The FLEX-8400M offers the latest direct sampling SDR technology with a high-resolution display and ergonomic controls.

Supporting Adaptive Predistortion

The FLEX-8400M integrates all FLEX-8400 capabilities with a stunning 8-inch 1920×1200 IPS WUXGA touchscreen display and ergonomic controls to deliver a high-performance Software Defined Radio (SDR) with a traditional radio interface.

It delivers unmatched band awareness from an integrated display while providing an external connection to monitor compatible 1900×1200 resolution on a monitor for maximum spectral visibility.

Influenced by top contest/DX operators, its symmetrical and independent dual VFO controls are strategically placed to provide maximum productivity for all types of operation. It’s completely self-contained so just plug it in and operate – no PC, network or learning curve required.

With a PC, laptop, or Mac client you can utilize up to two 7 MHz spectrum/waterfall displays and independent receivers to revolutionize your view of the bands. Its two receivers can be placed simultaneously on any band and mode with instant QSY between VFOs. Digital mode operation is a dream with no sound cards, cables, or boxes needed.

FlexRadio’s industry-leading SmartSDRTM software offers compatibility across the entire FLEX-8000 Signature Series family to deliver continuous leveraged software enhancement. And you can use the latest SmartLinkTM technology to access your radio virtually anywhere from any SmartSDRTM compatible client with only a login and password – even your iPhone.

*Mac OSX SmartSDR and iOS SmartSDR clients are provided by third-party vendors

  • 100W PEP HF-6m operation
  • All modes/all bands
  • Integrated Remote Operation with Maestro, PC/Laptop, Mac, IPad® or iPhone®
  • 2 Independent Band / Mode Receivers
  • Full Duplex Cross-Band Operation
  • Transverter Port
  • Receive-Only Antenna Port
  • Direct Sampling SDR 122.88Msps – 16 bit
  • 115 dB 2kHz RMDR
  • >155 dB Dynamic Range
  • 10 MHz Reference Input
  • Optional Integrated Antenna Tuner, Range 3:1 SWR
  • Optional GPSDO for ultra high frequency precision and accuracy
  • Optional MARS/CAP/SHARES TX Expansion Module

All-in-One SDR includes all the features of the FLEX-8400 plus

  • Spectacular 8-inch, 1920 x 1200 IPS Integrated Display
  • Touch Tune, Zoom, Pan Controls at Your Fingertips
  • Ergonomically Optimized Controls with Full Dual VFP
  • Up to 7MHz Spectrum/Waterfall Bandwidth
  • Real-time Spectrum / Waterfall
  • External Display Output – Full 1920 x 1200 Resolution
  • Internal Speaker


  • Weight: 256 oz
  • Width: 18 in
  • Depth: 19 in
  • Height: 12 in


  • Independent Band/Mode Receivers (Max): 2
  • ½ kHz Reciprocal Mixing Dynamic Range (RMDR): 110/115 dB
  • ADC Bits/Sampling Rate: 16/122.88 Msps
  • Frequency Coverage: 30 kHz-54 MHz
  • Amateur Band Preselectors: 3rd Order
  • Cable-less Digital Audio (DAX/DAX IQ) Channels: 2/2
  • Receive Only Ports (Base/Including XVTR Port): ½
  • Full Duplex RX/TX Operation

Spectrum / Waterfall

  • Integrated Touch Panel Display Size Diagonal: 8-inch (8400M)
  • Integrated Display Resolution: 1920 x 1200
  • External Display Resolution/Connection: 1920×1200 / HDMI (8400M)
  • Spectrum / Waterfall Displays (Max): 2
  • Spectrum /Waterfall BW (Min/Max): 5 kHz to 7 MHz
  • Spectrum Dynamic Range (Max Zoom In): >145 dB
  • Spectrum Resolution Bandwidth (Min): 5.58 Hz/px


  • 160m-6m Transmitter Output: 1-100W (25W AM)
  • Harmonic Suppression (Typ): <60 dBc
  • Transverter Ports: 1
  • Transverter Frequency Coverage/Power: 100kHz – 54 MHz/0 to +10 dBm
  • Optional Integrated Automatic Antenna Tuner Range: 3:1 SWR
  • Optional Continuous MARS/CAP Coverage with Extended Transmit Filter


  • Integrated Remote Operation (SmartLink)
  • Maestro, PC, Mac, iPhone® and iPad® Client Options
  • Frequency Stability (0⁰C – 50⁰C) 0.5ppm (TCXO)
  • Optional GPS Disciplined Oscillator (5 x 10-12 Over 24 Hours)
  • External 10MHz Reference Input
  • Power Supply Requirements 13.8 VDC +/- 15% (14 VDC Nominal)
  • Dimensions 6.74”H (17.1 cm) x 14”W (35.6 cm) x 13.25”D (33.7 cm)

1. RTTY and other digital modes use 3rd party software over DAX channels.

Simply Beautiful

  • No PC required to operate the FLEX-8400M
  • 8 inch 1920 x 1200 IPS Display
  • Up to two independent receivers
  • Up to two 7MHz spectrum displays
  • Optimized workflow
  • Ergonomically spaced / single-function controls

Plug & Play Remote 2

  • No complex setup required
  • Operate anywhere, any time
  • Use a Maestro, Mac, iPad, iPhone or Laptop
  • Across the country or across the world
  • Anywhere, Anytime, From Any of These Devices:
    • With SmartLink and a FLEX-8400M, you can operate your radio from almost anywhere! Just take an iPhone, iPad, Laptop, or Maestro with you and instantly connect to your radio with virtually no setup required.

Best in Class Performance

  • 115 db RMDR
  • No listening fatigue
  • Ultra-low phase noise
  • Full Break-in QSK CW
  • Brick Wall Filters
  • Stunning transmit audio

Backed by an Amazing Suite of Software

  • SmartSDR for the M Model Radio
  • SmartSDR for Windows
  • SmartSDR for Mac3
  • SmartSDR for iOS3
  • SmartSDR CAT
  • DAX

1 – A PC is required for use of 3rd party software such as loggers and digital mode programs.
2 – SmartLink Remote requires SmartSDR v2.x license or higher. Requires and Internet connection.
3 – SmartSDR for Mac and SmartSDR for iOS are optional, 3rd party software for pay options.

FlexRadio does not charge your credit card until your order ships, but we do pre-authorize the full purchase price at the time you place your on-line order. If you choose to use PayPal as your payment method, your account will be charged immediately.

Due to the price class of a FLEX-8400M, your order may exceed your credit card’s daily transaction limit resulting in your order not being completed. In these cases, you may either contact your credit card company and negotiate a different daily purchase limit -OR- you can call the FlexRadio Sales department at 512-535-4713 ext 1 to place your order over the phone where we will not pre-authorize order payment until time of shipment.

Resources for FLEX-8400M Signature Series SDR Transceiver