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

1. 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
2. APF can be assigned to the multifunctional MB1 buttons (F1-F10)
3. Optimized software Start algorithm for MB1, SunSDR2 PRO, and SunSDR2 QRP
4. VAC settings can be saved in global Profiles
5. You can transfer PTT signal from the E-Coder panel via TCI or COM-port

PROC menu - fine adjustments by Vasily Vasilev (RN6LHF).
How to make fine adjustments of the PROC menu and achieve high-quality sound in TX mode.

SunSDR2 in the FT8 mode by Vasily Vasilev (RN6LHF).
How to connect ExpertSDR2+JTDX+LogHX software.

How to install ExpertSDR2 and SDC on Linux Kubuntu 20.04 by Enzo Stefanazzi (IW7DMH).

Explaining Noise Reduction, Noise Blanker, APF (Audio Peak Filter) and RF Gain by Rick Langford (N8SDR).

Buying any of our devices, you get the ExpertSDR2 software for free.

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

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

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


Minimal system requirements:

  • Windows 10 x64 or later versions, Linux Ubuntu 20.04 x64 and the latest patches of versions 11 (BigSur)/ 12 (Monterey) of macOS
  • 4 core CPU Intel Core i3 or Core i5
  • 8 GB RAM
  • Video card with support of DirectX11 or 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.