SDR sticks for ADS-B compared: RTL-SDR Blog, FlightAware, Nooelec, Airspy

A Raspberry Pi is quickly bought, and so is an antenna – but the receiver itself is where things get confusing. Cheap DVB-T sticks, FlightAware sticks with a built-in preamp, aluminum housings from Nooelec, and the Airspy as the pro option: if you are looking for an SDR stick for ADS-B, you will find dozens of variants that at first glance all do the same thing. This comparison shows you how RTL-SDR Blog, FlightAware Pro Stick, Nooelec NESDR and Airspy differ technically, what the datasheet values really mean for reception on 1090 MHz and which stick suits which location.

The short answer

For a pure ADS-B station, a stick with a built-in preamp and 1090 MHz filter like the FlightAware Pro Stick Plus is the most convenient choice: plug it in, start the feeder image, done. If you also want to use the stick for aviation radio, ACARS or other frequencies, an all-rounder like the RTL-SDR Blog V4 or a Nooelec SMArTee is the better basis – supplemented with an external preamp at the antenna if needed. An Airspy Mini is the premium class for feeders whose antenna is already ideally placed and who want to get even more messages out with more processing power.

How a complete receiver is built is explained in the guide Building an ADS-B receiver yourself. This one is only about the heart of it: the stick.

What is inside an SDR stick

Almost all inexpensive sticks go back to the same discovery: hobbyists found out that the raw radio data can be read out of mass-produced DVB-T TV sticks with the RTL2832U chip. The TV receiver thus became a universal software-defined radio – the RTL-SDR. The actual signal processing is done by software on the computer.

At its core, an RTL-SDR consists of two building blocks:

• Tuner: It converts the antenna signal to an intermediate frequency. Common are the tuners of the R820T family (R820T2, R860) as well as newer variants like the R828D. According to RTL-SDR.com, R820T tuners cover roughly 24 to 1766 MHz – 1090 MHz is comfortably within that.
• RTL2832U: It digitizes the signal with an 8-bit converter and sends it to the computer over USB. RTL-SDR.com estimates the effective resolution at about 7 bits and the maximum sample rate at 3.2 million samples per second, with no samples lost up to 2.56 MS/s.

The 8 bits are the Achilles heel: a strong signal – such as an aircraft directly overhead or a nearby cell tower – and a very weak signal from a distant aircraft have to fit into this small value range at the same time. If the gain is too high, the stick overloads; if it is too low, the distant signals drown in the noise. Almost all differences between the sticks revolve around mitigating this problem.

The features that matter for ADS-B

Feature	What it does	Importance for ADS-B
Built-in LNA	amplifies the signal right at the input before the tuner adds noise	high, especially with a long cable or weak tuner
1090 MHz filter	lets only the ADS-B band through	high in cities and near transmitters, often unnecessary in the countryside
Bias tee	supplies power through the antenna connector to an external LNA	high if you use a mast preamp
TCXO	stabilizes the frequency against temperature drift	low to medium, more important for narrowband radio
Metal housing/cooling	dissipates heat, shields against interference	medium, relevant in 24/7 continuous operation
ADC resolution	dynamic range of the converter	high, the main advantage of the Airspy models

RTL-SDR Blog V4: the all-rounder

The sticks from RTL-SDR Blog are considered the reference among all-round RTL-SDRs. The current main model, the V4, uses according to the manufacturer the R828D tuner, a TCXO with 1 ppm and a bias tee with 4.5 volts that can be switched on and off in software and continuously delivers up to 180 mA. The aluminum housing cools passively via a thermal pad. Compared with its predecessor, the V3, the V4 has improved input filtering and, according to RTL-SDR.com, is less prone to being overloaded by strong broadcast transmitters. It receives shortwave via a built-in upconverter.

For ADS-B that means: without extra parts the V4 is a solid receiver, but not a specialist – it lacks a preamp and bandpass filter specifically for 1090 MHz. Its strength is flexibility. Through the bias tee you power an LNA with a filter directly at the antenna, and the stick is suddenly playing in the league of the ADS-B specialists. Suitable LNA-filter combinations for 1090 MHz are available from several vendors, including from the RTL-SDR ecosystem itself. How to build such a chain is described in the guide Increasing ADS-B range with an LNA and filter.

Two things you should know: the V4 needs updated drivers – according to the manufacturer it does not work correctly with old RTL-SDR drivers. So check whether your decoder or feeder image ships with a current driver version. In addition, the manufacturer now also offers a V4L variant with the R828S tuner and a simpler input diplexer, for which it states better sensitivity; it also needs newer drivers.

FlightAware Pro Stick and Pro Stick Plus: the specialists

FlightAware developed its sticks specifically for its own feeder stations. Both models use the R820T2 tuner, a built-in preamp with 19 dB gain and a 0.4 dB noise figure, a TCXO with 0.5 ppm and an SMA connector. According to the datasheet, they draw about 300 mA from the USB port.

• Pro Stick: Preamp without a filter. FlightAware cites a range increase of 20 to 100 percent for Mode S messages compared with conventional RTL-SDR sticks.
• Pro Stick Plus: additionally a bandpass filter for 1075 to 1105 MHz with 2.3 dB insertion loss that suppresses signals outside the band by 30 dB. Where filtering helps, FlightAware states 10 to 20 percent more Mode S messages.

The built-in preamp has a downside: it amplifies everything, including interfering signals. With the Pro Stick, FlightAware explicitly advises using a 1090 MHz filter and/or reducing the gain in the decoder. That is exactly what the Plus is for. For rural locations with no strong transmitters nearby, FlightAware, on the other hand, generally advises against filtering.

The Pro Sticks work not only with PiAware but with any RTL-SDR software – so also with readsb or the feeders of other networks. Because the filter and LNA are tailored to 1090 MHz, the Plus in particular is hardly suitable for other frequencies. 978 MHz (UAT) also falls through the filter, which does not matter in Europe, though; the article UAT on 978 MHz explains why.

The last point is important: a preamp works best before the cable losses, meaning directly at the antenna. With a roof antenna and a long coax cable, an external LNA at the mast therefore usually gets more out of it than the LNA in the stick.

Nooelec NESDR: many variants, a solid base

The manufacturer Nooelec offers a whole family of RTL-SDR sticks under the name NESDR. All are based on the RTL2832U; the differences lie in tuner, housing, clock source and bias tee. For ADS-B, these models are the most relevant (prices according to the Nooelec shop in US dollars, as of October 2026):

Model	Special feature	TCXO	Bias tee	Price per shop
NESDR SMArt v5	R820T2/R860 tuner, aluminum housing, 100 kHz to 1.75 GHz	0.5 ppm	not specified	$54.95
NESDR SMArTee v2	R820T2, aluminum housing	0.5 ppm	yes	$44.95
NESDR SMArTee XTR	extended frequency range, aluminum housing	0.5 ppm	yes	$54.95
NESDR Nano 3	very small, aluminum housing with its own heat sink	0.5 ppm	not specified	$52.95
NESDR Mini	simple basic stick with R820T	not specified	not specified	$44.95

For a stationary ADS-B station with a mast LNA, a SMArTee is the obvious choice because it can power the preamp through the bias tee. The models without a bias tee work just as well – then you either need no external LNA or a separate power injector. The Nano 3 is popular thanks to its size when the stick plugs directly into a laptop or smartphone; for mobile use at the fence, take a look at the guide Mobile ADS-B reception at the spot. The XTR models with extended frequency range bring no advantage for 1090 MHz – they are more interesting for users who also want to listen above 1.7 GHz.

Without a built-in ADS-B LNA, the Nooelec sticks are roughly on the level of other good RTL-SDRs in basic performance. Their strengths are solid build quality, metal housings and precise clock sources.

Airspy Mini and R2: the premium class

The Airspy receivers play in a different league. Instead of an 8-bit converter, they use a 12-bit ADC with 20 MSPS, according to the manufacturer with 10.4 effective bits and 95 dB spurious-free dynamic range. That means strong and weak signals fit into the value range at the same time much better – exactly the problem RTL-SDRs most often fail at with ADS-B.

	Airspy Mini	Airspy R2
Frequency range	24–1700 MHz	24–1700 MHz
Converter	12 bit, 20 MSPS	12 bit, 20 MSPS
IQ output rates	10, 6 or 3 MSPS	10 MSPS, experimental 2.5 MSPS
Bias tee	4.5 V, via software	4.5 V, via software
Clock	0.5 ppm	0.5 ppm, external clock input 10–100 MHz

For ADS-B, the Airspys are used with the special decoder airspy_adsb, which passes the data on to readsb or dump1090-fa. The common community configuration (airspy-conf by wiedehopf) works with 12 or 20 MSPS. On the Mini, 20 MSPS is not officially supported according to this guide, more easily causes MLAT problems and brings only a small gain over 12 MSPS – less than three percent more positions at a much higher CPU load. You set the gain in steps from 0 to 21, with each step corresponding to about 3 dB.

The catch is obvious: an Airspy costs several times as much as an RTL-SDR stick, and airspy_adsb puts noticeably more load on the processor than an RTL decoder. On older or very small single-board computers it gets tight. What that means in practice and how to set up the configuration is explained in the guide Airspy Mini/R2 for ADS-B. If you are thinking about alternatives to the Raspberry Pi, ADS-B reception without a Raspberry Pi helps.

All four head to head

Criterion	RTL-SDR Blog V4	FlightAware Pro Stick Plus	Nooelec SMArTee	Airspy Mini
Converter	8 bit	8 bit	8 bit	12 bit, 20 MSPS
Basis	RTL2832U + R828D	RTL2832U + R820T2	RTL2832U + R820T2	own platform with R820T2 tuner, without RTL2832U
Built-in LNA	no	yes, 19 dB	no	no
1090 MHz filter	no	yes	no	no
Bias tee	yes, 4.5 V	no	yes	yes, 4.5 V
TCXO/clock	1 ppm	0.5 ppm	0.5 ppm	0.5 ppm
Other frequencies	very good	hardly	very good	very good
CPU load for ADS-B	low	low	low	high
Strength	Flexibility	Plug-and-play for ADS-B	Build quality, variants	Dynamic range

The table describes the stick alone. In practice, it is the chain that counts: antenna, cable, possibly LNA and filter, stick, decoder. An RTL-SDR Blog V4 with a mast LNA can clearly outperform a Pro Stick Plus with a window antenna – and a badly placed antenna holds back even an Airspy.

Setting the gain correctly

Whichever stick: the gain setting has a say in the result. Too much gain overloads the converter, nearby aircraft get distorted and interfering signals flood the input. Too little gain costs range.

• readsb uses its own autogain algorithm by default with RTL-SDR sticks, which according to the project description is optimized for ADS-B. For getting started, that is a good starting point; installation is described in the guide Installing readsb and tar1090.
• Sticks with a built-in LNA like the Pro Stick usually need a lower software gain than simple sticks.
• With the Airspy, according to airspy-conf, you raise the gain step by step from the minimum until the strongest aircraft sit just below 0 dBFS.

Whether a change does anything is not something you see from gut feeling but in your station’s statistics: message rate, number of positions, range plot. How to evaluate them is shown in Measuring reception performance with graphs1090. Always change only one parameter and observe for at least one day with normal traffic.

What to look for when buying

• Antenna first, then the stick. A higher, clearer antenna location almost always brings more than a stick upgrade. Tips are in Finding the best antenna location and Building a 1090 MHz antenna yourself.
• Be careful with no-name sticks. Cheap DVB-T sticks without a TCXO and metal housing often work, but they drift more, get hot and are shielded worse. For a 24/7 feeder, the small extra cost for a brand-name model is worth it.
• Don’t switch on the bias tee by accident. If voltage is present on the antenna connector although only a passive antenna or a splitter is attached, you risk damage. Switch it on only when an LNA really depends on it.
• Mind the USB power supply. Sticks with a built-in LNA draw noticeable current. A weak power supply on the Raspberry Pi leads to dropouts.
• Check the driver version. Newer sticks like the RTL-SDR Blog V4 need current drivers. Older images or programs may not detect them correctly.
• Several networks, one stick. You do not need a second stick to feed several flight tracking services. How that works is explained in Feeder programs compared and Feeding several networks with Ultrafeeder.

If you do not want to tinker at all, the article Buying a ready-made ADS-B receiver offers complete solutions where stick, computer and software already fit together. And because a good stick also provides the basis for MLAT calculations, it is worth a look at MLAT explained.

Conclusion

For ADS-B on 1090 MHz you do not need an expensive receiver – almost any good RTL-SDR stick decodes the signals reliably. The differences are in the details: the FlightAware Pro Stick Plus comes with preamp and filter from the factory and is thus the simplest solution for a pure ADS-B station. The RTL-SDR Blog V4 and Nooelec SMArTee are flexible all-rounders that draw level with an LNA at the antenna and also receive aviation radio or ACARS on the side. The Airspy Mini is the choice for feeders who have maxed out their antenna and want to get the maximum out with more dynamic range and processing power. What data you may receive and pass on with your station is covered in the article on the legal situation of ADS-B reception.