Frequencyn/a (SO2R controller/interface)
Bandsn/a
PowerAn all-in-one two-radio (SO2R) USB controller/interface for CW/SSB/AM/FM and digital modes. No RF; it switches audio, keying, PTT and CAT between two transceivers.
Modesn/a
Connectors
radiosCAT/CI-V for two radios
usbsingle USB to the PC
ioPTT/LNA/PA keying, audio in/out, paddle/mic/headset
power reqUSB / 13.8 V DC.
All-in-one two-radio (SO2R) USB controller for all modes Rig control for two radios (Elecraft/Icom/JRC/Kenwood/Ten-Tec/Yaesu) Second-generation WinKey CW keyer built in Dual-codec sound system with sophisticated audio routing Shares one mic/paddle/headset between two radios USB Device Router provides virtual COM ports to logging software
Strengths

The reference SO2R box; superb audio routing; built-in keyer and dual codecs; integrates with all major loggers.

Weaknesses

Expensive; deep configuration; overkill for single-radio operating.

Verdict

The benchmark SO2R controller - the MK2R+ ties two radios, their audio, keying and CAT into one contest-grade operating position.

The microHAM MK2R+ is an all-in-one two-radio (SO2R) USB controller for CW, SSB and digital modes: rig control for two transceivers, a built-in WinKey keyer, a dual-codec sound system and sophisticated audio routing that lets one mic, paddle and headset serve both radios. It integrates with all major logging software.

Compare the simpler DX Doubler, or the single-radio microKEYER II.