Direct sampling HF transceiver


The SunSDR2 QRP is the HF transceiver with 5W output power and a wide range of capabilities. Thanks to the constantly improving ExpertSDR2 software and advantages of the direct sampling the SunSDR2 QRP can solve any given task for a reasonable price. The SunSDR2 QRP can be used either locally via the LAN interface or remotely using the Expert Remote system, it gives you flexibility in arranging your working place as never before.

Main features

  • Immense functionality for a reasonable price
    Designing each our device, we try to reach the best balance between the price and functionality
  • Full support of the ExpertSDR2 software
    Continuously growing and improving ExpertSDR2 software is 100% compatible with the SunSDR2 QRP and will continue to support it for many years to come, for free!
  • Remote control operation with Expert Remote system
    You may set the SunSDR2 QRP in your remote shack or village, away from the city noises, to get the best noise floor, and use it from your bedroom in comfort
  • External control connector
    Connect up to 8 external devices to 8 powerful keys with open collectors, such as PAs, external filters, rotate antenna devices etc.
  • No need for an external soundcard
    The SunSDR2 QRP does not require an external sound card and audio cables, just plug your headphones in the transceiver and listen to the air
  • 16-bit ADC at 122.88 MHz
    The SunSDR2 QRP has the best ADC in its price range which provides 124 dB BDR
  • Sample rates: 48-384 kHz
    At the same time, you can use a 60 MHz wide bandscope + 2 software RXs, each has a SubRX
  • Special mode for 768 kHz or 960 kHz sample rate, only for 1 RX + bandscope at the same time
  • Supports 4M band only for RX in the 2nd Nyquist zone


Application field

  • HAM amateur HF transceiver
  • Remote operation just for fun and for contests
  • Spectrum analyzer with the wide bandscope up to 60MHz
  • Record IQ files and listen to them afterward


Minimum PC specs

  • CPU Intel Core i3 or higher
  • 4 GB RAM
  • Video card with 512 Mb RAM and OpenGL 1.5 support
  • Local network connector 100 Mbps or 1 Gbps
  • The ExpertSDR2 works with Windows 7-10, OS Linux Ubuntu x64 and macOS 10.12 and newer


Architecture description

Block Diagram SunSDR2 QRP

 Basic configuration:

  • Transceiver SunSDR2 QRP
  • LAN-cable (1.8m)
  • Power supply cable (2m)
  • RF Cable  Mini UHF — HF (PL259) 1Ft (0.3m 1 pc.)


General coverage receiver in HF, MHz 0.1...55
Frequency coverage in HF in TX mode, MHz All amateur frequencies
Sensitivity, uV 0,1
Maximum output power in HF, W 7
Blocking Dynamic Range in HF mode (BDR), dB 124
Dynamic Range over IMD3 (2 kHz), dB 110
Reciprocal Mixing Dynamic Range (2 kHz), dB 107
RF ADC clock frequency, MHz 122.88
RF ADC resolution, bit 16
RF DAC clock frequency, MHz 122.88
RF DAC resolution, bit 14
TX IMD3, dB >30
Local oscillator's stability, ppm +/- 2.5
Supply voltage range for TX mode, V +10...15
Supply voltage range for RX mode, V +7...15
Recommended supply voltage, V +12
Maximum consumption current, А 3
Built-in audio codec resolution, bit 24
Operating temperature, ºC 0...+75
Dimensions, mm 185х106х45
Weight, kg 0,5

* More modes can be supported via external software

Specifications are subject to change without notice or obligation and specifications are only guaranteed within the amateur radio bands.


pdf Terms of the product's warranty

pdf ExpertSDR2 User Manual v1.1
The new version of the User Manual for the SunSDR2 QRP transceiver - 11.07.2018

User Manual Addendum version 5.1, by Erik EI4KF

October 2018

pdf Using the transceiver for SO2V operation

pdf Using the transceiver for SO2V operation with SDC

Both diagrams can be used for creating two working places with a single SunSDR2 QRP transceiver.



Warning! Software for each device is different! Double-check your device before downloading!


installer ExpertSDR2 v.1.2.0_SunSDR2 QRP

installer ExpertSDR2 x64 v.1.2.0_SunSDR2 QRP

Firmware v. 6.0 dd: 09-06-2018

Published on 09-06-2018


pdf ExpertSDR2 1.2.0 final_Release_Notes

pdf ExpertSDR2 1.2 RC7_Release_Notes

pdf ExpertSDR2 1.2 RC6_Release_Notes

pdf ExpertSDR2 1.2 RC5_Release_Notes

pdf ExpertSDR2 1.2 RC3_Release_Notes

pdf ExpertSDR2 1.2 RC2_Release_Notes

pdf ExpertSDR2 1.2 RC_Release_Notes

pdf ExpertSDR2 1.2 beta_6_Release_Notes

pdf ExpertSDR2 1.2 beta_4_Release_Notes

pdf ExpertSDR2 1.2 beta_3_Release_Notes

pdf ExpertSDR2 1.2 beta_2_Release_Notes



To use the ExpertSDR2 software, please install the Visual Studio Redistributable 2017 either from the ExpertSDR2 installer or from the official Microsoft website:


  Linux x64 (created by Ubuntu 16.04)

installer ExpertSDR2 v.1.2.0

Firmware v. 6.0 dd: 09-06-2018

Published on 09-06-2018


mac oc x macOS

installer ExpertSDR2 v.1.2.0

Firmware v. 6.0 dd: 09-06-2018

Published on 09-06-2018


ExpertSDR2 works on macOS 10.12 Sierra (earlier versions weren't tested).