About the coverage

In a way, that is normal, ads-b is line of sight. The higher they fly, the further away you can track them, terrain permitting.

That sounds good, in most cases that has the biggest impact on better reception. Strange that it did not have any effect.

Apart from the distance and number of aircraft, the message rate is also a sign of better reception, are you aware if that has improved?

It has the right SMA connector. Does it say anything on the side? If it is 2 or 3m, I guess it is okay, although most HAMs will probably disagree here :slight_smile: .

The RTLSDRBlog-dongle is one of the better, and the store you linked is the official one from them on aliexpress.

Really not sure what the issue is, here.

Maybe you really need a filter, like the dark blue FA filter or the one from radarbox. You could check the “Do I need a filter” thread, there are tips and instructions to create a heatmap that lets you show which signals the antenna picks up.

Or create a simple homebrew antenna out of coax cable, for comparison. Or if possible, move the whole setup to a different location, maybe a friends house. Some people also created a mobile versions with a Pi Zero.

What type of Pi are you using. @wiedehopf also wrote some nice scripts to check wether the dongle might not get enough voltage, although that would manifest in a different way.

1 Like

Thank you for answer.
Will try that setup location change in the near future. I am using Pi 4. Will try to generate the heatmap also. But I sure need your help guys to decode it :blush:

To be honest I did not even payed a notice on the message rate :see_no_evil:

This is the best that I have got out of the thing so far. All those domestic flights stay inside of the 50NM circle tho.

That somewhat suggests terrain around your location is blocking reception.
Are there hills around you?

Could also be that you’re getting strong interference, in that case you need a filter, i’d recommend getting this:
New Product: RTL-SDR Blog 1090 MHz ADS-B LNA

With the LNA added your gear might be called a proper car, ferrari is still something else and would mean a name brand antenna and LMR 400, maybe an airspy SDR :wink:

Running a scan for intereference as described here might be enlightening:
Do I Need A Filter?


are you using an usb extension cable?
is your Raspberry powered with a good cable and a good power source?


No USB extension.
Power source and cable are Raspberry original

Yes of course you are right. There are many ways and levels where you can go. And I sure don´t want to go there :slight_smile:
What I meant was, that I feel this setup could do better. As I mentioned earlier the antenna does not matter in my case. As long as there is something sticked to that SDR (by that I mean dipole antenna with any lenght and any orientation) It will get me the same range.
That makes me to feel just stupid to purchase 1060-1120Mhz 5,5dB antenna and have the same results. :thinking:
So that was the 1-st gear meaning. The ferrari was indeed a exaggeration, lets keep that as Pinto then :grinning:

Make it a Volvo using the LNA i mentioned, it’s not too expensive ($30).
Not sure how long shipping is at the moment though.

I’ve looked and it doesn’t seem to be terrain.
The most likely issue then is interference.

That might be true across antennas.

Anyhow the LNA has 3 filters builtin and is what really completes the rtl-sdr v3 for ADS-B.
Without that, the FA ProStick Plus or the green AirNav stick (having an integrated LNA and one filter) fare better than the v3.

1 Like

@wiedehopf @biekerc Just completed the scan, results below:

1 Like


Cell/ Mobile phone tower nearby.
Interference both by UHF TV (800 Mhz) and GSM900.
You definitely need a filter!



Looks like a filter would not do any harm, in any case.

I still feel a bit suspicious about that antenna (or the cable). The range really is a bit low, not sure if all that can really be caused by strong nearby cell phone signals…

1 Like

I understand. My brain said the same. That´s why i ordered the 1060-1120Mhz antenna with the “quality” cable. I don´t have any instruments to confirm the products quality. Feedback from the other users had been great, so this is the only indicator for me at the moment. It may be possible that I have been sold empty PVC tube with the N-Female connector. I did not open the tube because it is sealed(for the weather) but this special antenna does not perform any better than my dipole that come with the SDR. And as I previously mentioned many times it does not matter how much I retract the rods on dipole or if I connect the “special” antenna. Results are practically same. The “special” antenna gives me about 10 more NM of coverage.

Considering the inverse square law, there is a significant change in signal from 50 to 60 nmi.

The interference on 800 MHz is just brutal.
I’m 99% certain that’s your issue.

1 Like

@wiedehopf Thank you for reply.
As i mentioned before that I don´t know anything about radio stuff and as embarrassed I am at the moment. :see_no_evil: (but I´m good in some other stuff :smiley: ) Can you please give me any suggestion,what kind of filter should I ask from local electronics shop or link to the product that I need.

Little backstory of me if someone is interested.
“I have one child 5-Yo boy, a wife and an old cat. I work on engineering level at metal industry. My hobby is quite similar that I do my working hours, 3D modelling and printing. Weekends go past as usual(male persons know). At the moment I have more than enough gadgets that my wife can handle in our household. Maybe closer to my retirement I will become HAM person. But for now flight tracking got my attention and it´s something that I just like to do to spend my free time.If it does not suit for me then I will give the Pi to my kid and he can build a robot or something(masturbator when in suitable age) else out of it”


already did that.

It will require some changes on the pi, are you comfortable with that?
How to is available and detailed to turn on the bias-t of the rtl-sdr v3.

1 Like

If there are instructions I´m cool. Without them I would be in trouble I guess.
And I lost you at the second line ! :see_no_evil:


1 Like

Some punctuation would have made that line a little clearer, but what he said was that there is a detailed “How To” available to teach you how to enable the “bias-t” (really, Bias-tee) functionality on the RTL-SDR version 3 dongle.

Basically that dongle has the ability to “push” DC power up the coax antenna cable in order to provide power to an amplifier installed at the antenna (vs needing to run a separate cable and power supply) - but you need to enable the function with software commands.

In that case, your installation would look like (antenna > amp >>>>>> cable >>>>>> receiver/dongle > RPi)

At least, I think that’s what was meant.

Most people start out with a $10 generic dongle - you started with a much better one.
Many people have bought a WiFi extension cable with the wrong SMA plug (RP-SMA) on it - you got the right cable.
Many people expect miracles from the POS mag-base antenna supplied with the generic dongle - you started with a decent antenna.

Essentially you’ve done everything right so far.
You nearest neighbor is doing quite well, so there is room for improvement.
With antenna location - height is king. Is there a possibility of getting it up above roofline?

1 Like

Two other filter option, even though I would go with @wiedehopf suggestion:

There is an earlier version, coloured in lighter blue, that is now sold as an 978&1090.

And this relatively new one:

Thank you all.
Will order the filter. When I get it and installed will report the results.