Airspy HF+ Discovery SDR Receiver

Overview

The Airspy HF+ Discovery builds on the field-proven Airspy HF+ platform with added preselectors, refined filtering, and a new DSP core for improved gain distribution and real-time optimization. The result is a receiver that digs deeper into the noise while maintaining excellent linearity in crowded RF environments. Its architecture combines high dynamic range sigma-delta ADC technology, passive mixers with polyphase harmonic rejection, and band-tracking preselectors to help suppress unwanted signals and preserve usable dynamic range. For SWL, AM DX, FM broadcast DX, amateur radio monitoring, telemetry, spectrum analysis, and SIGINT-style receive applications, the HF+ Discovery delivers performance far beyond what its size suggests.

Key Features

• Coverage from 0.5 kHz to 31 MHz and 64 MHz to 260 MHz
• High dynamic range front end with strong blocker resistance
• HF sensitivity down to -140 dBm minimum discernible signal at 500 Hz bandwidth
• VHF sensitivity down to -141.5 dBm in the FM broadcast band and -141.0 dBm in the VHF aviation band
• Blocking dynamic range up to 110 dB on HF
• High-performance preselectors for HF, FM broadcast, and VHF ranges
• Polyphase tracking filters for close-range interference suppression
• 18-bit embedded digital down converter with up to 22-bit resolution at 3 kHz channel bandwidth
• Up to 660 kHz alias- and image-free output for 768 ksps IQ
• Very low phase-noise 0.5 ppm clock with 1 ppb frequency adjustment capability
• Plug-and-play operation with broad software support
• Ultra-compact enclosure measuring 45 x 60 x 10 mm (1.77 x 2.36 x 0.39 in)

Typical Applications

• HF and VHF amateur radio monitoring
• Shortwave listening and broadcast DXing
• AM, FM, and TV DX reception
• Spectrum analysis and signal hunting
• Telemetry and utility signal monitoring
• SIGINT/COMINT receive applications
• Remote SDR deployments with SpyServer

Specifications

Architecture

State of the Art SDR streaming technology!

We concentrated state of the art DSP and networking techniques into our SpyServer software to allow multiple users to stream high quality IQ data from the same receiver at the same time. No compromises in the quality were made like it is usually done in Web SDR interfaces. You get actual IQ data you can process with your plugins and extract the last bit of information out of it.
The server software is highly scalable and can run on computers as small as the $7 Orange Pi Zero to top end 64bit servers with multiple cores/cpus, including the popular Raspberry Pi series.

Why choose the Airspy HF+ Discovery?

• Excellent weak-signal performance with outstanding sensitivity and low internal noise
• Strong-signal resilience that helps maintain clean reception in crowded RF environments
• Broad software compatibility with popular SDR platforms including SDR#, SDR-Console, GQRX, HDSDR and more
• A proven design recognized by WRTH for delivering exceptional value in a compact, affordable SDR receiver

User Endorsements

The Airspy HF+ Discovery received the WRTH 2020 Best Value SDR award, with reviewers highlighting its combination of performance, versatility, and value. Independent reviewers have also praised it for delivering performance well above its price class and for being easy to use while still satisfying demanding listeners.

What’s included – In the Box

• Airspy HF+ Discovery receiver
• USB connection for power and data

Note: antenna, coaxial adapters, and SDR software are typically supplied separately unless otherwise stated in the product package.

Performance notes / setup guidance

For best results, pair the Airspy HF+ Discovery with a well-matched external antenna and quality coaxial feed line. In high-signal environments, use the built-in AGC intelligently and avoid unnecessary gain to preserve dynamic range. Airspy recommends adjusting attenuation so the noise floor remains around -100 dBFS when operating manually. For remote monitoring, the receiver also works well with SpyServer on compact single-board computers and low-power network hosts. This makes it an excellent option for fixed receive posts, remote DX stations, and shared SDR access over a local network or the internet.

If you want a compact SDR receiver that punches far above its size and price, the Airspy HF+ Discovery is one of the smartest upgrades you can make for serious HF and VHF listening. Add it to your station and experience cleaner reception, stronger weak-signal results, and a more capable SDR workflow from day one.