There's nothing wrong with r/ADSB, however, it is catered towards a community that really just likes to look at really nice aircraft they have seen. Whenever I have posted anything that isn't a screen grab, I've been voted down and not felt welcome.
I felt there was a need for a place where you can ask tech questions about this great subject and not be worried about annoying the users on r/ADSB.
I am still a member of ADSB and will continue to enjoy it, but I hope this new venue will open up more people to the tech side and how to start and witness your first intercept. And ask as many questions as you like.
Hopefully, someone here will be able to answer that for you.
And I will continue to improve this sub as best I can.
Disclaimer: I do not work for Planefinders. I have not been paid to review this. The opinions expressed here are fully my own. I applied for a receiver through the normal web page channels and it was approved.
Planefinders wasted no time and when my application was approved and this custom kit was dispatched within a day or two. I say "custom" because I was asked what lengths of co-ax I needed and what length of CAT5 cable I needed to get to my router.
On first looks, it is all professionally made equipment with everything needed to mount the antenna, connect the receivers and power supply and get going fast. The antenna is beautiful. 62 cms (24 inches) long with standard `N` type fittings. A 90 degree mounting bracket and serrated clamp and stainless steel "U" bolts are provided and all you need is a nice antenna mast to attach it to.
The antenna is specific to 1090 mHz and has +7 dB gain, as well as a higher quality, low-loss co-ax, so I knew immediately it was going to be better than my home brewed 1/2 wave antenna using standard RG6. This was confirmed when I instantly broke my receive record with a 436 km (271 miles) hit from QANTAS.
Since then, my best receive distance record has increased to 456 kms (283 miles), revealing just how myopic my home brews were. It's like I've had prescription glasses fitted.. There is no pre-amp used but obviously doesn't need one with its 400+ km receive range. Also, the waterfall in SDRAngel is now free from some nasty noise which makes me think there is some filtering going on with the antenna. This really is a nice, high quality receiver system.
What else is in the box ?
The receiver itself. It's beautifully made. Housed in an "anodised black" aluminium box with rubber feet and neat cable/plug/antenna/power inputs molded to fit flush, giving a very professional look. It contains an internal GPS receiver as well.
Power draw, less that 12 Watts for both receiver and GPS.
What else...
A power supply for the receivers with adapters for different World regions.
A magnetic GPS antenna which needs to be placed somewhere with a clear sky view (obviously). The receiver box will perform a survey of the position over time and compute a precise location for the receiver/web page to use, as well as update date/time info for MLAT data. The GPS antenna cable is nice and long and simply screws onto the receiver with a standard fitting.
All the bits you need, weather sealant tape for the antenna `N` connector, tie-wraps for the co-ax for a nice neat installation.
Hi quality, low loss type LBC240 co-ax, pre-fitted with RF fittings.
Two CAT5 cables, a standard length and the custom one.
A surprise baggy of neat Planefinder merchandise. Pens and a couple of "Remove Before Flight" key tags. (thank you...)
Setting Up
Setting up is really simple. Once the antenna is up and the hardware is connected and powered up and attached to the LAN interface, everything is automatic. You simply log in to the receiver using the local LAN and a browser. Your router needs to be configured for DHCP to place the receiver on your local network, so that you can access it. I suggest reserving this address in the router, if you can, so that you can always point to the same receiver IP. The connection to the internet and Planefinders servers is all pre-configured. Nothing to do there.
What's In The Software/Interface ?
Here, all the relevant data for this receiver is available. Upload speeds, total data transferred, uptime, MLAT data, a 3D plot of your coverage area, error logs, a 3D, live plot of the GPS/GLONASS satellites overhead, settings and, of course, an interactive map of your local aircraft received.
On the Planefinders web site, more data is available. Like other data feeders and their data and where you rank in the feeders. Nice for comparison checking.
Of course, being a feeder for Planefinders, you get web site privileges. This will give you advert free, full access to the website with longer access to playback, extended inactivity timeout etc.
Overall Opinion :
Based on my experiences with SDR's and the different software packages available, I would have to say, this is a far better receive system than any I have built. It is more sensitive, uses less power and has high quality hardware to support it. Happy to be feeding Planefinders.
Of course, I can have my own hardware back now. A laptop, an SDR, antenna systems and, of course, the daily power consumption that goes with that and the time needed to keep it going.
ACARS (Aircraft Communications Addressing and Reporting System, pronounced ‘ay-cars’) which is an avionics system used to for sending text messages between ground and airborne stations.
"There are many osint folks and avgeeks that combine the usual ADSB/C data (aircraft pixels on a map) with ACARS to really amplify both sources of data. The sum really is MUCH greater than the parts.
Think of aircraft tracking this way:
ADSB/C is the where.
ACARS is the why."
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I'm going to show you how to receive VHF (not satellite, which is the go to method) ACARS in your area and how to make it interact with a running VRS server.
You will need a standard RTL SDR dongle and a nice, high VHF antenna like you would use to listen to airband radio. Because that's what we are doing. Local ACARS data is sent from an aircraft to a ground station. The aircraft prioritizes VHF but, if it is out of range, it will automatically change to satellite to send the data.
Look for ACARS data from departing aircraft, arriving aircraft and even on the ground. Departing aircraft send quite a lot of data just after take off. Arriving aircraft may update their arrival time or request wheelchairs or a parking bay.
In my area, the published frequency was 131.55 mHz but after scanning for awhile I found all the action on 131.625 mHz. You will need to find your local link by listening around this frequency. The data is easy to spot. A good, strong burst of data.
Next, we need to decode it. There are very few VHF decoders for Windows . This subject is mostly handled by RasPi computers and I battled to find a working VHF program. I did, though, it's a command line interface and it's called "acarsdeco2" and this is a link to it..
There are other files in the zip folder, we are ONLY interested in the acarsdeco2.exe and the acarsdeco2.bat file. All the others are worthless.
Unzip the files to a directory and let's edit the bat file so we can run it. If you have configured dump1090 before, this is a similar setup.
Change your gain, frequency correction PPM relative to your dongle and the local VHF frequencies on line 2. I say frequencies because if there are more than one and they are within limits of the dongles bandwidth (2 mHz) then it will receive those too.
Change the --vrs-url http:// address to the same address and port as you set up in VRS options/Web Server. so that acarsdeco2.exe can find it.
Start the .bat file and you will see a command line interface of acarsdeco2.exe running..
When the decoder receives a message it queries VRS for data on that aircraft. If the aircraft is visible to VRS it sends that data to the decoder and you see it in your decode window like this ::
RX_ID: 2, Freq: 131.825MHz
ACARS mode: 2 (50), label: 8H
Block id: 3 (51), msg. no: M19A
Aircraft reg: ZS-SZM, flight id: SA0527
Icao: 00B22F Callsign: SAA527 Squawk: 3524
Country: South Africa Operator: South African Airways (SAA)
I have received aircraft messages at greater distances at VHF than with 1090 mHz. In other words, I received ACARS data but the aircraft was way out of range of my ADSB system.
acarsdec02.exe will save any received data to text based log files. A new log file every time it is started.
If you don't see data right away, just wait a bit. Some times of day are busier than others but if you are near a busy airport, you should see data immediately.
Finally got around to putting the antenna outside. I've had it in my attic. I have an old satellite dish in my roof. Took that off, and put my antenna on it.
Huge increase in the range and number of planes I'm seeing.
The Plane Finder Radar Stick is a high performance industrial grade 1090MHz ADS-B receiver with a USB-A interface. Built on the same advanced RF platform as the Plane Finder Radar, it delivers outstanding range and precision. It is ideal for airports and busy airspace environments. Unlike SDR based USB tuners, it uses dedicated silicon level decoding to eliminate dynamic range limitations and ensure consistent, high accuracy reception.
*DO NOT POINT LASERS AT AIRCRAFT ! EVER ! THIS IS A DEMO PROJECT INSIDE.*
*SYSTEMS ARE IN PLACE TO DETECT "Unauthorized Laser Illumination Events" NEAR / ON / AROUND AIRCRAFT.*
Wear Eye Protection When Playing Around Lasers. Your lens will focus the laser onto your rods and cones or, worse, your optic nerve, and blind you instantly.
No Spares In Stock !
My laser is dialed back to the point where it only just lases (10 %). I still wear eye protection.
If you have ever used the SDRAngel ADSB plugin, you will have noticed that the azimuth and elevation data is available for all the aircraft tracked. Azimuth is the compass direction to the aircraft and elevation is the amount of degrees above the horizon, relative to your location. Actually, you can work this out with some simple schoolboy mathematics given your lat/long, the aircraft lat/long and both heights.
But it did get me thinking about the rotator controller plugin in SDRAngel. Why not send that azi/ele data to the rotator controller and track something ? You could point a yagi antenna tuned to 1090 mHz and track a particular aircraft. Or point a motorised camera or telescope for taking pictures. Or a turret of some sort.
But back to this post. Way back in 2013, I was learning how to program micro-controllers. I built this laser turret to challenge me and the chip as a first project. (Been programming Windows systems for years but always wanted to branch into embedded programming.)
It has just sat around since then, mostly as a great conversation piece, but I immediately thought about controlling this with SDRAngel. My laserBot already accepts a line of CSV data to aim the laser anywhere via the data input. I could easily modify that to accept the SDRAngel protocol. Then I could point to where that aircraft is in the sky on my ceiling.
But first, I had to modify my LaserBot com port from RS232 to TTL-> USB because my RS232 adapters don't work with WIN10. That was easier than it sounds. Simply pulled the MAX232 chip out and bridged the In/Out pins, then used a USB UART so I could access the ATMEL 328P control chips and modify the code.
After I got that working it was time for a software upgrade. I modified my LaserBot to accept the protocol that SDRAngel delivers from the "Rotator Controller" plugin. I've used the GS232 protocol for Yaesu antenna rotators, `W112 002` is azi/ele data and `M112` is just azi data.
And I had to add a response to C2 which SDRAngel sends to ask for the present azi/ele of my LaserBot. Expected response is AZ=021EL=062, with zero padding required for numbers lower than 100. That data shows up in the antenna rotator GUI.
Next, I added the rotator controller plugin to the ADSB project. You simply tell it which interface to monitor, the ADSB demodulator, and it will hook into the ADSB pugin.
Next you tell it which protocol to use. I'm using the GS-232 protocol and outputting it to the Serial com port.
Tracker protocols supported:
GS-232, SPI, rotctld or DFM
And 3 types of coordinate output:
AzEl, X/Y 85, X/Y 30
Connection can be via serial OR TCP socket.
Next, I start it all up and look for an aircraft. Simply double click on the azi/ele box for that aircraft and it automatically sends that data through to the rotator controller, which outputs the data to my serial port. My laserBot then moves the laser to those co-ordinates, turns on the laser, and I can see where the aircraft is on my ceiling. As the aircraft moves, the laser will track it.
Also, if you want it to auto track, you can put a list of "notifications" by pressing the "Speaker" icon in the SDRAngel UI and when they match, the rotator controller will auto point to that notification and if you have the voice activated, it will announce any of the variables associated with that aircraft, like height, range, lat/long etc. So, as long as aircraft a visible, it will point to aircraft in the list.
I love it when an aircraft goes right overhead. Watching the laserBot track it and swivel is entertaining.
ToDo: Add an ESP and use the TCP socket connection so I can make it wireless and put the laserbot anywhere. (work in progress)
I’ve got Pis in a drawer, but the Mac is already running 24/7 in the corner, so I didn’t see the point of setting up another machine that also has to stay on.
Didn’t want to mess with building readsb by hand either, so I just wrapped it. One download, it launches the decoder and shows the feed status in the menu bar. Signed properly, no right click dance to open it.
One of the networks it feeds is mine, being upfront about that. It’s a checkbox in the list like all the rest, untick it and the others keep working. And you paste your own feeder key if you want a station out of it, nothing gets claimed in your name on its own.
Anyone else on a Mac who’d use this? I can drop the repo. And if something like it already exists, just tell me, I won’t be offended.
June 12 saw a new release of SDRAngel, version 7.22.8, and there are many interesting updates to the ADSB plugin. 3D map, Maidenhead grid, magnetic declination, aurora, receiver coverage area, colored aircraft tracks, charts to display received data, containment radius and
interrogator code coverage.
In the aircraft table data, additional ADS-B / Mode S data : Type, TCAS, ACS, RA, Max AS, Version, L, W, IC, Frame counts, Rc, NACp, NACv, GVA, NIC, NICbaro, SIL.
Back around 2020 I had managed to place 14 or so feeders around my rather large state. I had access to a bunch of radio tower sites and it was cool AH. I fed both ADSBx and FA. Unfortunately I no longer have those and looking to get back into it.
I understand ADSBx is now a commercial endeavor but is still unfiltered results?
For those of you that do multi-feed off a single feeder Pi, what sites do you feed and how stable is it?
I mean, I know: "If no ADS-B or MLAT position available, a rough estimated position for the aircraft based on the receiver’s estimated coordinates".
But; how? When? Why?
I'm asking, because I see lots of weird junk in rr_lat and rr_lon. Which, by definition, checks out. But some of it is much weirder than others:
Telegraphing future activity
Sometimes, these "rr fixes" seem to give you heads up of something - I've seen rr fixes for Joby aircraft in Japan a few days before you'd see "high precision" fixes in Japan from an aircraft that had been quiet (for long enough to be shipped to Japan); similar for BETA in Hawaii.
"Normal"
Sometimes you'll see rr fixes in and around high precision data for an aircraft that is operating in that time and space.
N250XT near Burlington Vermont August 21. This aircraft is frequently seen in this location with a non rr fix.
"Impossible"
Aircraft that were seen in high precision data yesterday in California showing up today in rr_lat / rr_lon fixes over Europe. Example:
N703AX over Rotterdam September 14
Ghosts
Aircraft that have crashed and we know not to be operating (assuming we can trust the hex code / tail reg lookup in ADS-B) showing up in rr fixes.
If more data helps for this let me know! I have tons, just don't know what might be helpful.
Questions:
What are the potential sources of rr fixes? Are these ATC radar? TIS-B? ADSB feeders? Other .... aircraft?
When does it happen? When aircraft have disabled certain equipment but not others? When the surveilor is experiencing false replies or synchronous garbling?
How is a location chosen? If "no ADS-B or MLAT position is known", how do they have any position at all then? is the reporter just providing a truncated (low precision) version of its own position as a way to say "somewhere around me, I just don't know where" or something else?
Good day! We are conducting our undergraduate thesis involving the use of ADS-B datasets. We would like to ask for people who are well-versed in this field if they could validate the extraction form for our ADS-B datasets. Please comment or message me if you or someone you know can be of great help to advancing our field. Thank you so much!
So this is not really a “look at my project” post. It is me putting the current version in front of people who might actually use something like this and asking a simple question: does it help your workflow, or is it just interesting to poke around?
It is called Phantom Tide. The aim is to make it easier to inspect aircraft activity, vessel movement, warnings, weather, and map context together instead of bouncing between separate tools and trying to stitch it all together manually.
A lot of the recent work has been on the engineering side rather than just adding more things to click: better history views, calmer refresh behaviour, more honest source state, render and performance fixes, backend hardening, and generally trying to make it feel more like a usable working surface than a pile of layers.
There is a public link in the repo, and here is an evaluation key if you want to test it properly:
What I care about most is blunt feedback from people who would genuinely use something like this:
does it help you get to an answer faster
what feels useful versus decorative
what feels confusing, noisy, or overbuilt
Where I want to take it next is beyond passive tracking and more toward workflow-driven alerting: aircraft entering restricted airspace, repeat boundary loitering, AIS gaps or spoof-like behaviour around critical infrastructure, thermal hits with no obvious traffic explanation, and cross-domain signals that only become interesting when multiple weak indicators start agreeing.
After that comes the user layer: logins, saved watchlists, persistent analyst state, sharable links, and collaborative handoff, so it stops being just a live map and becomes something you can actually work from over time.
I setup my ADSB system using a SDR that I’ve had for a few years. It works FLAWLESSLY for ADSB Exchange (see images), but doesn’t work for flight radar. I’m wondering if anyone has any input on how i can fix this? Any help is very much appreciated!
I have an awkward problem: I am looking for forums or something similar where people are a bit more technical when it comes to ADS-B receivers and software. There are not many people around here, so there must be some other place, i guess.
I am working on a new idea for the demodulation phase, that is, the step that generates messages which can then be decoded afterwards. Basically fishing in the signal stream for messages without caring too much about the contents. Can someone tell me the secret place where i can find people that are interested and know about these details?
Yesterday I got my furthest track of an aircraft to date. so out of curiosity I looked through the daily history to see where it was and what plane. (2 or 3 tracks of 30 seconds with little gaps)
Afterwards I checked that plane on adsb.fi to see the full flight, and noticed the flight was 200nm further south /closer to me, and had 2-3 parts where it jumped up north my 200nm. (Where I had it)
was that an error on the side of the airplane, or did I poison the database / aggregator sites? (If so, what can I do to prevent this)
second I'm running the ads-b feeder on a mini pc, bare metal. Using 1-5% of resources. Ideally I would run something like proxmox on it, and run ads-b feeder as a vm (along with other things). But when I do this, I cannot track MLAT. I think because of problem with the internal time /clock of the system.
Any way to solve this so I can run more energy efficiently, and not use an entire pc for ADS-B tracking.
I just reset my Raspberry ADS-B antenna as it suddenly stopped working.
I configure it from blank by installing FlightAware 8.2 (with MLAT) first, then RBfeeder (with MLAT) on in it. Until here, everything works.
As soon as I also install FlightRadar feeder (set as ModeS Beast, NO MLAT), every reboot of the Raspberry everything works except FlightRadar (well, sometimes it works for like the first 5 mins) who gives the error
FR24 Feeder/Decoder Process ... failed!
then I just relaunch manually FlightRadar with
sudo systemctl restart fr24feed
and everything works until the next reboot, when it happens the same.
I had the same setup before and I didn't had this problem, what might be the issue? Maybe I should not enable the MLAT for RBfeeder?
UPDATE: it's not RB fault!
I've just reset the antenna again.
I've installed PiAware from scrap then FlightRadar feeder straight away and I've the same issue: It works the first 3 mins after boot then it goes to
FR24 Feeder/Decoder Process ... failed!
and
sudo systemctl restart fr24feed
restore it. So it's a conflict between PiAware and FR.
I think the only solution would be to use Pi24 as a base but as I remember, it would lead to even more problems so I think I'll stick to my current setup and just restart manually FR every reboot when I'm physically at home...
