The ExpertSDR2 software is the property of the Expert Electronics company, we've been developing it since 2011, thus it embraced a lot of ideas and real user experience for a long period of time. Thanks to the incredible community of HAMs, their feedback, and suggestions we were able to improve the ExpertSDR2 to the point when our customers can honestly say - it is the most versatile and advanced software on the market today.

On the picture below you can see the main window of the ExpertSDR2 1.0.0 for the SunSDR2 transceiver.
ESDR2 1.0.0

Since its official release, we've added numerous features and significantly improved overall software functionality. The most notable additions are:

- Customizable Spectrum Scope and Waterfall

- Several COM-ports to control CW-keyer from loggers and special software for CW

- Direct control of the CW Skimmer via telnet protocol, additional RX IQ output into CW Skimmer via VAC and show received spots from CW Skimmer on the panorama

- Line output to record your on-air activity

- Features tab, which allows you to auto-launch third-party software along with the launch of the ExpertSDR2

- Shortcuts tab, allows you to set a lot of shortcuts for almost any function in the ExpertSDR2

- OmniRig exchange protocol

- MB1 GUI (special GUI for the MB1 internal display)

- Waterfall cleansing algorithm

- ExpertSync software, it allows you to synchronize all Expert Electronics devices between each other

- Seamless compatibility with the E-Coder panel

- RX ANT button, which in the 1.2 version became the part of the Antenna Switch

- DSE (Digital Surround Effect) for CW. Provides a spatial orientation in stereophones, stations from lower frequencies are louder in the left channel, stations from higher frequencies are louder in the right channel. The signal in the filter's center is equally heard in both channels of stereo phones.

- APF (Analog Peak Filter) for SSB and CW. Provides a more comfortable listening of the CW signals by amplifying the CW signal in the center of the receive filter (triangle filter's AFC (amplitude-frequency characteristic) in the filter bandpass).

- Countless minor features, improvements, tweaks, and optimizations

On the picture below you can see the software main window for the MB1 transceiver.
ESDR2 screenshot


1) Antenna switch for SunSDR2/PRO and MB1. It works the same way for both devices: for each frequency band, antenna switch saves its own antenna input and output.

When two software receivers are active (RX1 and RX2), antenna input is the same for both receivers (because devices have one ADC), but the transceiver's antenna output may differ if software receivers work on different frequency bands.
For a thorough description of the Antenna switch please see the User Manual.

Antenna Switch


2) 4K display mode, it allows you to use a 4K monitor to work with the ExpertSDR2.


3) Professional TX processing module for all our transceivers. The module consists of the following features:

- DC block to effectively remove the Time constant in mic signal,

- Parametric Filters with 5 independent filters of 7 types,

- Noise Gate to reduce noise in pauses,

- Compressor to reduce the dynamic range of the audio signal,

- Limiter to avoid overload (clipping) and suppression of short-term level peaks, 

Parametric Equalizer with 8 Peaking filters, Low Shelf and High Shelf on the sides,

AGC to keep the constant volume level of the Mic signal,

Clipper to reduce signals peak-factor and increase overall power while distorting the signal,

- This module has its own Profile system, independent from the Global Profile.


For a thorough description of the TX processing module please see the User Manual. On the picture below you can see the Equalizer module.

PROC module


4) ExeprtSDR2 was ported to the Qt5 libraries. To 99% of people, it won't mean anything. In reality, it allowed us to drastically optimize the software operation for each supported OS and to add new features, such as:

- TCI - Transceiver Control Interface was developed by Expert Electronics company, for simple and still advanced connection between the ExpertSDR2 and third-party software. TCI has all required control commands similar to CAT system, but even more, it can transfer IQ-streams from the ExpertSDR2 to clients (third-party software such as signal Skimmers, etc) via local network and the Internet, CW macroses and Audio In/Out streams for digital modes. TCI is the universal multi-client interface (you can connect it to radio Loggers, Skimmers, PAs, Ant.switches, etc. at the same time). It was developed as an open protocol to use with multi-brand transceivers, which support one, two or multi receivers/transmitters. This is a game-changer for the SDR radio!
It is an open-source protocol, we've discussed using it with hardware and accessory developers. For example, Band Pass Filters unit with LAN interface can get information about radiofrequency via LAN and can switch filters, the same applies to antenna switches and PAs and so on.

Connection process with TCI is very easy, someday in the future, you won't believe you lived without it for so long!
Several software developers are already working on the implementation of TCI in their software, we will try to get TCI into all HAM software. - Link to the list of files with the description of the interface in English and Russian and source code of the demo-client software with TCI support.

- macOS X support
- New visual effects and animations are coming


5) The new ExpertSDR2 x64 version for OS Windows x64, allowed to lower CPU load by approximately 20%.

On the picture below you can see the software main window for the SunSDR2 PRO transceiver.
ESDR2 130

1) New button Device options for quick access to hardware settings
Device options
2) New button to call up Volume and Monitor settings, it appears when you squeeze ExpertSDR2 window
3) A switchable compact/classic display of band and mode buttons (compact on the screenshot above). Options-> Display-> Main tab-> Compact band/mode panel checkbox
4) Switchable spectrum slopes to disable unused area (switched off on the screenshot above). Options-> Display-> Spectrum tab-> Hide spectrum slopes checkbox
5) TX signal analyzer in TX PROC module, to analyze your own signal. You can monitor your own signal either before (low latency) or after (higher latency) the modulator
TX signal analyzer
6) Phase rotator in TX PROC module
Why do you need a phase rotator? Sound vibrations created by human speech organs are asymmetric by amplitude. They have lots of negative and positive half-waves. It's natural and not a problem in itself, but some voices may be so asymmetric that compressor and limiter (which are controlled by peak or RMS signal level) may rapidly lower their levels because of such asymmetric signal peaks. As a result voice density may drift (vary in real-time), so the voice doesn't sound natural. Phase rotator changes phase ratios in a signal, leaving the AFC as it is (it's not an equalizer). Harmonics are shifted in relation to the main frequency, the signal becomes more symmetrical. Elimination of most asymmetric peaks in the signal lowers the "aggressiveness" level of the compressor influence, thus voice sounds more natural and dense at the same time.
Also, rotator gives you a psychoacoustic effect from amplifying the low frequencies and making your voice sound clearer. It appears because of harmonics time-shift in relation to fundamental frequencies. After the voice is processed with rotator, you hear harmonics and main frequencies at different times. It makes harmonics more prominent to our brain, creating a psychoacoustic effect making a voice clearer.
7) Pre-proc module in TX PROC module, it enriches signal with new harmonics imitating tube preamplifier
8) Using several ColibriNANO on the same PC, you can select the required one from the list
9) CW PITCH setting was added for receivers
10) Automatic detection of ITU band plan
11) VOX On, VOX Off can be assigned to E-Coder panel buttons
12) Opportunity to transfer audio signal via TCI, it allows third-party developers to eliminate VAC, transferring audio signal via TCI
13) New commands in TCI
- for operation with CW macros
- to inform third-party software, that ExpertSDR2 is in focus or not, and control of this parameter
- to control tuning frequency VFO
- enable/disable SQL
- control SQL level
- protocol version, informs which TCI version is used and firmware version (at the moment informs only about TCI version)
- clear all spots
- output power level indication
- TX SWR level indication
- global volume control
- Mute, with an argument for a receiver
- Tune, with arguments on/off
- Drive, to control the output power
- Tune_drive, to control the tune output power
14) From now on you can record IQ-files in HDSDR compatible format

Changes to the current functionality:

1) Mute is disabled if you change the volume

2) BIN algorithm was improved for AM/SAM/DSB/NFM

3) Line Out/Sound Card/VAC modules were updated, the same way we've done it in the ExpertRC 1.3.0

Manual Notch Filter in IQ bandwidth, which is set on a certain frequency

In the middle of the Notch Filter, it completely suppresses the tone signal, but you gotta take into account filters' fronts, as you can see filter width directly influences its quality

Despite wide functionality the ExpertSDR2 currently has, we plan to continue expanding it. Constant improvement and innovation, that is what lies ahead of the ExpertSDR2.
Buying any of our devices, you get the ExpertSDR2 software for free, with all the upcoming updates, which are also absolutely free!


Links to the Download page with the ExpertSDR2 software for each device:

MB1 | SunSDR2 DX | SunSDR2 PRO | SunSDR2 QRP | ColibriDDC | ColibriNANO

Warning! Software for each device is different!

The ExpertSDR2 minimal system requirements:

  • 2 or 4 core CPU Intel Core i3 or Core i5;
  • 8 GB RAM;
  • 40 GB free space on the HDD/SSD for the ExpertSDR2 and accompanied programs;
  • 17' or bigger monitor;
  • video card with OpenGL 1.5 or higher;

The ExpertSDR2 software supports Windows 7-10 32/64 bit, Linux (Ubuntu/Kubuntu 18.04 x64), and macOS 10.14 Mojave and higher.
Warning! The ExpertSDR2 software for Windows requires Visual Studio Redistributable 2017, you may install it either from the ExpertSDR2 installer or from the official Microsoft website.


A development plan for ExpertSDR2 1.3:


Version 1.3.2

New functions:

  • Transverter mode


Version 1.3.3

New functions:

  • ALC


Version 1.3.4

New functions:

  • The 4M band will be supported in software

  • Implementing transmitter protection based on SWR
  • New menu for RX PROC module, settings for all audio processors will be gathered in one menu, will be added display of audio spectrum and time diagram
  • Possibility to assign APF on programmable F1-F10 buttons in MB1
  • An adjustable rotation speed of AF/RF knobs in MB1
  • New commands in TCI:
    - Switch Receiver (E-Coder) - with an argument for a receiver

Changes to the current functionality:

  • A completely new module of the antenna switch, separate settings window for each band
  • Separate window to control EXT.CTRL. and PA keys


Version 1.3.5

New functions:

  • Storing repeater stations for NFM (VHF / UHF)

  • Implementing of the Omni-Rig v2.0 interface (

  • Pressing the Esc button, the transceiver will turn to RX mode

  • Implementing the Receive only mode for all transceivers

  • Improving operation of the NFM modem algorithm with SQL and CTCSS / DTMF

  • Opportunity to change transmitter frequency during transmission, inside one band

Changes to the current functionality:

  • More information fields in the Memory panel module

  • Excessive functions (related to transmission) will be removed from the E-Coder panel for receivers


Version 1.3.6

New functions:

  • A new module of IQ recorder, implemented in ExpertSDR2

  • Automatic fine tuning for CW stations

  • New profile system in the Power correction menu

  • Storing ATU settings in MB1 for antenna connectors

  • Polishing of MB1 GUI


Version 1.3.7

New functions:

  • Control of external tuner with the TUNE button, via EXT.CTRL. keys

  • Adding TCI operation via TCP server, to support Hamlib

  • Adding Morse code on German and Cyrillic in TCI

  • Profiles for DX operation

  • Storing SQL level per band

  • Adjustable delays for CW signal in TX mode (not for monitoring)

  • Separate step setting for RIT and XIT

  • Sync XIT and RIT function

Changes to the current functionality:

  • Default settings for all DSP processors of RX and TX


Version 1.3.8

New functions:

  • Opportunity to display a selected band in the whole bandscope, for example by a double-click of a mouse button

  • Opportunity to correct S-meter (during connection of external preamplifier)

  • Adding a new command to CAT - AI to identify transceiver

  • Noise Cancellation in WFM

  • Adding 9 kHz filter bandwidth for DRM

  • Opportunity to save mic settings per mode, in PROC menu


Development plan may be changed in time