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I am currently trying to observe and obtain data from the meteorological satellites. I have constructed a V-dipole specifically for the 137 MHz and was able to observe the NOAA 15, NOAA 18, and NOAA 19. I was even able to decode some part of it to obtain images.

Recently I found out that Meteor M2 satellite is going to be in my sight today and went out to record the baseband to observe it for later. However, even though I was directing towards the azimuth angles that the satellite needs to be with their elevation angles included, I could not receive anything that might resemble the existence of the satellite. I checked whether I can listen to FM radios as well right before trying to observe the satellite. This seems to point out that it is not about the setup. Also checked that the satellite I was observing is the alive one, not the one that crashed some time ago and there are images in the internet from that satellite approximately one week ago.

Now, I am really curious on why I could not receive even a single part of the signal. Is there anyone with an idea on the topic?

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I checked whether I can listen to FM radios as well right before trying to observe the satellite. This seems to point out that it is not about the setup.

That's not true. Your ability to receive something else is still (like in your last question) not an indication of you being able to receive this.

On the contrary. If the settings, especially the antenna, is right for a local FM station, chances are they are suboptimal for receiving a QPSK satellite downlink. You might actually be blocked by these things you were able to receive properly!

All in all, nobody can tell you why you couldn't hear the satellite. Maybe the space weather was suboptimal, maybe some nearby transmitter saturated your receiver, maybe your gain was too high, or too low, maybe you would have needed an LNA and a proper bandpass filter, maybe you have a faulty antenna connector...

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  • $\begingroup$ Thank you for your ideas, what troubled my mind was that I was able to receive NOAA 15, 18, and 19 satellites with approximately 19 dB SNR. However, I was not able to even observe even something that resembles the Meteor M2 satellite at its frequency. $\endgroup$
    – TEQATAR
    Sep 7, 2020 at 5:37
  • $\begingroup$ After your comment, I retried with a different antenna, one that is better match for a RHCP signal. The weather was clear, adjusted gain for high and low to see if it changes any inputI receive, I have an LNA (inside the HackRF One) an am using that. Right after Meteor M2's pass with max elevation of 60 degrees, I checked whether I can receive RHCP 137 MHz signals with the NOAA 18 passing above me with 45 degrees. I was able to obtain around 20 dB SNR with this configuration. If it were to be any fault of my side, how would I be able to obtain a signal with RCHP from NOAA 18? $\endgroup$
    – TEQATAR
    Sep 8, 2020 at 5:33
  • $\begingroup$ Now based on being able to observe NOAA 18 (137.9125 MHz RHCP) with approximately 20 dB SNR, I think that there does not seem to be a problem with my setup or the atmospheric conditions. Also checked that I was trying to listen to the satellite at its passing time. Now, I am thinking that there might be a temporary shut down, however, there are images pulled from Meteor M2 just the day (yesterday) I tried to receive. Also could not find something on whether it was shut down or not. Now, based on these, it still seems not to resolved why I was not able to observe the signal. $\endgroup$
    – TEQATAR
    Sep 8, 2020 at 5:44

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