Flight tracking on your PC: tar1090 vs. Virtual Radar Server

Flightradar24 on your phone shows you the sky of the whole world. But as soon as you have your own ADS-B receiver on the roof or the windowsill, you want to know what your antenna is hearing right now – unfiltered, without delay and with trails that show how far your reception reaches. For that you need a web interface that translates your decoder’s raw data into a map. Two names come up again and again: tar1090 and Virtual Radar Server. This comparison shows you how the two differ, which solution suits whom and how to combine them sensibly.

The short answer

tar1090 is the lean, actively maintained map interface that runs directly on your Raspberry Pi next to the decoder. For a single home receiver, it is almost always the first choice. Virtual Radar Server (VRS) is a standalone server for Windows and Linux that merges several data sources, maintains its own aircraft database and creates reports. It is worthwhile if you run more than one antenna or want to analyze your sightings over the long term – in return you accept an older codebase and more setup effort.

First, sort things out: decoder, interface, feeder

Anyone new to the topic quickly mixes up three layers. Separating them makes the decision much easier.

• Receiver: An antenna plus an SDR stick pick up the transponders’ radio signals on 1090 MHz. Which sticks are suitable is shown in the comparison of SDR sticks for ADS-B; the complete setup is described in the guide Building your own ADS-B receiver.
• Decoder: Programs such as readsb or dump1090-fa convert the signals into readable data – ICAO address, callsign, altitude, position, speed. How Mode S and ADS-B work technically is explained in the article Transponder modes A, C and S.
• Interface: tar1090 or Virtual Radar Server fetch the decoded data and draw it on a map. This layer is exactly what this article is about.

There are also feeders such as fr24feed or PiAware, which send your data to networks like Flightradar24 or FlightAware. They run independently of the local interface. So you can feed without any problem and still look at your own map – more in Setting up fr24feed and Installing PiAware.

tar1090 in detail

tar1090 comes from the developer wiedehopf, who also maintains a widely used fork of readsb and the graphs1090 statistics charts. The project describes itself as an improved web interface for the decoders readsb and dump1090-fa. According to the project page, it only works to a limited extent with dump1090-mutability.

Installation and access

A single script for Debian-based systems such as Raspberry Pi OS, Debian or Ubuntu takes care of the installation. Afterward you reach the map on your home network at an address following the pattern http://<IP-of-the-Pi>/tar1090. The same script is also used for updating. You can find a step-by-step guide including the decoder in the guide Installing readsb and tar1090.

What tar1090 can do

• Flight trails: For every aircraft, tar1090 draws a track whose length you can set. With “show all tracks” you see at a glance where the approach routes run over your location.
• Range outline: Using a panorama from heywhatsthat.com, tar1090 overlays the theoretical radio range of your location as an outline. That way you compare real reception with what the terrain allows.
• Heatmap: Together with wiedehopf’s readsb fork, you can generate a heatmap that shows where traffic concentrates over time.
• Filters: Type filters work with regular expressions. With them you show, for example, only widebody jets, only certain type designators or only helicopters.
• Multi-select and labels: You can mark several aircraft at once and show or hide callsign labels.
• Maps and controls: Several map backgrounds, a dimmable map, keyboard shortcuts and URL parameters with which you can save a fully configured view as a bookmark.
• Extra data: Optionally, tar1090 also shows UAT data on 978 MHz (relevant in the US) and ship positions from AIS-catcher.

Strengths and limits

The biggest strength is its closeness to the decoder: tar1090 reads the JSON files that readsb writes anyway and needs hardly any processing power for it. Even an older Raspberry Pi copes well with it. The interface is fast, shows data without noticeable delay and works equally well on smartphone, tablet and PC. Because many big community trackers build on readsb and tar1090-based interfaces, the controls feel familiar if you already know sites like adsb.fi or adsb.lol – see Community trackers compared.

tar1090 has limits where long-term analysis is concerned. There is no built-in database in which you can search sightings over months, and no reporting function in the classic sense. Merging several receivers at different locations is not its core topic either – for that, solutions such as community networks (see Feeding ADS-B Exchange and community networks) or the Docker stack from the guide Feeding multiple networks with Ultrafeeder come into play.

Virtual Radar Server in detail

Virtual Radar Server is an open-source .NET application that brings its own web server. According to the project page, it was tested with the Kinetic receivers SBS-1er and SBS-3. Today it works with any receiver or decoder that outputs one of the supported formats: the Kinetic text format, the SBS-3 binary format, the AVR formats or the Beast binary format. readsb can output Beast and SBS data, among others – which makes a Raspberry Pi with readsb a suitable source.

Platforms and installation

On Windows you simply run the installer and configure the program via “Tools | Options.” There is a 32-bit and a 64-bit variant. For most Windows users, the developer recommends the 32-bit version; the 64-bit version is mainly worthwhile for feeds with many thousands of aircraft. For Linux there is a package that runs under the Mono runtime. By default, the web server listens on port 8080 there, and you reach the map at an address following the pattern http://<IP>:8080/VirtualRadar/. Under Mono, the path is case-sensitive according to the documentation. Without a graphical interface, the server can be started with the parameter -nogui; you then do the configuration via the Web Admin plugin. The details are in the guide Setting up Virtual Radar Server.

What Virtual Radar Server can do

• Several receivers: In the options you create any number of data sources along with their location.
• Merged feeds: Two or more feeds can be merged into one common feed – handy if you run antennas at two locations or pool data with spotter friends.
• Rebroadcast server: VRS can pass feeds on to other VRS instances or decoders.
• BaseStation database: Through the Database Writer plugin, VRS writes flight movements to an SQLite database in BaseStation format. If no database is configured, the reports stay empty, and details such as registration, type and operator are missing unless the aircraft sends them itself.
• Online lookups: Optionally, VRS fills in missing details such as registration, manufacturer, model, operator and year of manufacture via an online service.
• Pictures, logos and silhouettes: You can configure folders with your own aircraft photos (named by ICAO address or registration), airline logos and type silhouettes. For spotters who want to include their own pictures, this is appealing. How to match photos with reception data afterward is shown in Matching sightings with ADS-B logs.
• Plugins: Besides Database Writer, there are Web Admin, Tile Server Cache, Custom Content and a database editor, among others.
• Flight simulators: Without a receiver, VRS shows aircraft from Microsoft Flight Simulator X, Microsoft Flight Simulator 2020 or X-Plane if it runs on the same computer.

Strengths and limits

VRS is the tool for people who do not just want to look at data but manage it. The database connection, custom picture folders and merged feeds go well beyond what tar1090 aims to do as a pure map interface. The catch is its age: according to the official download page, the current version 2.4.4 dates from December 2019, and most plugins are even older. The source code is public on GitHub. For a new installation on Linux you have to set up Mono and, if necessary, apply workarounds from the documentation, for example for errors with the SQLite connection.

tar1090 and Virtual Radar Server head to head

Criterion	tar1090	Virtual Radar Server
Type	Web interface for a decoder	standalone server with web interface
Platform	Debian-based systems (Pi OS, Debian, Ubuntu)	Windows, Linux via Mono
Data source	readsb or dump1090-fa	Beast, AVR, Kinetic SBS formats, flight simulators
Several receivers	not a focus	merged feeds built in
Flight trails	yes, adjustable	yes
Heatmap	with wiedehopf’s readsb fork	not documented
Range outline	via heywhatsthat.com	not documented
Database and reports	no	BaseStation database via plugin
Own photos and logos	no	folders for pictures, logos, silhouettes
Development	actively maintained	official version 2.4.4 from 2019
Effort	low	medium to high

Which solution suits you?

How to combine both

You do not have to decide. readsb outputs its data through several network ports at once, including Beast, SBS/BaseStation and JSON. A typical setup looks like this:

Other interfaces you should know

Besides the two classics, there are alternatives you keep running into in forums:

• SkyAware from FlightAware: dump1090-fa comes with its own browser map. If you use PiAware, you find the direct link to it on your FlightAware statistics page. It is perfectly sufficient to get started, but tar1090 offers more settings.
• PlanePlotter: COAA’s Windows software also decodes ACARS and HFDL besides ADS-B and offers multilateration in cooperation with other users. After a 21-day trial period, a paid license is required according to the manufacturer’s page. How MLAT works is explained in the article Multilateration explained, and receiving data link is described in Receiving ACARS with an SDR.
• Big online trackers: If you only want to track on a PC without your own receiver, the classic flight tracking services are the right choice – the flight tracking apps comparison gives an overview.

What to watch out for

• Do not expose it to the internet unprotected. Both interfaces are meant for the home network. If you want to access them on the go, use a VPN connection instead of open ports on the router.
• Enter the location correctly. Without the receiver position, distance figures and range analyses are wrong – with graphs1090 the range graph does not work at all otherwise.
• Know the legal situation. Reception is a common hobby practice in Germany, but passing on data raises its own questions. Receiving ADS-B data: the legal situation gives an overview.
• The antenna decides. No interface conjures up aircraft your receiver cannot hear. If the map stays empty, it is almost always down to the antenna, location or cable – the guide Finding the best antenna location gives tips.
• Understand the symbols. Colors, icons and data fields differ between interfaces. What the displays typically mean is explained in Flight tracker symbols and colors.

Conclusion

tar1090 and Virtual Radar Server solve the same basic problem – turning your receiver’s data into a map – but pursue different goals. tar1090 is lean, fast and closely tied to readsb. For a single home receiver, there is hardly a reason not to start with it. Virtual Radar Server is the older, more broadly positioned tool with merged feeds, a database and its own picture folders. If you want to bundle several antennas or archive sightings over the long term, you find features there that tar1090 deliberately does not offer. Since readsb can feed both at the same time, the combination is often the best solution.