Not receiving any 978 signals on ADSBExchange Orange dongle

Technical Support
1

20240709_112458
20240709_1124584000×3000 492 KB

Running adsbx-8.2.220910 on rPI4 and am picking up 1090 all day long, but not a single 978. Even if I run the Orange dongle by itself. There are 4 muni airports within a 10 mile radius. The dump978 log shows nothing. I’ve tried an RTL-SDR and a Nooelec as well but still no results.
config:
/boot/adsbx-978env

  • RECEIVER_978_OPTIONS=“–net-only”

  • DECODER_978_OPTIONS=“–max-range 460”

  • NET_978_OPTIONS=“–net --net-heartbeat 60 --net-ro-interval 0.5 --net-ro-port 0 --net-sbs-port 0 --net-bi-port 0 --net-bo-port 0 --net-connector localhost,30004,beast_out”

  • JSON_978_OPTIONS=“–json-location-accuracy 2”

  • ENABLED=yes

  • #RECEIVER_OPTIONS=“–sdr-gain 36.4 --sdr driver=rtlsdr,serial=978 --format CS8”

  • RECEIVER_OPTIONS=“–sdr-gain 36.4 --sdr driver=rtlsdr,serial=978 --format CS8”

  • DECODER_OPTIONS=“”

  • NET_OPTIONS=“–raw-port 30978 --json-port 30979”

log after a fresh boot:
– Journal begins at Mon 2024-07-08 23:44:58 MST, ends at Mon 2024-07-08 23:45:50 MST. –
Jul 08 23:45:03 adsbexchange systemd[1]: Started dump978 ADS-B UAT receiver.
Jul 08 23:45:04 adsbexchange dump978-fa[499]: raw-port: listening for connections on 0.0.0.0:30978
Jul 08 23:45:04 adsbexchange dump978-fa[499]: raw-port: listening for connections on [::]:30978
Jul 08 23:45:04 adsbexchange dump978-fa[499]: json-port: listening for connections on 0.0.0.0:30979
Jul 08 23:45:04 adsbexchange dump978-fa[499]: json-port: listening for connections on [::]:30979
Jul 08 23:45:05 adsbexchange dump978-fa[499]: Found Rafael Micro R820T tuner
Jul 08 23:45:05 adsbexchange dump978-fa[499]: usb_claim_interface error -6
Jul 08 23:45:06 adsbexchange dump978-fa[499]: Found Rafael Micro R820T tuner
Jul 08 23:45:06 adsbexchange dump978-fa[499]: Exact sample rate is: 2083333.135571 Hz
Jul 08 23:45:06 adsbexchange dump978-fa[499]: [R82XX] PLL not locked!
Jul 08 23:45:06 adsbexchange dump978-fa[499]: SoapySDR: using manual gain 36.4 dB
Jul 08 23:45:06 adsbexchange dump978-fa[499]: SoapySDR: using stream setting buffsize=262144
Jul 08 23:45:06 adsbexchange dump978-fa[499]: Allocating 15 zero-copy buffers
Jul 08 23:45:06 adsbexchange dump978-fa[499]: 0.0.0.0:30978: accepted a connection from 127.0.0.1:5505

any help is appreciated.

2

My guess is dump978 is trying to use a device that is already in use. Check your dump1090 and dump978 configs to make sure that the proper dongle is assigned to each. You can use rtl_test to view the RTL-SDR devices currently connected to your device.

sudo apt install rtl-sdr
rtl_test

You should see something like this.

Found 1 device(s):
  0:  Realtek, RTL2838UFA, SN: 00000628
  1:  Realtek, RTL2838UFA, SN: 00000972

I would also make sure unwanted kernel modules are not being loaded by creating the following file if it does not already exist.

/etc/modprobe.d/rtlsdr-blacklist.conf

Then make sure the file contents the following lines.

blacklist dvb_usb_v2
blacklist dvb_usb_rtl28xxu
blacklist dvb_usb_rtl2830u
blacklist dvb_usb_rtl2832u
blacklist rtl_2830
blacklist rtl_2832
blacklist r820t
blacklist rtl2830
blacklist rtl2832
3

altered /etc/modprobe.d/rtlsdr-blacklist.conf as proscribed.
booting clean with only the orange dongle: rtl_test
Found 1 device(s):
0: Realtek, RTL2832U, SN: 978

Using device 0: Generic RTL2832U
usb_claim_interface error -6
Failed to open rtlsdr device #0.

could it be that the dump1090 is grabbing the port causing the usb_claim_interface error -6? I disabled dump1090 in the UI. but still get the same error.

4

978 2024-07-11 161449
978 2024-07-11 161449822×123 6.24 KB

Reflashed the SD Card
added the entries to /etc/modprobe.d/rtlsdr-blacklist.conf and /etc/modprobe.d/blacklist-rtlsdr.conf (which already existed).
went to the ADSBEXCHANGE.LOCAL and set the software up for 978 ONLY
rebooted with JUST the 978 dongle on rPI4.
The image above is from the 978 MAP, after the reflash.

pi@adsbexchange:~ $ rtl_test
Found 1 device(s):
0: Realtek, RTL2832U, SN: 978

Using device 0: Generic RTL2832U
usb_claim_interface error -6
Failed to open rtlsdr device #0.
if the 1090 software isn’t installed what is taking the device?

5

In case anyone’s reading this later… there should not be any need to mess with blacklisting modules if using the ADSBx Pi image, and rtl_test will not be able to open the SDR if dump978-fa aleady has it open.

6

The execution of rtl_test was recommended to identify the connected devices in order to ensure they were assigned properly in the dump1090 and dump978 configurations. If the devices are not specified in each configuration, then one might very well encounter an issue where both dump1090 and dump978 decide the same device belongs to them.

From the dump1090 configuration file.

# serial number or device index of device to use (only needed if there is more than one SDR connected)
RECEIVER_SERIAL=

And for dump978 the following option when executing the application.

--sdr specifies the SDR to use, in the format expected by SoapySDR. For a rtlsdr, try --sdr driver=rtlsdr. To select a particular rtlsdr dongle by serial number, try `–sdr driver=rtlsdr,serial=01234567

I know back in the day when I first started the ADS-B Receiver Project on GitHub there was no “if it fails move to the next” logic. I am guessing that this is still the case being these settings are still available in both dump1090 and dump978 but I may be wrong.