Topics

Is reception of METEOR M 2 presently possible ?

Patrick Lindecker
 

Hello to all,

 

I would like to monitor the METEOR M 2 satellite on 137.1 MHz (I know the passes of this satellite), but I’m not able to see its trace on my Sdr waterfall.  

Are there persons in this group who have recently succeed monitoring this satellite,  and if so with which equipment?

I tried with a RTL/SDR dongle (V3) and with a RSP1A. I have neither 137 MHZ LNA nor 137 MHz filter. I made a (provisional) V-dipole for 137 MHz.

 

73

Patrick

 

 

 

 

 

 

 

 




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Tiziano Gmail
 

Hy Patrick,

is very easy decode the digital signal of meteor m2. I can use a turnstile antenna for 137 Mhz as  well the one for 144 mhz. One normal SDR receiver.. with a free program that you can find in internet..

Tiziano Pattaro
Cell +393460406074


Il giorno 15 giu 2020, alle ore 22:39, Patrick Lindecker <f6cte@...> ha scritto:



Hello to all,

 

I would like to monitor the METEOR M 2 satellite on 137.1 MHz (I know the passes of this satellite), but I’m not able to see its trace on my Sdr waterfall.  

Are there persons in this group who have recently succeed monitoring this satellite,  and if so with which equipment?

I tried with a RTL/SDR dongle (V3) and with a RSP1A. I have neither 137 MHZ LNA nor 137 MHz filter. I made a (provisional) V-dipole for 137 MHz.

 

73

Patrick

 

 

 

 

 

 

 

 




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L'absence de virus dans ce courrier électronique a été vérifiée par le logiciel antivirus Avast.
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Patrick Lindecker
 

Hello Tiziano,

 

RR for the antenna.

>One normal SDR receiver

Which precisely?, with a 137 MHz LNA ? a 137 MHz filter?

 

Do you receive it precisely on 137.1 MHz ? (+/- several KHz for the Doppler I suppose) or an another frequency?

 

73

Patrick

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de Tiziano Gmail
Envoyé : lundi 15 juin 2020 22:48
À : multipsk@groups.io
Objet : Re: [multipsk] Is reception of METEOR M 2 presently possible ?

 

Hy Patrick,

 

is very easy decode the digital signal of meteor m2. I can use a turnstile antenna for 137 Mhz as  well the one for 144 mhz. One normal SDR receiver.. with a free program that you can find in internet..

Tiziano Pattaro

Cell +393460406074

 



Il giorno 15 giu 2020, alle ore 22:39, Patrick Lindecker <f6cte@...> ha scritto:



Hello to all,

 

I would like to monitor the METEOR M 2 satellite on 137.1 MHz (I know the passes of this satellite), but I’m not able to see its trace on my Sdr waterfall.  

Are there persons in this group who have recently succeed monitoring this satellite,  and if so with which equipment?

I tried with a RTL/SDR dongle (V3) and with a RSP1A. I have neither 137 MHZ LNA nor 137 MHz filter. I made a (provisional) V-dipole for 137 MHz.

 

73

Patrick

 

 

 

 

 

 

 

 

 


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DSP Engr
 

I usually see Meteor M2 pass by with LRPT on 137.900 MHz and ~120kHz bandwidth. The LRPT signal is QPSK 72k symbols/s with a 144kbps data rate. If you should get a color image decoder going for LRPT and MultiPSK, I am glad to test it.

DSP Engr
 

Meteor M2-2 just passed by a little while ago. I can confirm it was not transmitting on 137.1 MHz or 137.9 MHz. According to the article here, it was hit by a micrometeoroid and Is no longer transmitting LRPT: https://www.rtl-sdr.com/meteor-m-n2-2-weather-satellite-updates-no-more-137-mhz-lrpt-l-x-band-working-in-daylight/ . Will check Meteor M2 when I get a chance. Recent blogs indicate Meteor M2 is supposed to be on 137.1 Mhz when transmitting.

DSP Engr
 

Meteor M2 is transmitting the LRPT signal. Confirmed that it is on 137.10 MHz. Equipment: RSP1A, 20 dB 0.6dB NF preamplifier with 2nd order band pass filter, and QFH antenna. Antenna construction is here: https://www.sdrplay.com/community/viewtopic.php?f=5&t=2529 

Patrick Lindecker
 

Hello,

 

Thanks for the information. The signal received is very good on your SdR spectrum.

 

Without preamplifier nor filter (which is my configuration), are you able to distinguish the signal?

 

73

Patrick

 

 

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de DSP Engr
Envoyé : mardi 16 juin 2020 04:28
À : multipsk@groups.io
Objet : Re: [multipsk] Is reception of METEOR M 2 presently possible ?

 

Meteor M2 is transmitting the LRPT signal. Confirmed that it is on 137.10 MHz. Equipment: RSP1A, 20 dB 0.6dB NF preamplifier with 2nd order band pass filter, and QFH antenna. Antenna construction is here: https://www.sdrplay.com/community/viewtopic.php?f=5&t=2529 




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Tiziano Gmail
 

Patrick,

on my station I have Turnstile antenna, without pre-amplifier, 35 meters of RG58, and I can receive the signal very well..

IK3COB - Tiziano

Il 16/06/2020 10:22, Patrick Lindecker ha scritto:

Hello,

 

Thanks for the information. The signal received is very good on your SdR spectrum.

 

Without preamplifier nor filter (which is my configuration), are you able to distinguish the signal?

 

73

Patrick

 

 

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de DSP Engr
Envoyé : mardi 16 juin 2020 04:28
À : multipsk@groups.io
Objet : Re: [multipsk] Is reception of METEOR M 2 presently possible ?

 

Meteor M2 is transmitting the LRPT signal. Confirmed that it is on 137.10 MHz. Equipment: RSP1A, 20 dB 0.6dB NF preamplifier with 2nd order band pass filter, and QFH antenna. Antenna construction is here: https://www.sdrplay.com/community/viewtopic.php?f=5&t=2529 




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Patrick Lindecker
 

With which SdR receiver(s) Tiziano ?

 

73

Patrick

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de Tiziano Gmail
Envoyé : mardi 16 juin 2020 12:15
À : multipsk@groups.io
Objet : Re: [multipsk] Is reception of METEOR M 2 presently possible ?

 

Patrick,

on my station I have Turnstile antenna, without pre-amplifier, 35 meters of RG58, and I can receive the signal very well..

IK3COB - Tiziano

Il 16/06/2020 10:22, Patrick Lindecker ha scritto:

Hello,

 

Thanks for the information. The signal received is very good on your SdR spectrum.

 

Without preamplifier nor filter (which is my configuration), are you able to distinguish the signal?

 

73

Patrick

 

 

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de DSP Engr
Envoyé : mardi 16 juin 2020 04:28
À : multipsk@groups.io
Objet : Re: [multipsk] Is reception of METEOR M 2 presently possible ?

 

Meteor M2 is transmitting the LRPT signal. Confirmed that it is on 137.10 MHz. Equipment: RSP1A, 20 dB 0.6dB NF preamplifier with 2nd order band pass filter, and QFH antenna. Antenna construction is here: https://www.sdrplay.com/community/viewtopic.php?f=5&t=2529 

 


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Tiziano Gmail
 

SDR RX


NOTCH FM BAND



Tiziano Pattaro
Cell +393460406074




Il giorno 16 giu 2020, alle ore 13:35, Patrick Lindecker <f6cte@...> ha scritto:



With which SdR receiver(s) Tiziano ?

 

73

Patrick

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de Tiziano Gmail
Envoyé : mardi 16 juin 2020 12:15
À : multipsk@groups.io
Objet : Re: [multipsk] Is reception of METEOR M 2 presently possible ?

 

Patrick,

on my station I have Turnstile antenna, without pre-amplifier, 35 meters of RG58, and I can receive the signal very well..

IK3COB - Tiziano

Il 16/06/2020 10:22, Patrick Lindecker ha scritto:

Hello,

 

Thanks for the information. The signal received is very good on your SdR spectrum.

 

Without preamplifier nor filter (which is my configuration), are you able to distinguish the signal?

 

73

Patrick

 

 

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de DSP Engr
Envoyé : mardi 16 juin 2020 04:28
À : multipsk@groups.io
Objet : Re: [multipsk] Is reception of METEOR M 2 presently possible ?

 

Meteor M2 is transmitting the LRPT signal. Confirmed that it is on 137.10 MHz. Equipment: RSP1A, 20 dB 0.6dB NF preamplifier with 2nd order band pass filter, and QFH antenna. Antenna construction is here: https://www.sdrplay.com/community/viewtopic.php?f=5&t=2529 

<image001.jpg>

 


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Patrick Lindecker
 

TKS Tiziano. So you use a Turnstile antenna, a standard RTL/SDR dongle and a FM stop band. It seems simple. I will make a 137 MHz filter and will see if I receive something.

 

73

Patrick

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de Tiziano Gmail
Envoyé : mardi 16 jui
n 2020 13:44
À : multipsk@groups.io
Objet : Re: [multipsk] Is reception of METEOR M 2 presently possible ?

 

SDR RX

 

NOTCH FM BAND

 

 

Tiziano Pattaro

Cell +393460406074

 

 

 



Il giorno 16 giu 2020, alle ore 13:35, Patrick Lindecker <f6cte@...> ha scritto:



With which SdR receiver(s) Tiziano ?

 

73

Patrick

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de Tiziano Gmail
Envoyé : mardi 16 juin 2020 12:15
À : multipsk@groups.io
Objet : Re: [multipsk] Is reception of METEOR M 2 presently possible ?

 

Patrick,

on my station I have Turnstile antenna, without pre-amplifier, 35 meters of RG58, and I can receive the signal very well..

IK3COB - Tiziano

Il 16/06/2020 10:22, Patrick Lindecker ha scritto:

Hello,

 

Thanks for the information. The signal received is very good on your SdR spectrum.

 

Without preamplifier nor filter (which is my configuration), are you able to distinguish the signal?

 

73

Patrick

 

 

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de DSP Engr
Envoyé : mardi 16 juin 2020 04:28
À : multipsk@groups.io
Objet : Re: [multipsk] Is reception of METEOR M 2 presently possible ?

 

Meteor M2 is transmitting the LRPT signal. Confirmed that it is on 137.10 MHz. Equipment: RSP1A, 20 dB 0.6dB NF preamplifier with 2nd order band pass filter, and QFH antenna. Antenna construction is here: https://www.sdrplay.com/community/viewtopic.php?f=5&t=2529 

<image001.jpg>

 


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DSP Engr
 

Patrick - The RSP1A already has a built-in FM notch filter, just turn it on in SDRuno. Note that your V-Dipole antenna is linearly polarized and the LRPT signal from Meteor M2 is RHCP. So you will have a 3dB loss due to the linear polarization to start with. I would expect that with a linearly polarized V-Dipole antenna placed outdoors, no preamplifier, and an RSP1A, you would be able to see the Meteor M2 LRPT signal using SDRuno as the satellite passes overhead or near overhead. An RHCP antenna, such as a QFH or Turnstile, will produce better results.

Patrick Lindecker
 

With the RSP1A, I see a very weak signal and nothing with the RTL/SDR. I hope that a 137 MHz filter will improve the signal to noise ratio.

I will make this one:

http://lna4all.blogspot.com/2015/11/diy-137-mhz-wx-sat-bp-filter.html

 

73

Patrick

 

 

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de DSP Engr
Envoyé : mardi 16 juin 2020 21:31
À : multipsk@groups.io
Objet : Re: [multipsk] Is reception of METEOR M 2 presently possible ?

 

Patrick - The RSP1A already has a built-in FM notch filter, just turn it on in SDRuno. Note that your V-Dipole antenna is linearly polarized and the LRPT signal from Meteor M2 is RHCP. So you will have a 3dB loss due to the linear polarization to start with. I would expect that with a linearly polarized V-Dipole antenna placed outdoors, no preamplifier, and an RSP1A, you would be able to see the Meteor M2 LRPT signal using SDRuno as the satellite passes overhead or near overhead. An RHCP antenna, such as a QFH or Turnstile, will produce better results.




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DSP Engr
 
Edited

Patrick - If you are not seeing interference, then the band pass filter you are proposing will likely not help and, in fact, may actually lower the signal level by 1 to 2 dB (insertion loss). If you can post an image of the LRPT signal you are seeing, that would help in better understanding what is going on. The key settings used for the RSP1A here are 2MHz sample rate and decimation of 4, FM with 120 kHz bandwidth. The FM notch filter of the RSP1A was not used as I have a band pass filter in the preamplifier for 137 MHz. I think your ability to bring in a strong LRPT signal is primarily dependent upon how well the antenna works, the loss in the path from the antenna to the SDR, and the noise figure on the front end of the SDR. Currently, your reception of the LRPT signal from Meteor M2 is marginal. According to the article here, the NF for the RSP1A is 3.4dB at 137 MHz: https://www.sdrplay.com/wp-content/uploads/2018/01/RSP1A-Technical-Information-R1P1.pdf . If you are barely seeing the signal with the RSP1A, then if your other SDR has a higher front end noise figure, you may not see the signal at all under the same conditions with the other SDR. So with 3dB loss at the antenna from linear polarization, the ability to receive the signal well becomes more challenging. Using a QFH antenna or a turnstile antenna that is right hand circularly polarized will help quite a bit. Adding a preamplifier with a significantly lower front end noise figure to then raise the signal level so that it is less impacted by the noise figure of the front end of the SDR, will also help the overall SNR quite a bit. If you can show an image of the V-Dipole you are using with dimensions of the elements, that will also help give an idea what is happening. When receiving low level satellite signals, every dB counts.

df6dbf@...
 

I listen since a few days to NOAA and METEOR M2, using a QFH-Antenna and an RTLSDR Dongle with an Raspberry PI3. (take a look at github: https://github.com/reynico/raspberry-noaa)

Antenna is not on her final place (actual in the attic) and i need a preamp to.

https://twitter.com/df6dbf/status/1272821635104505858

73s Holger, DF6DBF

Patrick Lindecker
 

Hello,

 

Here, in city, there is always a certain level of noise and interferences. I think that a 137 Mhz filter will help a bit (much more certainly for the RTL/SDR).

 

Thanks for the interesting data about RSP1A.

 

Here about is the antenna that I use from a balcony:

 

adams_v-dipole-500x375

73

Patrick

 

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de DSP Engr
Envoyé : mardi 16 juin 2020 23:23
À : multipsk@groups.io
Objet : Re: [multipsk] Is reception of METEOR M 2 presently possible ?

 

[Edited Message Follows]

Patrick - If you are not seeing interference, then the band pass filter you are proposing will likely not help and, in fact, may actually lower the signal level by tenths of a dB (insertion loss). If you can post an image of the LRPT signal you are seeing, that would help in better understanding what is going on. The key settings used for the RSP1A here are 2MHz sample rate and decimation of 4, FM with 120 kHz bandwidth. The FM notch filter of the RSP1A was not used as I have a band pass filter in the preamplifier for 137 MHz. I think your ability to bring in a strong LRPT signal is primarily dependent upon how well the antenna works, the loss in the path from the antenna to the SDR, and the noise figure on the front end of the SDR. Currently, your reception of the LRPT signal from Meteor M2 is marginal. According to the article here, the NF for the RSP1A is 3.4dB at 137 MHz: https://www.sdrplay.com/wp-content/uploads/2018/01/RSP1A-Technical-Information-R1P1.pdf . If you are barely seeing the signal with the RSP1A, then if your other SDR has a higher front end noise figure, you may not see the signal at all under the same conditions with the other SDR. So with 3dB loss at the antenna from linear polarization, the ability to receive the signal well becomes more challenging. Using a QFH antenna or a turnstile antenna that is right hand circularly polarized will help quite a bit. Adding a preamplifier with a significantly lower front end noise figure to then raise the signal level so that it is less impacted by the noise figure of the front end of the SDR, will also help the overall SNR quite a bit. If you can show an image of the V-Dipole you are using with dimensions of the elements, that will also help give an idea what is happening.




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Patrick Lindecker
 

Thanks for the description of your equipment Holger.

I will have a look on these QFH antennas.

 

73

Patrick

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de df6dbf@...
Envoyé : mardi 16 juin 2020 17:39
À : multipsk@groups.io
Objet : Re: [multipsk] Is reception of METEOR M 2 presently possible ?

 

I listen since a few days to NOAA and METEOR M2, using a QFH-Antenna and an RTLSDR Dongle with an Raspberry PI3. (take a look at github: https://github.com/reynico/raspberry-noaa)

Antenna is not on her final place (actual in the attic) and i need a preamp to.

https://twitter.com/df6dbf/status/1272821635104505858

73s Holger, DF6DBF




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Tiziano Gmail
 

Hi Patrick,

I tried the “V” antenna for satellite 📡 on 137 Mhz, but no good result.. 🤷‍♂️ is better the one for 144 Mhz..; by the way, the best result is with an Turn Stile antenna.. Look NOAA18 of yesterday evening..





Tiziano Pattaro
Cell +393460406074


Il giorno 17 giu 2020, alle ore 13:02, Patrick Lindecker <f6cte@...> ha scritto:



Hello,

 

Here, in city, there is always a certain level of noise and interferences. I think that a 137 Mhz filter will help a bit (much more certainly for the RTL/SDR).

 

Thanks for the interesting data about RSP1A.

 

Here about is the antenna that I use from a balcony:

 

<image001.png>

73

Patrick

 

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de DSP Engr
Envoyé : mardi 16 juin 2020 23:23
À : multipsk@groups.io
Objet : Re: [multipsk] Is reception of METEOR M 2 presently possible ?

 

[Edited Message Follows]

Patrick - If you are not seeing interference, then the band pass filter you are proposing will likely not help and, in fact, may actually lower the signal level by tenths of a dB (insertion loss). If you can post an image of the LRPT signal you are seeing, that would help in better understanding what is going on. The key settings used for the RSP1A here are 2MHz sample rate and decimation of 4, FM with 120 kHz bandwidth. The FM notch filter of the RSP1A was not used as I have a band pass filter in the preamplifier for 137 MHz. I think your ability to bring in a strong LRPT signal is primarily dependent upon how well the antenna works, the loss in the path from the antenna to the SDR, and the noise figure on the front end of the SDR. Currently, your reception of the LRPT signal from Meteor M2 is marginal. According to the article here, the NF for the RSP1A is 3.4dB at 137 MHz: https://www.sdrplay.com/wp-content/uploads/2018/01/RSP1A-Technical-Information-R1P1.pdf . If you are barely seeing the signal with the RSP1A, then if your other SDR has a higher front end noise figure, you may not see the signal at all under the same conditions with the other SDR. So with 3dB loss at the antenna from linear polarization, the ability to receive the signal well becomes more challenging. Using a QFH antenna or a turnstile antenna that is right hand circularly polarized will help quite a bit. Adding a preamplifier with a significantly lower front end noise figure to then raise the signal level so that it is less impacted by the noise figure of the front end of the SDR, will also help the overall SNR quite a bit. If you can show an image of the V-Dipole you are using with dimensions of the elements, that will also help give an idea what is happening.




Avast logo

L'absence de virus dans ce courrier électronique a été vérifiée par le logiciel antivirus Avast.
www.avast.com



Tiziano Gmail
 

Hi Patrick,

I tried the “V” antenna for satellite 📡 on 137 Mhz, but no good result.. 🤷‍♂️ is better the one for 144 Mhz..; by the way, the best result is with an Turn Stile antenna.. Look NOAA18 of yesterday evening..





Tiziano Pattaro
Cell +393460406074


Il giorno 17 giu 2020, alle ore 13:02, Patrick Lindecker <f6cte@...> ha scritto:



Hello,

 

Here, in city, there is always a certain level of noise and interferences. I think that a 137 Mhz filter will help a bit (much more certainly for the RTL/SDR).

 

Thanks for the interesting data about RSP1A.

 

Here about is the antenna that I use from a balcony:

 

<image001.png>

73

Patrick

 

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de DSP Engr
Envoyé : mardi 16 juin 2020 23:23
À : multipsk@groups.io
Objet : Re: [multipsk] Is reception of METEOR M 2 presently possible ?

 

[Edited Message Follows]

Patrick - If you are not seeing interference, then the band pass filter you are proposing will likely not help and, in fact, may actually lower the signal level by tenths of a dB (insertion loss). If you can post an image of the LRPT signal you are seeing, that would help in better understanding what is going on. The key settings used for the RSP1A here are 2MHz sample rate and decimation of 4, FM with 120 kHz bandwidth. The FM notch filter of the RSP1A was not used as I have a band pass filter in the preamplifier for 137 MHz. I think your ability to bring in a strong LRPT signal is primarily dependent upon how well the antenna works, the loss in the path from the antenna to the SDR, and the noise figure on the front end of the SDR. Currently, your reception of the LRPT signal from Meteor M2 is marginal. According to the article here, the NF for the RSP1A is 3.4dB at 137 MHz: https://www.sdrplay.com/wp-content/uploads/2018/01/RSP1A-Technical-Information-R1P1.pdf . If you are barely seeing the signal with the RSP1A, then if your other SDR has a higher front end noise figure, you may not see the signal at all under the same conditions with the other SDR. So with 3dB loss at the antenna from linear polarization, the ability to receive the signal well becomes more challenging. Using a QFH antenna or a turnstile antenna that is right hand circularly polarized will help quite a bit. Adding a preamplifier with a significantly lower front end noise figure to then raise the signal level so that it is less impacted by the noise figure of the front end of the SDR, will also help the overall SNR quite a bit. If you can show an image of the V-Dipole you are using with dimensions of the elements, that will also help give an idea what is happening.




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Patrick Lindecker
 

>I tried the “V” antenna for satellite 📡 on 137 Mhz, but no good result..

Thanks for the information Tiziano (and the nice pictures).

 

73

Patrick

 

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de Tiziano Gmail
Envoyé : mercredi 17 juin 2020 13:16
À : multipsk@groups.io
Objet : Re: [multipsk] Is reception of METEOR M 2 presently possible ?

 

Hi Patrick,

 

I tried the “V” antenna for satellite 📡 on 137 Mhz, but no good result.. 🤷‍♂️ is better the one for 144 Mhz..; by the way, the best result is with an Turn Stile antenna.. Look NOAA18 of yesterday evening..

 

 

 

Tiziano Pattaro

Cell +393460406074

 



Il giorno 17 giu 2020, alle ore 13:02, Patrick Lindecker <f6cte@...> ha scritto:



Hello,

 

Here, in city, there is always a certain level of noise and interferences. I think that a 137 Mhz filter will help a bit (much more certainly for the RTL/SDR).

 

Thanks for the interesting data about RSP1A.

 

Here about is the antenna that I use from a balcony:

 

<image001.png>

73

Patrick

 

 

De : multipsk@groups.io [mailto:multipsk@groups.io] De la part de DSP Engr
Envoyé : mardi 16 juin 2020 23:23
À : multipsk@groups.io
Objet : Re: [multipsk] Is reception of METEOR M 2 presently possible ?

 

[Edited Message Follows]

Patrick - If you are not seeing interference, then the band pass filter you are proposing will likely not help and, in fact, may actually lower the signal level by tenths of a dB (insertion loss). If you can post an image of the LRPT signal you are seeing, that would help in better understanding what is going on. The key settings used for the RSP1A here are 2MHz sample rate and decimation of 4, FM with 120 kHz bandwidth. The FM notch filter of the RSP1A was not used as I have a band pass filter in the preamplifier for 137 MHz. I think your ability to bring in a strong LRPT signal is primarily dependent upon how well the antenna works, the loss in the path from the antenna to the SDR, and the noise figure on the front end of the SDR. Currently, your reception of the LRPT signal from Meteor M2 is marginal. According to the article here, the NF for the RSP1A is 3.4dB at 137 MHz: https://www.sdrplay.com/wp-content/uploads/2018/01/RSP1A-Technical-Information-R1P1.pdf . If you are barely seeing the signal with the RSP1A, then if your other SDR has a higher front end noise figure, you may not see the signal at all under the same conditions with the other SDR. So with 3dB loss at the antenna from linear polarization, the ability to receive the signal well becomes more challenging. Using a QFH antenna or a turnstile antenna that is right hand circularly polarized will help quite a bit. Adding a preamplifier with a significantly lower front end noise figure to then raise the signal level so that it is less impacted by the noise figure of the front end of the SDR, will also help the overall SNR quite a bit. If you can show an image of the V-Dipole you are using with dimensions of the elements, that will also help give an idea what is happening.

 


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