RTL-SDR vs HackRF vs Airspy: Which SDR Should You Buy?
Which SDR should a beginner buy: RTL-SDR V3, V4 or V4L, HackRF, Airspy or SDRplay? Receive vs transmit, coverage, 2026 prices and our advice for starting right.
For a beginner, the best software-defined radio (SDR) is still a TCXO RTL-SDR at around €35–60. It covers roughly 24 MHz to 1.7 GHz, handles the vast majority of discovery projects and teaches you what you actually enjoy. Stepping up to an Airspy or SDRplay makes sense once you hit its limits. A HackRF only makes sense if you need to transmit in a lab or go above 1.7 GHz.
Here is how to decide, model by model, with prices checked in October 2026.
Receive-only vs transmit-and-receive
This is the first question, before any spec sheet.
- A receiver (RTL-SDR, Airspy, SDRplay) only listens. It has no effect on the airwaves and no transmit rules apply. It is the tool for listening, decoding and amateur radio astronomy.
- A transceiver (HackRF, LimeSDR, ADALM-Pluto and others) can transmit too. That is useful for testing your own projects in a lab: a sensor, a remote, a home-made protocol. But any transmission outside licence-exempt bands and their power limits needs authorisation, and jamming is illegal.
One common belief needs correcting: transmit-and-receive is not "better" than receive-only. The HackRF is designed to cover a huge range, 1 MHz to 6 GHz for the One. That compromise costs it on reception. On common bands it is generally less sensitive and easier to overload than a good RTL-SDR, let alone an Airspy.
If in doubt, start by receiving. We cover the French legal framework in a separate article on SDR legality.
RTL-SDR V3 vs V4: what changed
"RTL-SDR" covers a whole family of dongles built around the Realtek RTL2832U chip. The most-cited ones come from the RTL-SDR Blog brand. According to rtl-sdr.com:
| V3 | V4 | V4L | |
|---|---|---|---|
| Tuner | R860 (R820T2 equivalent) | R828D | R828S |
| Shortwave (HF) | Direct sampling, compromised | Built-in upconverter | Built-in upconverter |
| Filtering | Basic | HF/VHF/UHF triplexer + AM, FM, DAB notches | Diplexer, simpler filtering |
| Oscillator | 1 ppm TCXO | 1 ppm TCXO | 1 ppm TCXO |
| Driver | Any | osmocom 2.0 or later | Recent osmocom |
| Status, October 2026 | Still sold | Discontinued (R828D chips ran out) | Limited edition, ≈ 1 year of stock announced |
The key points:
- The V4 mainly improves shortwave (below 30 MHz) and resistance to strong FM and DAB transmitters. On VHF and UHF, rtl-sdr.com even reports a 2–3 dB sensitivity loss on some bands because of the filtering.
- The V4 is no longer made. The manufacturer says its R828D stock ran out, and that third-party suppliers sold it counterfeit chips. The V4L takes over with an R828S chip. The manufacturer's measurements put it close to the V3: slightly more sensitive, slightly less filtered. A V5 is mentioned for 2027, at an early stage.
- The driver matters. V4 and V4L need a recent driver: osmocom 2.0 or later, which ships with Debian 13 and Ubuntu 24.04 or newer. Our RTL-SDR setup guide walks through it.
On price, rtl-sdr.com's own store lists its dongles at about $35–50 depending on model and accessories. In France, the reseller Passion Radio lists the V4L at €49.92 including VAT (checked October 2026). Be wary of very cheap dongles on marketplaces. They may have no temperature compensation and no shielding, and sometimes counterfeit parts, as the manufacturer itself found.
Do you really need shortwave? For international broadcasting, HF amateurs or time signals, yes. You then need a dongle with an HF upconverter, a long antenna and a quiet location. For aircraft, ships, weather satellites and sensors, no: a dongle covering ≈ 24 MHz – 1.7 GHz, like ours, does the job.
HackRF One, Airspy, SDRplay: when to step up
Airspy R2: serious VHF/UHF reception
The Airspy R2 covers 24 to 1700 MHz, the same range as an RTL-SDR. But it digitises at 12 bits and shows up to 10 MHz of spectrum at once, so in practice it copes far better with strong signals. The manufacturer sells it at around $169 (2026, before tax and shipping to Europe).
Choose it when you live near powerful transmitters, run a serious ADS-B or band-monitoring station, or want to see 10 MHz at once.
SDRplay RSP1B: the best coverage for the money
The RSP1B covers 1 kHz to 2 GHz without an upconverter, with 14-bit resolution, 11 band filters and AM, FM and DAB notch filters. SDRplay lists it at £105.80 excluding VAT (checked October 2026). The pricier RSPdx-R2 adds several antenna inputs.
One limitation: SDRplay's driver and API are free but proprietary, not open source. They work with SDRconnect (SDRplay's own software), SDRuno and third-party programs such as SDR++, but you depend on the vendor.
Choose it when you want shortwave plus VHF/UHF in one receiver with good dynamic range.
HackRF One and HackRF Pro: transmit and very wide coverage
Great Scott Gadgets' HackRF One covers 1 MHz to 6 GHz and samples at up to 20 MS/s with 8 bits. It is half-duplex: it transmits or receives, not both at once. The newer HackRF Pro goes down to 100 kHz, adds a built-in TCXO, and offers 4-bit and 16-bit sampling modes. European reseller Lab401 lists it at €400 (checked October 2026).
Choose it when you develop or test your own radio systems in a lab, work on Wi-Fi, Bluetooth or other bands above 1.7 GHz, or follow a course that requires one. For listening, it is not the best buy.
Budget / coverage / use table
| Receiver | Coverage | Resolution | Visible bandwidth | Transmit | Price checked (Oct 2026) | Best for |
|---|---|---|---|---|---|---|
| TCXO RTL-SDR (V3/V4L type) | ≈ 24 MHz – 1.7 GHz (HF on some models) | 8 bits | ≈ 2.4 MHz | No | ≈ €35–60 | Every beginner |
| Airspy R2 | 24 – 1700 MHz | 12 bits | 10 MHz | No | ≈ $169 ex. tax | Demanding VHF/UHF reception |
| SDRplay RSP1B | 1 kHz – 2 GHz | 14 bits | up to 10 MHz | No | £105.80 ex. VAT | HF + VHF/UHF in one box |
| HackRF Pro | 100 kHz – 6 GHz | 8 bits (4/16-bit modes) | up to 20 MHz | Yes (half-duplex) | ≈ €400 | Lab work, transmit, > 1.7 GHz |
| HackRF One | 1 MHz – 6 GHz | 8 bits | up to 20 MHz | Yes (half-duplex) | Varies by reseller | Lab work, transmit, > 1.7 GHz |
Prices vary with resellers, exchange rates and VAT, so check them when you buy.
One rule worth remembering: the antenna often matters more than the receiver. An RTL-SDR with a well-placed outdoor antenna hears further than a €300 receiver sitting on a desk with its stock antenna.
Our advice: start at €60, then…
- Start with a TCXO RTL-SDR and an adjustable dipole. That is our RTL-SDR receiver (≈ 24 MHz – 1.7 GHz, receive-only, around €60), plus the SDR antenna kit if you want to set the element length for each band.
- Do three or four projects. Our 12 beginner RTL-SDR projects run from FM to Meteor-M weather satellites. You will quickly find what you enjoy.
- Upgrade the antenna before the receiver. A dedicated outdoor antenna, a filter and a shorter cable are the cheapest gains there are.
- Step up based on what you actually need:
- mostly shortwave → SDRplay RSP1B, or a dongle with an HF upconverter;
- overload near transmitters, or a demanding ADS-B station → Airspy R2;
- lab transmission, or bands above 1.7 GHz → HackRF.
Your RTL-SDR won't become useless. Many hobbyists keep one or two for permanent stations, such as ADS-B or sensors, while the main receiver is used for exploring.
Our RTL-SDR will be back in the shop soon: join the waitlist to be notified. As a gift, it is also part of the Hacker Starter Gift Set.
Frequently asked questions
What is the best SDR for beginners?
A TCXO RTL-SDR, around €35–60 depending on the model and the antenna included. It covers most discovery projects (FM, aircraft, ships, sensors, weather satellites) and shows you what you enjoy before you spend more.
Do I need a HackRF to start?
No, unless your specific goal is transmitting in a lab or working above 1.7 GHz. For listening, an RTL-SDR receives better than a HackRF on most common bands, for a fraction of the price.
Is the RTL-SDR Blog V4 still available?
According to rtl-sdr.com, the V4 was discontinued after R828D chips ran out and was replaced in 2026 by the limited-edition V4L. Some resellers may still have V4 stock.
Does a more expensive SDR receive further?
Not necessarily. Range depends first on the antenna and where it sits. A high-end receiver mainly brings better handling of strong signals and a wider visible bandwidth.