Oh.
As Cnada does not have UAT, I thought I picked planes across Canada-USA border which is close to Toronto.
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For real data, youāll see multiple messages with the same address, and an address qualifier of 0, and aircraft state that isnāt obviously junk.
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Thanks, for the tips. I will now be able to scrutinize the data before rejoicing 
I think all this junk & noise is caused by too much amplification and strong cell phone signals. The uat-sdr-gain is currently at default 49 with ProStick orange + FA light-blue filter, no filter. Antenna is indoors, 76mm mag-mount on cookie can
I have now reduced gain of 978 dongle to 42. Lets see if it helps reducing garbage signals.
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Not much UAT 978 MHz traffic so far. Over a few days capturing the output of the JSON port, there are 272 JSON records. Of those, 209 have address_qualifier:3 and 36 has address_qualifier:2. The records with other address_qualifier values appear to be garbage. As far as I can tell by browsing dump978 source code, 2 and 3 are both associated with TIS-B. So I have yet to receive anything from an aircraft. Is that a fair interpretation?
address_qualifier count
----------------- -----
0 2
1 1
2 36
3 209
4 7
5 4
6 8
7 6
I am seeing a modest number of UAT transmissions. The ground station at BWI is active, and on a nice VFR day there are numerous light aircraft. I also see some aircraft which are transmitting both Mode S and UAT.
A typical collection of airliners on the ground at BWI:
Lacking a way to inject a test signal I ātunedā the system gain by turning down the value in the piaware-config file to the point where the ground station RSSI is about -10 dBFS.
Basically the same I have right now except I had made a cantenna cut at 3 inches.
Iāve made a couple of changes for the next version which should help here:
- overflow errors are no longer fatal, instead they get counted & reported every ~15 seconds
- I made some performance improvements to the CS16 conversion code
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Before the change the two cpu-heavy threads had loads of 83% and 34% using the aisrspy soadpysdr driver.
After the change this has reduced to 44% and 34% so may well run on the hardware jon is running.
(tested on Intel(R) Coreā¢ i5-3320M CPU @ 2.60GHz)
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I just tried to add 978 to my Raspberry Pi rig this morning, and am also plagued by the looping OVERFLOW failures on 978 (1090 is working fine).
What would I do to implement the changes (fixes?) you made? I started with a fresh 3.7.0.1 image from the link at the top of the thread, and also corrected the location bug.
Thanks!
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You would have to clone the dump978 git repository, use git checkout dev to switch to the development branch and then compile and install it.
Which RPi are you working with, it might just not be fast enough for handling dump978 and dump1090-fa at the same time.
Station #5252 Antennas
- Left mag-mount with steel binding wire cut to 76mm (for 978 Mhz)
- Right mag-mount with original whip, cut to 67mm (for 1090 Mhz)
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Itās a Pi B+ v1.2 (2014)
Are the default ssh credentials for this 3.7.0.1 image pi/raspberry? Iām not having any luck logging in via ssh:
ssh pi@172.16.10.95
pi@172.16.10.95ās password:
Permission denied, please try again.
The default username / password are
pi / flightaware
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I wouldnāt try to run 1090 and UAT/978 at the same time on that hardware.
It is insufficient.
Excellent, thanks. Perhaps @abcd567 would consider adding that to the quick-start guide?
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For Beginners - How-to SSH to RPi - Setup Putty in Windows
Did you create the ssh file on the boot partition?
Edit: i guess he would add it there if he could still edit that guide.
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Yesā¦ I had no problem connecting, just didnāt know what the credentials were.