How do I setup MLAT for my node?
How is your node implemented?
If it’s just dump1090-fa and piaware on a Raspberry Pi, you don’t have to do anything extra to get MLAT to run.
Yeah it’s dump1090-fa on a pi. But does the MLAT go to green at some point?
Yes it should. It usually takes a few minutes.
If it doesn’t go green after about 10 minutes, you could check piaware log:
sudo journalctl -u piaware -f
That will show the latest on the piaware log.
End it by doing a control c.
It shows raspberrypi piaware[74646]: mlat-client(74660): Server status: clock unstable
Aircraft: 16 of 22 Mode S, 40 of 45 ADS-B used
No issues that I could tell from the dump1090-fa log:
adaptive: available dynamic range (34.7dB) >= required dynamic range (30.0dB), stopping downwards scan here
Looks like a problematic USB connection to the SDR dongle.
How is the SDR dongle connected to the Rpi ?
It connects directly to the usb slot using the flight aware pro
It’s using the pro stick + with the bandwidth dual filter
The clock is fine.
Ref time (UTC) : Wed Apr 29 22:19:24 2026
System time : 0.000000015 seconds fast of NTP time
Last offset : -0.000155378 seconds
RMS offset : 0.000155378 seconds
Frequency : 2.732 ppm fast
Residual freq : -67.602 ppm
Skew : 1000000.000 ppm
Root delay : 0.028727839 seconds
Root dispersion : 33.595870972 seconds
Update interval : 2.0 seconds
Leap status : Normal
The Nooelec dual LNA/filter? That shouldn’t matter.
Other people have reported problems when the dongle is plugged directly into the Rpi USB port. You might try a USB extension cable if you have one.
Did MLAT just recently stop working?
No the MLAT has always been at best yellow. Never seen it green.
Just saw this in the log:
mlat-client(511189): Beast-format results connection with ::1:30104: connection established
That’s good to know the issue comes from the usb connection. I thought I had to install additional stuff.
Ref time (UTC) : Wed Apr 29 22:19:24 2026
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What clock is that? Do you have a GPS receiver?
NOt sure what clock that is. It’s just UTC time. No GPS receiver.
Ok – it doesn’t matter. You don’t need a time-of-day clock for MLAT.
Usually MLAT problems are due to USB connection.
I have seen the dump1090 goes offline fairly often. So maybe the issue was the connection to the pi.
