Enhancements to Dump978 (UAT decoder)

I’ve made a couple of minor enhancements to the dump978 source for those utilizing it.

Two improvements have been made.

  1. RSSI measurements have been added. uat2text, uat2json, and uat2esnt all now provide rssi measurements.
  • uat2text provides rssi on a line at the end of each message.
  • uat2json provides rssi information for each aircraft.
  • uat2esnt provides rssi with each ADSB ES message that is sent.

A few notes on this. uat2json provides the most recent UAT message’s RSSI. So it is more of an instantaneous rssi and not averaged over time. This means that if you are using uat2json and uat2esnt and looking at both maps at the same time they will not have the exact same RSSI. This is because dump1090 averages rssi over the last 8 ADS-B messages. Each UAT message is ~3 or 4 ADS-B messages. So dump1090 is really showing the average of the last 2 or 3 UAT messages.
The changes to uat2esnt have been tested with dump1090 and nothing else. Sending RSSI involves also sending the timestamp which I have not filled out appropriately. dump1090 ignores this field anyway so it doesn’t matter for it.

  1. Receiver position can now be set in uat2json (e.g. uat2json --rec-pos 12.56732,32.72354 /var/run/dump978)
    This allows for both range rings and distance measurements for aircraft to be populated on the map.

If anyone is interested I would love to hear back if it works for them as well as it seems to be working for me.
Source located here: GitHub - KeyserSoze1/dump978: Experimental demodulator/decoder for UAT on 978MHz


How can I just update this, without re-installing from the script?
“sudo apt-get install --only-upgrade dump978” says “Unable to locate package dump978”

LE: I will update using the script from here:

There probably isn’t a way to update the ADS-B receiver project install automatically without modifying the install script and re-installing.

Line 147 of the dump978.sh would need to be updated to have “git clone GitHub - KeyserSoze1/dump978: Experimental demodulator/decoder for UAT on 978MHz

My understanding, and the way it appeared to have worked for me, is to run the script and only answer yes to the portions that you want to update. Currently I only use the graphs, so I answered no to everything, except for the Portal installation.

It this a fork? I can try to change it, but lately the number of planes with UAT dwindled here…

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Thanks for doing that! I’ll be upgrading shortly… I see Oliver hasn’t replied to your pull request. He used to be so active on this stuff. I wonder if he is still with FA…

I have updated modifying the line 147 of the dump978.sh and reinstalling.
I see, at times, a few “Messages/sec”, but not actual plane positions on the map. In between the messages drop to zero. Can it be that those planes don’t have GPS positioning (and there is no MLAT for them either)? Or is something else wrong? How can I tell if indeed I am using indeed the new code?
Sometimes I even hear the plane above (and it is not shown either on the dump1090).


I have changed back that line to mutability branch, reinstalled (it deleted the whole folder and recompiled the dump978).
Now I can see planes.

Maybe it was just a coincidence? Dunno

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Interesting. I have no idea why you wouldn’t be able to see planes on the map. You aren’t using the new receiver position inputs into uat2json but that shouldn’t affect seeing planes.

@N456TS have you had a chance to try this and are you having any issues?

Maybe there is something else that I need to change besides that line?
Or it was just a coincidence…

In order to see range rings on the map and distance measurements to the aircraft you need to change line 292 also.

tee >(${RECEIVER_BUILD_DIRECTORY}/dump978/dump978/uat2json --rec-pos lat,lon ${LIGHTTPD_DOCUMENT_ROOT_DIRECTORY}/dump978/data)

The --rec-pos lat,lon needs to be added with your location information.

This really shouldn’t affect you seeing airplanes though.

I’ll try again. Unfortunately, the number of UAT planes seems to go down, I see more and more private small planes use 1090 MHz ADS-B.

LE: I did add the coordinates and I still don’t see the circles and the dot.

Make sure when you specify the coordinates that there is no space between lat and lon. Just a single comma.

It’s not. But it is a “-” from the longitude. And each position has 5 decimals.


  1. Open file config.js for editing

    sudo nano /var/www/html/dump978/config.js

  2. In the file opened, scroll down to starting with SiteShow = false;
    change false to true

    // Center marker. If dump1090 provides a receiver location,
    // that location is used and these settings are ignored.

    SiteShow    = false;           // true to show a center marker
    SiteLat     = "43.xxxx"
    SiteLon     = "-79.xxxx"
    SiteName    = "My Radar Site"; // tooltip of the marker

  1. Save file (Ctrl+o) and close (Ctrl+x)
  2. Clear browser cache (Ctrl+Shift+Delete) and Reload (Ctrl+F5)

Before editing config.js

After editing config.js

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That was it, thanks!
I remember seeing mentioned it somewhere by you, but I didn’t remember where (“bake a pi” maybe?), this new format is horrible.
And I didn’t need to refresh anything, the markers just appeared after save.

Still, all the UAT planes are to sleep now, I’ll check tomorrow again.

Thanks for the info. I did not know about that one. My change writes the position to the receiver.json file. Did the ADS-B receiver project change how that works for the 978 map? I’m using the standard dump1090-mutability map for 978.

I don’t see why the RSSI changes would cause the planes not to show. A “0” value was written there before. I just updated it so that measured value is populated in the aircraft.json file.

I have updated again my install. Will wait and see… right now there are 0.0 mess/sec.

I am not sure how JP does it, but found that dump978 map files did not exist when I installed ONLY dump978, and nothing else using JP’s script.

Only when I installed Web Portal and in ip-of-pi/admin/index.php >> Navigation tab placed checkmark besides Enable live dump978 map link, the folder /var/www/html/dump978 alongwith its all map files appeared.

The above noted folder dump978 has the same files as are in folder /usr/share/dump1090-mutability/html in a mutability install, or in public_html folder of mutability’s cloned files from github.


I forgot to tell that I installed (dump978 + webportal) on Piaware SD card image.

As I already had dump1090-fa and Piaware data feeder, I installed dump978 only, but found that dump978 map files were missing from folder /var/www/html/dump978.

When I installed Web Portal, only then the map files appeared inside the folder /var/www/html/dump978.

I am not sure if this is due to some bug, or is intentional.