What do I do wrong/how can I debug my antenna?


#1

So, I just installed my first antenna/Pi/etc… and it worked fine. I can see it on the “claim” page and I can open up the web interface on port 8080. It does not show any messages, though. The antenna sits on my windowsill, facing a whole lot of sky. I can actually hear planes (I’d be able to see them, too, if it weren’t that cloudy) flying into ZRH and BSL, but the antenna doesn’t pick up anything.

Is there anything I can do to find a possible reason for that problem? Restarting the Pi and replugging the dongle and the antenna all didn’t do anything.


#2

Hi dominikschwind,
Please tell us more about your setup.
Which software are you using with your pi ,piaware image ?
Can you log into the pi from a keyboard and screen attached to it or via another computer by remote connection ?

I checked but it seems that the claim to your Flightaware station did not function.


#3

Hi Radiostationx , thanks. :slight_smile:

I followed the instructions here: piaware.flightcdn.com/piaware-je … -5.img.zip

I guess that the claim for the station only functions once it starts to relay messages? I can see my pi on flightaware.com/adsb/piaware/claim and after ssh-ing into my pi I can see that /tmp/piaware.out is telling me that it did find my account automatically:



04/09/2016 10:17:21 logged in to FlightAware as user dominikschwind
04/09/2016 10:17:50 0 msgs recv'd from dump1090; 0 msgs sent to FlightAware
04/09/2016 10:22:50 0 msgs recv'd from dump1090 (0 in last 5m); 0 msgs sent to FlightAware
04/09/2016 10:27:50 0 msgs recv'd from dump1090 (0 in last 5m); 0 msgs sent to FlightAware
04/09/2016 10:32:50 0 msgs recv'd from dump1090 (0 in last 5m); 0 msgs sent to FlightAware
04/09/2016 10:37:50 0 msgs recv'd from dump1090 (0 in last 5m); 0 msgs sent to FlightAware
04/09/2016 10:42:50 0 msgs recv'd from dump1090 (0 in last 5m); 0 msgs sent to FlightAware
04/09/2016 10:47:50 0 msgs recv'd from dump1090 (0 in last 5m); 0 msgs sent to FlightAware
04/09/2016 10:52:50 0 msgs recv'd from dump1090 (0 in last 5m); 0 msgs sent to FlightAware
04/09/2016 10:57:50 0 msgs recv'd from dump1090 (0 in last 5m); 0 msgs sent to FlightAware
04/09/2016 11:02:50 0 msgs recv'd from dump1090 (0 in last 5m); 0 msgs sent to FlightAware
04/09/2016 11:07:50 0 msgs recv'd from dump1090 (0 in last 5m); 0 msgs sent to FlightAware
04/09/2016 11:12:50 0 msgs recv'd from dump1090 (0 in last 5m); 0 msgs sent to FlightAware
04/09/2016 11:17:20 no new messages received in 3600 seconds, it might just be that there haven't been any aircraft nearby but I'm going to try to restart dump1090, just in case...
04/09/2016 11:17:20 attempting to restart fadump1090.sh using 'invoke-rc.d fadump1090.sh restart'...
04/09/2016 11:17:21 dump1090 restart appears to have been successful
04/09/2016 11:17:31 ADS-B data program 'dump1090' is listening on port 30005, so far so good
04/09/2016 11:17:31 Starting faup1090: /usr/lib/piaware/helpers/faup1090 --net-bo-ipaddr localhost --net-bo-port 30005 --stdout
04/09/2016 11:17:31 Started faup1090 (pid 1594) to connect to dump1090
04/09/2016 11:17:51 0 msgs recv'd from dump1090 (0 in last 5m); 0 msgs sent to FlightAware
04/09/2016 11:22:50 0 msgs recv'd from dump1090 (0 in last 5m); 0 msgs sent to FlightAware
04/09/2016 11:27:50 0 msgs recv'd from dump1090 (0 in last 5m); 0 msgs sent to FlightAware
04/09/2016 11:32:50 0 msgs recv'd from dump1090 (0 in last 5m); 0 msgs sent to FlightAware


Could it be a hardware problem? How could I check this?


#4

is the dongle attached ?
check with


lsusb

check dump1090 is running

look at processes running by inserting command


top

escape this screen via Q for quit

Check antenna connecting lead, especially sma connectors on a pigatil lead if you have one and make sure centre pin is present and fitting into socket of the dongle.


#5

Yepp, both look good:



pi@piaware:~ $ lsusb
Bus 001 Device 005: ID 1d19:1101 Dexatek Technology Ltd. DK DVB-T Dongle
Bus 001 Device 004: ID 7392:7811 Edimax Technology Co., Ltd EW-7811Un 802.11n Wireless Adapter [Realtek RTL8188CUS]
Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp. SMSC9512/9514 Fast Ethernet Adapter
Bus 001 Device 002: ID 0424:9514 Standard Microsystems Corp. 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
pi@piaware:~ $ top

top - 11:43:22 up  1:50,  3 users,  load average: 0.20, 0.19, 0.21
Tasks: 110 total,   1 running, 109 sleeping,   0 stopped,   0 zombie
%Cpu(s):  4.1 us,  0.8 sy,  0.0 ni, 95.0 id,  0.1 wa,  0.0 hi,  0.1 si,  0.0 st
KiB Mem:    948016 total,   269548 used,   678468 free,    74012 buffers
KiB Swap:        0 total,        0 used,        0 free.   111336 cached Mem

  PID USER      PR  NI    VIRT    RES    SHR S  %CPU %MEM     TIME+ COMMAND                                                                              
 1585 root      20   0   25480   6684   1708 S  16.8  0.7   4:55.41 dump1090                                                                             
 1649 pi        20   0    5108   2516   2164 R  11.2  0.3   0:00.06 top                                                                                  
    1 root      20   0    5476   3908   2740 S   0.0  0.4   0:05.24 systemd 


My antenna is just this little thing that came with the dongle: amazon.de/dp/B009HR8D38


#6

All seems ok there Dom,
You should be seeing at least some activity on your dump1090 screen using :8080
I suspect the antenna, the ones that come with dongle are not great performers but you can improve things a whole lot with some small changes (cut to correct size) and a tin can to optimise the dongle tv/radio antenna for adsb.
Take a look at first post by member abcd567 below

ads-b-flight-tracking-f21/three-easy-diy-antennas-for-beginners-t20177.html

what happens if you


sudo service piaware stop


./dump1090 --inteactive

anything happening in the terminal window ?


#7

A-ha!



pi@piaware:~ $ /usr/bin/dump1090 --interactive
Found 1 device(s):
0: Realtek, DVB-T Dongle, SN: 00000991 (currently selected)
usb_claim_interface error -6
Error opening the RTLSDR device: Device or resource busy



#8

did you stop piaware first ?
The dongle may be busy running piaware hence the message ! :wink:

If you stopped piaware before getting the message we may need to change something.


#9

Yeah, but somehow it didn’t stop the dump1090 that was running. I killed it manually, now I can start it - it isn’t showing anything, though - except for that header.
(Hex, Mode, Sqwk, etc.)


#10

Useful for debugging…

To see what FA related processes are up,
sudo piaware-status

Determine if dump1090 is outputting messages,
nc localhost 30003

Check port connections,
sudo netstat -tapu or sudo netstat -ntapu


#11

Okay, so, I didn’t have all that much time since the last time, but I did let my dingus running for a couple of days and it looks pretty much like it is the antenna’s problem. Apparently it does pick up some messages, but nothing enough to lock on a plane. I’ll experiment further when I have more time again. Thanks for the help, Radiostationx and crkbday!


#12

Ensure that you are using the correct connectors and that they are filly seated
The FA devices use SMA or N connectors.

There are similar connectors call SMA-RP for reverse polarity.
We did have one user with the incorrect cable. They would plug into each other but were effectively female to female.

F and SMA look similar but the threads are a different size.

There is an issue with the N connector for the FA antennas. The antennas have 50 ohm sockets. It has a larger opening when compared to the 75 Ohm version. If a 75 Ohm plug is used, the pin may not even touch the socket as it is much smaller than the 50 ohm version.


#13

@jonhawkes2030
I do not think that this is connectors issue - Dominik is using what came with his dongle.

@dominikschwind
Your dongle is not R820T based one (and I am not sure if it is supported by rtlsdr library), so you may need to find a correct driver to blacklist. Also, you may need to check what gains your dongle support and insure that the gain parameter is set correctly.


#14

The dongle is being found OK (note how dump1090 is running and taking CPU); it’s probably that the tuner chip on that dongle is no good at 1090MHz. You really want one with a R820T.

edit: according to sdr.osmocom.org/trac/wiki/rtl-sdr it might be a FC2580 tuner which does 146 - 308 MHz and 438 - 924 MHz; no good at 1090MHz.


#15

So, I tried a different receiver and suddenly things are a lot better. :slight_smile: I still don’t see much - I’m in a valley, so I didn’t have huge expectations, but now the antenna sees what I see, which is lovely. Thanks everybody, you’re outstanding people.