Sudden drop in message rates

[tomvdhorst]

Here’s the userguide for SDR Sharp ( the Windows application).
https://www.rtl-sdr.com/sdrsharp-users-guide/

This is how I’ve setup the system. Make a screenshot of your "normal"operation environment and compare that when you have the interference. Then you have something to compare to.
When measuring do that on the frequency 1090 Mhz and set the gain to max. to broaden your view use the bigger steps in frequency variation.

I’ve tried making screenshots but my system isn’t cooperating at the moment, sorry.

[Dutchyb]

Thank you ( again) for the help and pointing me in to the right direction.

I hope I found the right settings for CubicSDR. Would you please be so kind to check the screenshot I made?

I check the user guide, but it somewhat different from the Mac version,

[wiedehopf]

@Dutchyb

Thank you ( again) for the help and pointing me in to the right direction.

The picture will change a lot when the interference is happening.
If it doesn’t you’ll have to look at other frequencies.

Really it would be best to create a spectrum over all frequencies and then compare that when the interference happens.
That way you could possibly determine the frequency of the interference or at least its main band.

Then you can tune to that and walk around with the laptop to try and find the source (follow where it is stronger).

[tomvdhorst]

That is what you would see in normal conditions indeed. When the interference happens you should try to find its source like wiedehopf described. That will get you closer to the source step by step.

[Dutchyb]

@tomvdhorst @wiedehopf

Thank you both for the help. Will do as described

[Dutchyb]

Hello all,
Maybe, but just maybe I found something that caused my drop in messages and airplanes seen. I did no realise that I hhad not seen this before. Just compared it with an older picture.
Does someone what kind of antenna this is. I find it hard to believe that a tenant is allowed to place his/her antenna on the rooftop especially because there are so many commercial antenna’s.
But please correct me if I am wrong.
Now I have to check with the analyser but the times are getting more and more irregular.

All the help/support is appreciated

,
Thanks

[tomvdhorst]

That looks like an antenna from a mobile phone operator.

Check Locaties antennes in Nederland | Plaatsing antennes | Antennebureau if it is listed there

[Dutchyb]

Thank you very much. Checked the register. Many? 2G, 3G,4G 5G etc antennas. None registered HAM radio.

Guess if it are commercial antennas there is nothing I can do, but the weird thing is still the irregular times. This morning at 9 o’clock.
Would using a blue FA filter DS-B S filter 1090 MHZ bandpass helpful?

[tomvdhorst]

It blocks out unwanted signals so I would certainly go for it

[Dutchyb]

Thank you, will try that tomorrow. Will report back here.

[abcd567]

@Dutchyb

Would using a blue FA filter DS-B S filter 1090 MHZ bandpass helpful?

Like you, I also live in a high rise building in an urban location,with lot of Cell/Mobile antenna on roof top of my building, as well as surrounding buildings, I had poor reception of 1090 MHz due to strong RF signals generated by these Cell phone antennas.

I had to add a FA Blue filter between antenna coax and FA Blue Dongle to improve reception. My 1090 MHz reception falls drastically if I remove FA 1090 MHz Blue Cylendrical filter.

@abcd567

FA 26" antenna + 4ft RG6 coax + FA Filter + ProStick + RPi model2 + Piaware img (SD card) 3.1.0

Spektrum - How-to Speedily Scan RF Noise in band 24MHz ~ 1800MHz

RF Noise At My Location (24 MHz ~ 1800 MHz)

CLICK ON SCREENSHOTS TO SEE LARGER SIZE

CLICK AGAIN TO SEE FULL SIZE (1200 x 780 px)

 

 

 

 

 

 

[wiedehopf]

Do you mean the part at the top or the entire thing?

The speaker looking things that have a direction are mobile phone basestation antennas and cover a certain direction each.

The antenna on the top looks more like a ham / VHF antenna.

Really you can probably fix the issue by putting a filter in front of the uputronics.

[Dutchyb]

@wiedehopf

Really you can probably fix the issue by putting a filter in front of the uputronics.

Thanks for the help. I put the filter in front of the Uptronics at 2 my time. Will have it in place for a few days and report back here

[Dutchyb]

Thank you for the reply. Unfortunately your analyser is for Windows only. I downloaded CubicSDR connected the RTL dongle as shown in the pics above. But I have no idea how to create something like you are showing.
Put the blue FA filter in front of my Uptronics this afternoon around 2 pm