Setting up Virtual Radar Server: your own radar display on Windows

Online flight trackers are handy, but they show you what a provider wants to show – with a delay, with ads and often with filters behind a paywall. If you run your own ADS-B receiver, there is another way: Virtual Radar Server turns your raw data into a full-fledged radar display in the browser, with your own database, your own photos and filters that you define yourself. This guide shows you how to set up VRS on Windows, connect your receiver, pull in registrations and types and use the map on your home network or on the go.

What Virtual Radar Server is – the short answer

Virtual Radar Server, usually just called VRS among spotters, is a free open-source program for .NET, developed by Andrew Whewell. It connects to one or more Mode S or ADS-B receivers, decodes their data and starts a small web server. You then see the aircraft in any modern browser on a map, plus a sortable list with all the details.

Important for your expectations: VRS is not a receiver. It needs a data source – such as an SDR stick with dump1090 or readsb, a ready-made receiver or a classic Kinetic receiver. How to build such a station is covered in the guide Building your own ADS-B receiver. Without a receiver, VRS can only display aircraft from Microsoft Flight Simulator or X-Plane when it runs on the same computer.

You should know the state of development honestly: according to the official download page, the last stable version 2.4.4 is from December 20, 2019. Pre-releases of version 3 appeared until February 2023. That makes VRS a mature but only sporadically maintained tool. For many spotters it is still the first choice because it bundles database, reports, pictures and filters in one package. A comparison with the leaner web interface tar1090 can be found in the article Desktop flight tracking with tar1090 and Virtual Radar.

What you need beforehand

Before you install, sort out three things:

• Data source: A running decoder that provides its data on the network. With dump1090 and readsb that is the default. How to set up readsb is described in the guide Installing readsb and tar1090; which SDR stick is suitable is shown in the SDR stick comparison.
• A computer for VRS: A Windows PC that runs around the clock if possible. Alternatively, a Linux machine with Mono works too, more on that below.
• The receiver’s IP address: Note down the address of your Raspberry Pi or ready-made receiver on the home network. It is best to assign a fixed address in the router, otherwise VRS loses the connection after a restart.

Data format in VRS	Typical source	Typical port	Note
BaseStation	dump1090, readsb, Kinetic receivers	30003	text format, supported by almost every decoder
AVR or Beast Raw	dump1090, readsb, Beast-compatible receivers	30005 (Beast)	VRS detects on its own whether AVR or Beast arrives and decodes the raw data
SBS-3 Raw	Kinetic SBS-3	30006	binary format
Plane Finder Radar	Plane Finder receivers	depends on the device	raw format of the Plane Finder receiver
Compressed VRS / Aircraft List (JSON)	another VRS instance	freely selectable	Compressed VRS is only sent by VRS rebroadcast servers

Many spotters choose the Beast raw data because VRS then decodes it itself. The BaseStation format on port 30003, on the other hand, is the most straightforward and works practically every time.

Installation on Windows

The official download page offers two installers: a 32-bit and a 64-bit installer. The developers recommend the 32-bit version for most Windows users. The 64-bit variant needs more memory and cannot load 32-bit third-party libraries, which causes individual features to fail. It only pays off for feeds with many thousands of aircraft – so hardly for a home station.

In current versions, the map uses Leaflet with freely usable map tiles – the Tile Server Cache plugin builds on that too. Google Maps can be integrated as an alternative but requires your own API key, and Google bills use of its maps API by volume. For a private radar display, the simplest option is to stay with Leaflet.

Connecting the receiver as a Receiver

The actual work happens in the Options under Receivers. There you create an entry for each data source:

• Name: freely selectable but must be unique – for example “Attic” or “Balcony Pi”.
• Format: the matching data format from the table above.
• Connection type: “Network” for receivers on the home network, “Serial” for older devices on the COM port.
• Address and Port: the receiver’s IP address and the port it sends on.
• Visibility: “Normal” shows the feed on the web page, “Hide from web site” hides it, “Merge only” uses it only in merged feeds.

VRS establishes the connection itself on startup and retries every second if it drops. If the status window permanently shows no active connection, the address, port or format is usually wrong. An idle timeout helps with unstable connections: if no data arrives for a certain number of seconds, VRS restarts the connection.

For special cases there is the Push Receiver: VRS then waits on a port until the other side sends data – handy if a receiver at another location sits behind a router and is supposed to push its data to you actively. In this mode you can use allow and deny lists to define which IP addresses may connect.

Combining several receivers: merged feeds

If you run more than one antenna, say one at home and one at a friend’s place closer to the airport, a merged feed combines both into one view. A receiver can be part of any number of merged feeds, but merged feeds cannot be nested inside each other.

The logic behind it: for each aircraft, VRS “locks on” to the receiver that reported it first. Only when that one goes silent for the configured ICAO timeout does the next one take over. If the value is too short, aircraft jump back and forth with a receiver that has a delay. If it is too long, they seem briefly frozen. For connections with little delay, the documentation gives about one second as a guideline; for connections with a lot of delay you should raise the value.

If a receiver delivers MLAT positions, you can mark it as an MLAT source in the merged feed. VRS then also adopts its calculated positions for aircraft that actually belong to another receiver. How multilateration works and why it makes aircraft without an ADS-B position visible is explained in the article MLAT explained simply.

Databases: turning hex codes into registrations

An ADS-B signal contains the ICAO 24-bit address, callsign, position, altitude and speed – but neither registration nor aircraft type nor operator. VRS fills this gap in two ways.

Online lookup

In the Data Sources options you can enable the online lookup. VRS then fetches registration, manufacturer, model, operator, year of manufacture and serial number for aircraft that are not yet in your local database. For getting started, that is entirely sufficient.

The BaseStation database

VRS gets really powerful with your own SQLite database in BaseStation format (BaseStation.sqb). Without it, the reports stay empty. The file is created either by Kinetic’s BaseStation program or – for everyone else – by the Database Writer plugin:

1. Open the plugin under Tools › Plugins and enable it.
2. Enter a file name or choose “Use default filename” and create an empty database via “Create Database”.
3. Select the receiver or merged feed the plugin should log – it can only record one source at a time.
4. Optionally enable “Save online lookups in database” so that looked-up registrations end up permanently in the database.

The option “Overwrite details on existing aircraft” refreshes online data for entries older than 28 days. If you maintain records by hand – for example with the Database Editor plugin – better leave it off, otherwise the online lookup overwrites your corrections. Through the database you can also mark aircraft as “interesting” and filter for them later.

Photos, flags and silhouettes

Three more folders make the display more personal:

• Pictures folder: Pictures in JPG, PNG, GIF or BMP format, named after hex code or registration. For both, the hex code takes priority. If you like, VRS also searches subfolders. Ideal for seeing your own spotter photos next to the live position – provided your files are named cleanly. Tips are in the article Labeling photos properly.
• Flags folder: Airline logos as BMP, named after the ICAO operator code.
• Silhouettes folder: Type silhouettes as BMP, named after the ICAO type code such as A320 or B738.

Filters: how to find the interesting aircraft

On a day with a lot of overflight traffic you quickly see hundreds of aircraft. VRS’s filters separate the exciting from the everyday. According to the technical documentation, the Aircraft List interface supports these criteria, among others, which you can combine in the web interface:

Filter	What it is good for in everyday spotting
Callsign	specific flight numbers or callsign prefixes such as freighters or ambulance flights
Registration and hex code	follow a specific aircraft, such as a special livery (Tracking an aircraft by registration)
ICAO type code	show only A388, B748 or other rarities (ICAO type codes explained)
Operator and operator ICAO code	filter out one airline
Altitude and distance	only traffic below a given altitude or within a radius of your spot
Squawk	narrow down certain transponder codes, such as the emergency squawks 7500, 7600 and 7700
Military	show or hide aircraft recognized as military
Interesting	aircraft marked in the database
Aircraft class, engine type, wake turbulence category	for example only helicopters or only heavy jets
Country, airport, custom tag	country, departure, destination or intermediate airport of the route, tags you assigned yourself

All filters are combined with AND and can also be inverted. That way you can build, for example, a view of “heavy jets within 30 kilometers, but not airline X”. For hunting grays there is the military filter; what to keep in mind with military traffic is in the guide Tracking military aircraft online. How transponder codes come about is explained in the post Mode S transponders explained.

Reports: your logbook in the background

Once the database is running, VRS logs every flight your receiver picks up. In the Reports of the web interface, you can later search specifically for past flights, for example for a particular aircraft or time period. That lets you answer questions like “Was the freighter really here last night?” or “How often does this registration show up in my area?”. For spotters this is gold for assigning your own photos to a flight after the fact – how to do that systematically is described in the article Matching sightings with ADS-B logs.

Access on the home network and from the internet

The status window shows three addresses: for your own computer, for the home network and for access from the internet. On the home network, you simply open the map on a tablet or smartphone – there is a desktop and a mobile view.

For access on the go, VRS can set up a port forward in the router via UPnP. Separate restrictions apply to users from the internet: reports and aircraft photos are blocked for them by default, while speech output, labels and range plots can be allowed or forbidden individually. You can also require visitors to log in.

If you share, do it only with a login. It is safer to reach the map via a VPN into your home network rather than through an open port. And before you make your data publicly accessible, read the article on the legal situation of receiving and sharing ADS-B data.

VRS on Linux and the Raspberry Pi

If you do not want to keep a Windows computer running around the clock, you start VRS via Mono. For that, you install the Mono runtime (on Debian and Ubuntu, for example via the package mono-complete), unpack the Mono archive from the download page and start the program. With the parameter -nogui, VRS runs without an interface; it is then configured via the Web Admin plugin, for which you create an administrator on the command line. Under Mono, VRS listens on port 8080 by default, and the path “VirtualRadar” in the address is case-sensitive there.

A few limitations apply: speech output, UPnP and the connection to Flight Simulator X do not work under Mono, and neither do keep-alive packets – the idle timeout helps here. If your receiver runs on a Raspberry Pi anyway, the combination of readsb and tar1090 is usually the simpler solution. Alternatives to the Pi are presented in the article ADS-B reception without a Raspberry Pi.

Common problems and quick fixes

• No aircraft, connection is up: Check the format. If you set the format “BaseStation” on port 30005, you will get no usable data.
• Aircraft without registration: Check the database path and online lookup in the Data Sources options.
• Reports empty: Without a database there are no reports. Enable the Database Writer and choose the right feed.
• Ground traffic missing: Enter the receiver location and assign it to the receiver.
• Map loads slowly: Install the Tile Server Cache plugin; it caches the Leaflet map tiles locally.
• Less range than expected: That is not a VRS problem but an antenna one. Help is available in the guides on antenna location and on boosting range with an LNA and filter.

Conclusion

Virtual Radar Server is the Swiss Army knife for everyone who wants not just to see their own ADS-B reception but to analyze it. Setup always follows the same pattern: create a receiver with the matching format, enter the location, enable the database and online lookup, build filters. You hardly notice on your home network that the project is barely developed further – so be especially careful when sharing over the internet. If you mainly want a fast live map, tar1090 serves you well; if you value the database, reports and your own photos, you can hardly get around VRS. The bigger picture of how live data improves your spotting planning is described in the guide Flight tracking with ADS-B for spotters.