The SunSDR2 DX transceiver is based on the well-known SunSDR2 PRO transceiver with several hardware improvements. It is very compact for a 100W format, has active cooling, and an improved supply system, meaning it’s perfectly suited for DXpeditions. Also, it has a separate connector for an external ATU, thus SunSDR2 DX has all the functionality you got used to in our radios and even more. Improved hardware along with the ExpertSDR2/3 software makes this high-performance SDR transceiver the perfect base station. The evident choice for a true contester!

Hardware improvements in comparison to SunSDR2 PRO:

  • Improved TX IMD3 ~37 dB across all HF bands, with 100W output power
  • Improved TX filters for 160M, 6M and 2M bands
  • HPF for VHF (100 MHz) to eliminate strong out-of-band stations coming from HF
  • LPF for HF (70 MHz) to eliminate strong out-of-band stations coming from VHF
  • New VHF LNA chip - PGA103+
  • New high-performance built-in stereo audio codec 24 bit with 114 dB dynamic range (CS4272)
  • Improved supply system, which leads to less heating and less power consumption
  • Active cooling and improved design of the heatsink
  • Antenna switch supports Predistortion without external devices
  • Firmware based protection algorithms in the PA board
  • Sturdy DIP-type ExtCtrl connector
  • New connectors: external tuner control, GND
  • Improved PCB topology


Main capabilities

  • Independent RX path based on DDC (Direct Down-Conversion) architecture
  • Independent TX path based on DUC (Direct Up-Conversion) architecture
  • Output power: 100W on HF, 80W on 6M and 8W on 2M
  • 2 software RXs + SubRX for each of them (4 slices total) + independent wideband Bandscope up to 80 MHz
  • Remote control operation, using it, you connect PTT and CW-key to the E-Coder panel. Microphone and E-Coder are connected to the remotely set up PC
  • TCI interface for seamless connection with third-party software, the list of software with TCI support
  • Professional TX processing module provides the most advanced tuning capability for voice operation
  • ExtCTRL connector to control external devices with 8 powerful keys with open collector
  • ALC connector for external power amplifiers*
  • Supports use of VHF transverters**
  • An opportunity to use the transceiver as a signal generator via DAC OUT connector (SMA connector)
  • An opportunity to use external filters in the middle of the RF path, using ADC IN and RX OUT (SMA connector)
  • Monitoring delay in CW mode is about 5-6 ms
  • Input for external 10 MHz reference oscillator
  • An opportunity to use the transceiver in SO2V mode
  • Full duplex or half-duplex modes***
  • Antenna switch with 2 HF antenna connectors and separate VHF antenna connector (Mini UHF connectors)
  • Internal power-meter for HF and VHF bands and SWR-meter for HF band
  • Ethernet LAN interface provides a fast and reliable connection to PC

* ** *** These functions are supported by the transceiver's hardware, but is not implemented in the ExpertSDR2 software. They will be supported in the future ExpertSDR2 software releases.


Architecture description

Block diagram SunSDR2DX


SunSDR2 DX complete set

  • Transceiver SunSDR2 DX
  • External fan, size 140 x 140 mm
  • LAN-cable for connection to a local network (1.8m)
  • Power cable for connection to a power supply (2m)
  • Audio-adapters JACK 6.3mm to JACK 3.5mm (2 pcs.)
  • RF Cable Mini UHF — HF PL259 1Ft (0.3m 1 pc.)


Additional accessories:



RF ADC, bit @ MHz 16 @ 160
ADC type LTC2209
RX Frequency range, MHz 0.1...65; 95...155
Independent software receivers 2 + 2 SubRX
Sample rate, kHz @ bit 39; 78; 156; 312 @ 24
Bandscope, MHz 80
RX HF filters, MHz (LPF: 65 or 9 x BPF) + constant LPF: 70
RX VHF filters, MHz (WideRX: 95-155 or SAW filter for 2M: 144-148) + constant HPF: 100
BDR on HF, dB 130
BDR on VHF, dB 129
Sensitivity, uV 0.2
DR IMD3, dB 110
RMDR, dB 119
ATT/Preamp, dB -20; -10; 0; +10
VHF LNA, dB 27
RF DAC, bit @ MHz 14 @ 640
TX Frequency range, M All amateur bands 160-6; 2
Output power on HF, W 100
Output power on 6M, W up to 80*
Output power on VHF, W 7 (up to 8)
TX IMD3 on HF, dB 37 on HF / 30 on VHF
Local oscillator TCXO, MHz +/- ppm 20 +/- 0.5
External 10 MHz oscillator input +
Built-in audio codec, bit 24
RF input/output 2HF, 1VHF (Mini_UHF)
PC interface LAN 100 Mbit
DC voltage range in RX/TX, V 8...14.8 / 10...14.8
Recommended DC voltage, V 13.8
Current consumption RX/TX, A 1.2 / 24
Power consumption RX/TX, W 16.5 / 330
Operating temperature, °C/°F 0...+50/ +32...+122
Dimensions L x W x H, cm/inches 18.5 x 16.5 x 10.5/ 7.48 x 6.69 x 3.14
Weight, kg/lbs 1.8/ 3.96

* 80W until 53MHz, then output power is slightly decreased.
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 SunSDR2 PRO Getting Started
pdf Empezando (Getting Started in Spanish) 

pdf "Setting up SunSDR2 PRO for DUMMIES" by Pete Parisetti, MM0TWX
pdf El primer procedimiento 11-09-19

pdf User Manual v.1.3.2 06-07-22
pdf Manual de Usuario v1.3.2 22-09-20

ATU connector pin-out

pdf User Manual Addendum, by Erik EI4KF

pdf Adenda del Manual del Usuario version 6.12 12-05-21

Setup instructions for WSJT-X, ExpertSDR2, and MacLoggerDX


Useful diagrams

pdf ExtCtrl to SPE Expert PAs connection diagram

pdf ExtCtrl to ACOM PAs connection diagram

pdf ExtCtrl to EB104 connection diagram
Recommended by EB104 manufacturer

pdf ExtCtrl to EB104 connection diagram with relay

pdf SO2V operation

pdf SO2V operation with SDC
Both diagrams can be used for creating two working places with a single SunSDR2 PRO/DX transceiver.

pdf Connecting an external PA, fan, relay, etc. to the SunSD2 PRO/DX
In this document, you can find information about how to connect the SunSDR2 PRO/DX to an external PA, fan, or relay to control the external BPF, antenna switch, etc.

pdf Control cable schematic for external PA VL-1000 (Yaesu)
This schematic allows you to assemble your own control cable for PA VL-1000 by Yaesu. With this cable, you control PA's bands and RX/TX mode. This cable might be used for control of other devices, which works with 4-contact control protocol by Yaesu, i.e. PAs, antenna switches, etc.



Warning! Software is device-specific! Don't mix software with unsuitable hardware, it may lead to issues that are not covered by warranty!


installer ExpertSDR2 v.1.3.1 Update11_SunSDR2_DX
installer ExpertSDR2 x64 v.1.3.1 Update11_SunSDR2_DX
SDR firmware v. 72 dd: Fall 2021
PA firmware v. 12 dd: July 2020
Published on 12-10-2020
pdf ExpertSDR2 1.3.1_Release_Notes
ExpertSDR2 1.3.1_Update 11_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

installer ExpertSDR2 v.1.3.1 Update11
Published on 13-10-2021

ExpertSDR2 tested on Ubuntu 20.04 x64.

mac oc x macOS

installer ExpertSDR2 v.1.3.1 Update11
Published on 14-10-2021

ExpertSDR2 was tested on the latest macOS release. ExpertSDR2 might crash during the closing, but it doesn't affect software operation at all.

Articles and Reviews

Expert Remote System (ERS) reviewed by Werner Schnorrenberg (DC4KU) (July 2022)
English version / German version
Published in Funkamateur

Output voltage spikes investigation, by Ivan De Cesaris IZ0JNY/HB9ETO (December 2021)

Review published in CQ DL 1/2022 and 2/2022, by Werner Schnorrenberg (DC4KU) (November 2021)
German version / English version review page

AAT-100 tuner review in Radioamater, by Pavel Misek (OK7PM(April 2021)
In Czech

Review of the SunSDR2 PRO and SunSDR2 DX by Graziano Roccon (IW2NOY) (March 2020)

Review in Radioamater, by Pavel Misek, OK7PM (January/February 2020)
Part 1 / Part 2
In Czech

ExpertRemote system reviewed by Werner Schnorrenberg (DC4KU) (November 2019)
Published in Funkamateur 3-2020