The FLEX-6400/6400M is a 100W HF transceiver designed for the shortwave bands from 160 to 10m, including the 6m band. It features two independent receivers, enabling split mode operation and observing other bands and modes during contests. The direct sampling SDR receivers have a sampling rate of 122.8 MHz and a word size of 16 bits, resulting in an excellent RMDR value of 115 dB. Users can enjoy a spectrum width of up to 7 MHz, allowing simultaneous observation of multiple amateur radio bands. The receiver frequency range is from 30 kHz to 54 MHz, while the transmitter is limited to amateur radio bands. The transceiver also offers a 10 MHz reference clock input for high requirements and a transverter output for VHF bands.

The FLEX-6400/FLEX-6400M transmitter provides 100W transmit power (PEP, 25W AM) with suppression of unwanted by-products better than 60dBc. The transverter output can be adjusted from 0 to +10 dBm. An optional antenna tuner is available to correct automatically matches up to 3:1 SWR. 

Flex Radio transceivers prioritize easy-to-handle remote control. The FLEX-6400 can be operated with any Windows PC, iPhone, or iPad. The Maestro console can access the transceiver via WLAN or wired Ethernet. The 'SmartSDR' software in version 3 introduces the 'multiFlex' function, allowing simultaneous use of a transceiver with a second user. This enables easy 'Multi-Op/Single-Radio' operation over long distances.

The FLEX-6400M model offers all the features of the FLEX-6400 and includes a front panel. The control panel features a brilliant touch screen with a resolution of 1920x1200 pixels. Traditional controls are strategically placed for easy and straightforward cooperation, even in hectic contest situations. Remote control of Flex Radio transceivers is possible through SmartSDR software on Windows PC, SmartSDR for IOS on iPhone or iPad, and the Maestro console. Remote operation can be done via the local network or the Internet, allowing users to work from anywhere on DX stations. The latest version of SmartSDR software enables simultaneous operation by two remote operators using a mix of devices.

The shipment includes the Flex Radio 6400 or 6400M, FHM-2 Microphone, DC Cable Power pole, and RJ-45 Ethernet Cable.