I have had my ADS-B receiver running all day. I have green boxes in PiAware and FlightAware.
Hourly received reports are " no reports received" . No aircraft detected. I live in quite a remote area and there aren’t that many planes.
Question: Are no reports received because there are no aircraft detected or because the Rasp Pi board is not receiving reports from the DVBT dongle ?
tnx
Mike
I checked your stats page to get your approximate location. I’d say that yes, you are in a remote area, but not so remote that you would get no aircraft.
Could you tell us more about your setup? Specific equipment, where your antenna is located, etc.?
mooksmd seems to be located in a valley at approximately 3500’ elevation that is surrounded by 4500’ and 5000’ terrain. I’ve been in that area and an aircraft sighting is quite rare. The closest major airport is YVR 185 miles south on the western side of the coastal mountain range.
Thanks for the reply.
Equipment.
DVB-T +DAB+FM dongle.
Rasp Pi 4
Mag mount vert antenna
3A power supply.
About 5- 10 aircraft/day come within 200km of my location.
Antenna is mounted behind a picture glass window facing due south. We are on a high spot
overlooking the valley , absolutely no obstructions in view.
tnx for the help.
Mike
One possible factor learned the hard way. I had an antenna behind a window, and the window was a low-emissivity glass with thin metallic film coatings to reduce heat loss. Sadly, it also acts like a radio signal shield. Very similar to the metal clad insulation used when building energy efficient houses. I moved the antenna into the attic.
One way to test if this is your situation, place the antenna outside and away a bit from the window. If your reception improves, you may have an Low-E window saving you on heating bills. Moving the antenna around in the house to find better reception may help also. I hope you can find a good location. Maybe an upper window or in the attic (assuming you do not have a metal roof). Good luck, and have fun making your improvements to your system.
Gene
That’s not precise enough, some have the wrong tuner.
Gotta specify the exact product you got … and possibly double check in the receiver logs or stop dump1090 and run rtl_test.
1090 MHz is line of sight, so you might have less than 200 km range for aircraft at 40000 ft if the ridge of the valley is higher than your position.
Make yourself a heywahtsthat panorama to get an idea of what’s possible: GitHub - wiedehopf/tar1090: Provides an improved webinterface for use with ADS-B decoders readsb / dump1090-fa
Thanks for the reply. I am new to ADS-B and dongles. I can manage in Linux.
- How do I determine the exact product? All that is written on it is “DVB-T+DAB+FM”
- How do I stop dump1090?
- I have run rtl_test before and I always get an error but I didn’t know that I had to stop dump1090 first.
- Most of the aircraft are south of my location. The valley runs north-south and so view of the sky to the south is very clear.
- I have also tried a Nooelec NESDR but no luck with it either.
tnx for help. - Here is a snippet of the last lines from the log.
msgs sent to FlightAware
[2024-02-26 17:21 UTC] no new messages received in 3727 seconds, it might just be that there haven’t been any aircraft nearby but I’m going to try to restart everything, just in case…
[2024-02-26 17:21 UTC] faup1090 exited with SIG SIGHUP
[2024-02-26 17:21 UTC] dump1090 restart appears to have been successful
[2024-02-26 17:21 UTC] ADS-B data program ‘dump1090-fa’ is listening on port 30005, so far so good
[2024-02-26 17:21 UTC] Started faup1090 (pid 14312) to connect to dump1090-fa
[2024-02-26 17:21 UTC] Starting faup1090: /usr/lib/piaware/helpers/faup1090 --net-bo-ipaddr localhost --net-bo-port 30005 --stdout --lat 51.751 --lon -124.470
[2024-02-26 17:21 UTC] 0 msgs recv’d from dump1090-fa (0 in last 5m); 0 msgs sent to FlightAware
[2024-02-26 17:26 UTC] 0 msgs recv’d from dump1090-fa (0 in last 5m); 0 msgs sent to FlightAware
[2024-02-26 17:31 UTC] 0 msgs recv’d from dump1090-fa (0 in last 5m); 0 msgs sent to FlightAware
Mike
I’m assuming that your “magnetic base antenna” is a whip antenna with +3Db gain. You might want to look into getting an antenna with better gain characteristics. There are a number of +6Db gain antennas designed for ADS-B reception available on Amazon and other retailers.
Also, if you’re certain all or most aircraft are to the South of you, you may consider putting a reflector behind it.
sudo journalctl -u dump1090-fa -n100
To show logs for dump1090-fa.
If you’re linux familiar you already know now
sudo systemctl stop dump1090-fa
to stop it, then use start to start it again.
With that one you at least know it’s a tuner that’s suitable for 1090 MHz.
Possibly your antenna is just terrible or the glass is actually coated.
To be honest 200 km needs some decent hardware at least and some whatever antenna and an SDR that doesn’t have the LNA / filter on it is not trivial.
I have some resources linked here: Raspbian Lite: ADS B receiver · wiedehopf/adsb-wiki Wiki · GitHub
graphs1090 will be useful to at least show the noise level and things like this.
There can be issues with interference from HDMI cables.
The coax to the antenna can be terrible.
Thanks for the help.
I am trying to determine whether it is an antenna problem or receiver problem.
I don’t want to invest a lot in new antennas if the problem is the receiver.
When I was trying to get the Nooelec NESDR running, I was in contact with Nooelec and
they kept saying that it needed drivers before it work. I was never able to get the drivers properly installed
so I gave up on the Nooelec.
I will try stopping the dump1090-fa and see what happens.
tnx
Mike
Are you using a Flightaware image operating system (OS) preconfigured with piaware and dump1090-fa? Perhaps a Raspberry OS with separately installed piaware and dump1090-fa. Just asking to rule out other OS’s that may influence what your system is doing. Sounds like some configuration issue. The Mag mount cables can be a problem also as wiedehopf points out above.
It’s just an rtl-sdr … which is what you’re running now.
Stopping dump1090-fa is only for rtl_test to check the tuner, restart it after.
Without dump1090-fa (the decoder talking to the SDR) you can’t receive any aircraft 
You can always take a photo of your SDRs and post it here, same for the antenna.
@wiedehopf brings up a good point: What kind of coax are you using? Is it just the cable that the whip antenna has attached? At that length it shouldn’t be an issue, but if you’ve got additional cable then knowing what you’re using and how long it is could help figure out if the cable itself is an issue.
The cable is a pigtail (sma to mcx )about 10cm long , so it shouldn’t be an issue.
tnx for the help. For some reason when I try and SSH into the Pi now it won’t accept
the password ( yes, I wrote it down)… Once I sort that out, I will try the stop dump1090.
Mike
Thanks for the reply… I down loaded the FlightAware image operating system.
tnx
Mike
I reloaded the image file and can now SSH again .
Tbis is what I get when I tried to run the stop dump1090.
"sudo systemctl stop dump1090-fa-n100
Failed to stop dump1090-fa-n100.service: Unit dump1090-fa-n100.service not loaded."
Right after that I ran “rtl_test” and this is what happened.
"pi@piaware:~ $ rtl_test
Found 1 device(s):
0: Realtek, RTL2838UHIDIR, SN: 00000001
Using device 0: Generic RTL2832U OEM
usb_claim_interface error -6
Failed to open rtlsdr device #0."
Advice about where to go from here would be much appreciated.
tnx for the help.
Mike
I don’t think the service is called sudo systemctl stop dump1090-fa-n100
the correct command is listed below
sudo systemctl stop dump1090-fa
Then run the rtl _test again and post the results
1 Like
thanks , here is the result of running rtl_test after stopping dump1090:
"Found 1 device(s):
0: Realtek, RTL2838UHIDIR, SN: 00000001
Using device 0: Generic RTL2832U OEM
Found Fitipower FC0012 tuner
Supported gain values (5): -9.9 -4.0 7.1 17.9 19.2
Sampling at 2048000 S/s.
Info: This tool will continuously read from the device, and report if
samples get lost. If you observe no further output, everything is fine.
Reading samples in async mode…
Allocating 15 zero-copy buffers
lost at least 124 bytes"
There has been no further output.
tnx for the help.
Mike
That device is not suited for the reception of ADS-B signals, the Fitipower FC0012 tuner is the issue why you don’t receive anything.
So hardware is preventing it.
I replace the DVTB tuner with the Nooelec NESDR and then ran the same commands… here is the output.
"pi@piaware:~ $ rtl_test
Found 1 device(s):
0: Nooelec, NESDR SMArt v5, SN: 00000001
Using device 0: Generic RTL2832U OEM
Found Rafael Micro R820T tuner
Supported gain values (29): 0.0 0.9 1.4 2.7 3.7 7.7 8.7 12.5 14.4 15.7 16.6 19.7 20.7 22.9 25.4 28.0 29.7 32.8 33.8 36.4 37.2 38.6 40.2 42.1 43.4 43.9 44.5 48.0 49.6
[R82XX] PLL not locked!
Sampling at 2048000 S/s.
Info: This tool will continuously read from the device, and report if
samples get lost. If you observe no further output, everything is fine.
Reading samples in async mode…
Allocating 15 zero-copy buffers
lost at least 88 bytes"
seems a bit strange that the PLL is not locked.
tnx for the help.
Mike