New video about methanol maser observations

[Eduard Mol]

Hi all, 

Just uploaded a new video about observing methanol masers to my youtube channel: https://youtu.be/769lwlAhejA?si=w7LEjdl6HjVUfxa8 

This one took quite a while to finish, as you can probably guess from the intro. In particular the data processing was quite complicated due to strong RFI from satellites. 

Best regards, 

Eduard

[Alex P]

Hello Eduard,

PHENOMENAL Effort !

You are Truly an Outstanding Young Scientist 

Satellite RFI : would it be possible to record these signals on a second system with a much broader beam-width antenna 

that would thus not contain your maser info but used as a data set for RFI removal ? ( or would freq matching be too difficult ? )

Regards,

Alex Pettit

[b alex pettit jr]

OR : a second feed offset from the first collecting background/satellite info but spatially shifted from the target ?

[Eduard Mol]

Thanks Alex!!

Well, the RFI is a tricky problem. The satellites are transients, they quickly pass through the beam (or the sidelobes, after all these things can be as bright as the Sun at 12GHz…). If there are only satellites in the beam or sidelobes for a fraction of the time it’s easy enough to filter out the affected spectra. However, what I’m seeing now is that in certain parts of the sky there are satellites in the beam more often than not. 

If you had a second antenna with a wider beam it would see these satellites more often (maybe even continuously). However, these are not necessarily the same satellites. I don’t know if the RFI is similar enough between different satellites that you would be able to subtract the RFI sample. 

Op zo 12 apr 2026 om 21:40 schreef 'b alex pettit jr' via Society of Amateur Radio Astronomers <sara...@googlegroups.com>

OR : a second feed offset from the first collecting background/satellite info but spatially shifted from the target ?

Satellite RFI : would it be possible to record these signals on a second system with a much broader beam-width antenna 

that would thus not contain your maser info but used as a data set for RFI removal ? ( or would freq matching be too difficult ? )

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[b alex pettit jr]

Eduard,

Send me a few IFaverage *.txt files with the RFI & let me run a few median/mean filter tests on them..

I'll send you graphic / csvfile results if I find something useful.

Thanks,

Alex

====================================================

[shinichir...@gmail.com]

Dear Eduard,

It’s an excellent video!
Your pointing method using the 1‑m dish with a finder scope, as well as the motor‑controlled dish‑drive mechanism, is truly impressive — especially since I only have a fixed‑mount dish!

 S. Asayama

[Adrian]

Eduard,

  An excellent video.  I also think your satellite RFI analysis of the problem for being able to eliminate their signal is correct. The two main culprits are OneWeb and Starlink with thousands of satellites all downlinking wideband OFMD, multi‑carrier beam signals hundreds of MHz wide with blocks of multiple overlapping channels per sat. and all occupying the  10.7–12.7 GHz band. So as you mentioned, their LEO rapid transits and with them practically crossing any azimuth and meridian at any moment it is nearly impossible to avoid their continued  presence in your main antenna beamwidth or due to the strength of their signals even interfering through antenna side lobes.  So the only alternative for MeOH maser observations looks like developing the receiving equipment for the 6.7 GHz line where even here one might still have to contend with the encroaching new  Wi-Fi 6E and Wi-Fi 7  network signals. Oh well!

Adrian

[Jason Burnfield]

Lisa and I enjoyed watching your new video! Keep 'em coming!

[Dimitry UA3AVR]

Nice video, Eduard ... congrats

пятница, 10 апреля 2026 г. в 22:14:45 UTC+3, Eduard Mol: