat.



Position of my dish while taking the screenshot of my waterfall:

Attachments:

Ralf Bender
 
Edited

Hi Gerry, I'm also on W10. Did you installed the Zadig driver (https://zadig.akeo.ie/) ? That was my way to get it work. 73, Ralf

P.S.
Installation Guide: https://support.nooelec.com/hc/en-us/articles/360005298053-NESDR-Installation-Guide

gerrykuk
 

Hi Ralf Tried Zadic still comes up with     Cannot access rtl device    will keep trying  73 Gerry

On 18/12/2018 21:57:29, Ralf Bender <rlfbender@...> wrote:

[Edited Message Follows]

Hi Gerry, I'm also on W10. Did you installed the Zadig driver (https://zadig.akeo.ie/) ? That was my way to get it work. 73, Ralf

P.S.
Installation Guide: https://support.nooelec.com/hc/en-us/articles/360005298053-NESDR-Installation-Guide

Patrick Lindecker
 

Nice waterfall Ralf! Several dB better that my reception with a Patch antenna. But not sufficient for 10500 bauds transmissions decoding, I suppose (based on my experience with a 60 cm dish) ?

 

With the Patch, I saw (or to be honest, let’s say “guess”) 10500 bauds transmissions very very weak.

 

73

Patrick

 

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de Ralf Bender via Groups.Io
Envoyé : mardi 18 décembre 2018 22:17
À : multipsk@groups.io
Objet : Re: [multipsk] Bias Tee for C- & L-Band AERO decoding #aero

 

Looks like that I'm in a not bad position for L-Band decoding now. This is my waterfall since a few weeks.
10 x 600 bauds and 1 x 1200 bauds. The dish of 60 cm is in my room at the first floor in the moment. Not outside, like last year.
I see some 10500 bauds also, but very weak.
Decoding with Multipsk Test Version 3, direct connected to my NooElec NESDR SMArTee XTR SDR works perfect.  
With NooElec Low Noise Amplifier (LNA) and Saw-Filter-Modul for outernet and inmarsat.



Position of my dish while taking the screenshot of my waterfall:

Attachments:




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www.avast.com


Roland Fechter
 

very impressive, Ralf !

As I am going to get the same Nooelec LNA plus the Nooelec Smartee sdr I now face the big obstacle regarding the right feed for my also available 80cm dish.

Your nice picture shows your dish with your Helix feed snug on it - a true expert job !

As I have two "left hands" and only very superficial knowledge I wonder if you could be so kind as to provide me - against payment of course - with this so sweet looking helical feed and its feed mounting.

My situation is quite complicated:

My antenna-dish is abt. 15m away outside on my balcony - if I remember correctly the helical feed must get the right voltage through the coax cable - given my long 15m cable and the "meager" 4.5 V output of the Smarttee sdr I wonder if this can be done in my case. By the way: do you connect the Nooelec LNA right onto the dongle, ie right behind the dongle ?

Sorry to bother you - hope you dont mind my questions !

I look forward to your reply.

Regards,

Roland


Am 18.12.2018 um 22:17 schrieb Ralf Bender via Groups.Io:

Looks like that I'm in a not bad position for L-Band decoding now. This is my waterfall since a few weeks.
10 x 600 bauds and 1 x 1200 bauds. The dish of 60 cm is in my room at the first floor in the moment. Not outside, like last year.
I see some 10500 bauds also, but very weak.
Decoding with Multipsk Test Version 3, direct connected to my NooElec NESDR SMArTee XTR SDR works perfect.  
With NooElec Low Noise Amplifier (LNA) and Saw-Filter-Modul for outernet and inmarsat.



Position of my dish while taking the screenshot of my waterfall:

Attachments:


Chris van Lint
 

Hello Patrick / all

Given the general consensus that there are significant differences in the channel allocations on the Inmarsat L-Band system, I decided to create a couple of screenshots showing the channel distribution.

Satellite: Inmarsat 4F1 L-Band

Note:  Even though a  channel may be marked "idle" it is possible that at times ACARS messages come through.  I just gave up after waiting several minutes.

P-Channel = P_R_ channel control ISU

Cheers,

VK4CVL

Ralf Bender
 

You are right, Patrick. I can see the 10500 bauds transmissions, not only guess :-), but it isn't enough for decoding. 
BTW: I also see 10 600 bauds transmissions at 1539 MHz (IOR ) and were able to decode the EGC with Multipsk. 

Ralf Bender
 

Hello Roland,

many thanks for the flowers :-), but I didn't really think it's an expert job. So please don't be angry, but I think it's good enough for me at home, but nothing I would do for others. I'm so sorry.

Regards
Ralf 

Patrick Lindecker
 

Ralf, effectively the EGC transmissions are perfect.

 

73

Patrick

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de Ralf Bender
Envoyé : mercredi 19 décembre 2018 18:29
À : multipsk@groups.io
Objet : Re: [multipsk] Bias Tee for C- & L-Band AERO decoding #aero

 

You are right, Patrick. I can see the 10500 bauds transmissions, not only guess :-), but it isn't enough for decoding. 
BTW: I also see 10 600 bauds transmissions at 1539 MHz (IOR ) and were able to decode the EGC with Multipsk. 




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