Small receiver

for great experts


A compact ColibriDDC receiver was designed to work on HF band 0.09 to 60 MHz, for better performance you can add the internal BPF-module (160-10M bands). With the help of external filters, ColibriDDC can effectively operate on frequencies up to 800 MHz. LAN interface allows you to use the receiver remotely via LAN cable and to connect several receivers to one PC at the same time, for various projects. Also, you can hook up the receiver with the RaspberryPi3 (with installed ExpertRS software) and use it from any place on the Planet, you just have to have a reliable internet connection.

Note! The basic version of the receiver doesn't include the BPF-module.


Main features and capabilities of the receiver

  • RX path based on DDC (Direct Down-Conversion) architecture

  • ExpertRemote system provides full remote control of the receiver

  • 2 software receivers (each up to 312 kHz) + SubRX for each of them (4 slices total) + independent wideband Bandscope up to 62.5 MHz

  • ExtCTRL connector to control external devices with 7 powerful keys with open collector

  • 100 Mbps Ethernet LAN interface provides fast and reliable connection to PC

  • TCI interface for seamless connection with third-party software like SDC (with its own Skimmer), LogHX, SWISSLOG and RUMlog, more are coming

  • Record IQ channel with the bandwidth up to 312 kHz

  • Receiving in undersampling mode up to 800 MHz (requires external BPF)

  • High-quality 24-bit audio–DAC installed for the smallest signal delays

  • Low power consumption, 5V 0.64A

  • External reference generator input 10 MHz

  • Small size W 65 x H 26 x L 125 mm


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.


Receiver's block diagram

  • REF – connector to connect external 10 MHz generator
  • PLL – ADC clock frequency synthesizer
  • ATT – attenuator
  • MCU – microcontroller unit
  • Ant – connector to connect the HF band antenna
  • TCXO – inbuilt temperature compensated crystal oscillator
  • ADC – high-speed analog-digital converter
  • DAC – audio digital-analog converter
  • EXT CTRL - connector for controlling the external devices
  • LPF – input low-frequency filter (disabling)
  • FPGA - field programmable gate array
  • LAN – local network connector
  • PHONES – jack for connecting headphones
  • Front – front panel
  • Rear – rear panel


Basic configuration: 

  • ColibriDDC Receiver
  • Power source 5V 2A
  • Adapter SMA - PL259 (UHF)
  • LAN – cable

Additional accessories:


Receiving bandwidth, MHz 0.01 - 60 (0.01-62.5)
Receiving bandwidth in all Nyquist zones, MHz 0.01– 800
Spectrum scope bandwidth (up to), MHz 62.5
Amount of independent receiving channels 2
Sensitivity, uV 0.3
Blocking Dynamic Range (BDR), dB 110
IMD3 Dynamic Range, dB 90
Image channel suppression, dB >110
Supply voltage range, V 4.5...5.5
Maximum consumption current, A 0.64
RF ADC clock frequency, MHz 125
RF ADC resolution, bit 14
Local oscillator stability, ppm +/- 0.5
Built-in attenuator, dB 0, -20
Built-in audio DAC resolution, bit 24
Dimensions W x H x L, mm 64x24x112
Weight, kg 0.3


* 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.


Optional BPF-kit board with HF octave band filters:

160M: 1.73-2.6 MHz
80M: 2.6-4.3 MHz
60M: 4.3-6.5 MHz
40M: 6.5-7.9 MHz
30M: 7.9-13 MHz
20M: 13-15.9 MHz
17-15M: 15.9-21.0 MHz
12-10M: 21.0-30 MHz
ATT -20 dB
Preamp +10 dB


BPF-kit should be installed inside the receiver's case, with a set of simple manipulations.



pdf Terms of the product's warranty

pdf User Manual v1.2

This manual will help either new or experienced users, it describes the hardware of the receiver and explains how to operate it with the ExpertSDR2 software. 11.07.2018.

User Manual Addendum version 5.3, by Erik EI4KF
January 2019

Setup instructions for WSJT-X, ExpertSDR2 and MacLoggerDX

Connecting Elecraft K3, N1MM+ and ColibriDDC receiver via LAN or Internet

pdf Connecting the ColibriDDC to the CW SkimmerServer

Instruction for the CW SkimmerServer 16/01/2017

pdf Operating the ColibriDDC receiver with a third party software (HDSDR, SDR#)

Instruction for the ExtIO library 16/01/2017

pdf ExpertSDR2 and CW Skimmer

This guide describes how to setup ExpertSDR2 for use with one or two CW Skimmers.



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

You cannot use ExpertSDR2 for ColibriNANO with ColibriDDC and vice versa!


installer ExpertSDR2 v.1.3.0 Beta3_ColibriDDC
installer ExpertSDR2 x64 v.1.3.0 Beta3_ColibriDDC
Firmware v. 6
Published on 07-06-2019
pdf ExpertSDR2 1.3.0 Beta3_Release_Notes
pdf ExpertSDR2 1.3.0 Beta2_Release_Notes

pdf ExpertSDR2 1.3.0 Beta1_Release_Notes

pdf ExpertSDR2 1.3.0 Alpha2_Release_Notes
pdf ExpertSDR2 1.3.0 Alpha1_Release_Notes


installer ExpertSDR2 x64 v.1.2.0_ColibriDDC
Firmware v. 6
Published on 30-11-2018

installer ExpertSDR2 v.1.1.3_ColibriDDC

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


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



Library for work with CW SkimmerServer software

zip iconColibriDDC_SkimSrv  


Library ExtIO for work with the third party software

zip iconExtIO_ColibriDDC

  Linux x64

installer ExpertSDR2 v.1.3.0 Beta3
Firmware v. 6
Published on 07-06-2019


installer ExpertSDR2 v.1.2.0
Firmware v. 6
Published on 03-12-2018

ExpertSDR2 tested on Ubuntu 18.04 x64.

mac oc x macOS

installer ExpertSDR2 v.1.3.0 Beta3
Firmware v. 6
Published on 07-06-2019


installer ExpertSDR2 v.1.2.0
Firmware v. 6
Published on 03-12-2018

ExpertSDR2 works on macOS Mojave.