FlexRadio FLEX-8400M firmware v4.1.3

Page 1 | Copyright 2025 FlexRadio, Inc. | SmartSDR v4.1.3 Release Notes | SmartSDR+ v4.1.3 Release Notes Version Release Date Release Theme/Title 4.1.3 2025-12-03 Aurora Support and SmartSDR+ v4.0.1 Feature Activation SmartSDR Basic™ and SmartSDR+™ v4.1.3 is a software and firmware release for Aurora™, FLEX-8000™, and FLEX-6000™ series of software defined radios (SDRs), and the Maestro™.

This version supersedes all previous versions of SmartSDR.

Description of SmartSDR Basic, SmartSDR+, and SmartSDR+ Early Access Feature License Tiers: SmartSDR v4 Basic is av​ailable free of charge and includes all bug fixes and select minor feature enhancements for all radio models.

We strongly encourage all customers to upgrade to SmartSDR v4.

If you are currently running SmartSDR v2 and upgrade to SmartSDR v4 Basic, you will receive all prior bug fixes and minor enhancements from all previous versions.

However, please note that multiFlex, the major feature introduced in SmartSDR v3, is not included in SmartSDR v4 Basic for radios licensed for SmartSDR v2.

For radios licensed for SmartSDR v1, the SmartLink feature introduced in SmartSDR v2, along with the multiFlex, is not included in SmartSDR v4 Basic.

SmartSDR+ is an optional one-year new feature license.

When you purchase a SmartSDR+ feature license, you gain or retain access to all prior SmartSDR v2 and v3 major features, as well as all new SmartSDR v4 major features released during your one-year license period.

All new SmartSDR v4 features are only available immediately for SmartSDR+ Early Access feature license radios.

Radios that have a SmartSDR+ feature license will gain access to the new features approximately 30 days later with a follow-up SmartSDR v4 software release.

To get the new SmartSDR v4 features immediately, a SmartSDR+ Early Access license is required (see below).

When your one-year feature license expires, you retain all features received during that period—you never lose them.

To gain access to any new features introduced after your license period ends, simply renew your SmartSDR+ license for an additional year.

SmartSDR+ Early Access is an optional one-year SmartSDR+ feature license that provides all the benefits of SmartSDR+, with the added advantage of early access to new features approximately 30 days before they are available for standard SmartSDR+ feature license holders.

As part of the Early Access Program, participants are invited to share feedback with the software engineering and product management teams based on their experience with the preview software.

This collaboration helps shape and refine future SmartSDR releases.

Important Release Information Before upgrading, please read all sections marked as IMPORTANT for upgrade prerequisites and other important information.

Important Notice: Beginning with SmartSDR v4.0.1, the SmartSDR hardware license installed on your radio must be revalidated or updated after purchasing a SmartSDR+ Feature License by connecting to the SmartSDR License Server.

To complete this process, ensure that your radio is connected to a network with Internet access.

The radio will automatically download any new licenses when it is booted.

Once your SmartSDR license has been successfully validated, the radio will not need to reconnect to the License Server unless you purchase a new SmartSDR+ feature license.

Page 2 | Copyright 2025 FlexRadio, Inc. | SmartSDR v4.1.3 Release Notes | SmartSDR+ v4.1.3 New SmartSDR+ Early Access Features: There are no SmartSDR+ Early Access Features included in this software release.

New SmartSDR+ Features: Below are the SmartSDR+ Early Access 4.0.1 features now enabled for SmartSDR+ Feature License users.

Feature Description Supported Radio Models

SMART-11431

New DSP Noise Mitigation: We have updated and added a variety of new noise reduction/mitigation algorithms to the Aurora, FLEX-8000, and FLEX-8000 series radios.

The new noise mitigation features are designed to cater to different types of noises, environments, and setups.

Multiple Noise Mitigation functions can be used simultaneously.

Toggle the various noise mitigation functions on and off to taste.

NRF

1

• Spectral Subtraction Filtering Algorithm

NRS

1

• Spectral Subtraction with Voice Detection

RNN

1

• AI Noise Reduction

NRL

1,2

• NR algorithm using LMS (Least Mean Squares)

ANFL

1,2

• ANF algorithm using LMS

ANFT

1,2

• ANF algorithm using FFT (Fast Fourier Transform) 1 Aurora 1 FLEX-8000s 2 FLEX-6000s

SMART-3985

Digital Voice Keyer: Digital Voice Keyer (DVK) allows recording, playback, and transmission of up to 12 voice recordings stored on the radio. Aurora FLEX-8000s FLEX-6000s

SMART-10570

Enhanced Signal Clarity (ESC): ESC is a unique diversity reception feature that is only available on dual SCU radios.

Enhanced Signal Clarity (ESC) in diversity.

ESC combines signals from multiple antennas to optimize audio receive capabilities via beamforming/null forming.

Used to accentuate desired signals (constructive interference patterns) or to remove undesired signals (destructive interference patterns) to improve signal quality.

This does not affect the displayed panadapter or waterfall, but metering will be affected.

AU-520(M)

FLEX-8600(M)

FLEX-6700

FLEX-6600(M)

SMART-9958

Relative Noise Floor Scaling: This feature automatically adjusts the displayed noise floor to maintain a visually consistent reference level as you operate on different bands and antennas.

This feature makes it easier to compare signal strengths and visually interpret band conditions.

Aurora FLEX-8000s

SMART-11332

CW Auto Tune: Introducing CW Auto Tune.

CW Auto Tune automatically tunes the active slice receiver to CW signals within the passband, simplifying the process of locking onto CW transmissions.

There are two modes of operation: One-Shot or Intermittent Mode.  One Shot - Auto tunes once to the highest signal on the click of the AUTOTUNE button  Intermittent – Continuously auto-tunes to the highest signal every two seconds while the AUTOTUNE button remains enabled.

Aurora FLEX-8000s FLEX-6000s Page 3 | Copyright 2025 FlexRadio, Inc. | SmartSDR v4.1.3 Release Notes | New SmartSDR Basic Features and Bug Fixes: Below are the new minor feature enhancements and bug fixes available to all radios running SmartSDR Basic.

Please refer to the SmartSDR v4 Changelog for a complete listing of all SmartSDR v4 software and firmware changes.

Feature/Defect Description Software support of the Aurora radios AU-51​0(M) and AU-520(M)

SMART-12007

Improved database migration between updates. It is still required to factory reset your radio after a software downgrade

SMART-11578

Fixed NRL operational inconsistencies

SMART-11900

Fixed NR operational inconsistencies

SMART-11902

Fixed NR operation during transmit

SMART-12033

Fixed an issue where NR muted Slice B

SMART-11923

Fixed NR status message errors

SMART-11977

Fixed ANFT removing all audio when directly on top of an AM carrier

SMART-11986

Fixed ANFL not working on SSB

SMART-11987

Fixed NB for FLEX-6000 Series Radios

SMART-11744

Fixed an issue where DAX audio was briefly transmitted at the time of PTT

SMART-11799

Fixed a profile Import/Export bug

SMART-11995

Fixed the MIC and TX profile issue where not all settings were saved

SMART-11885

• Fixed issue affecting FLEX-6000 Series, where a snare drum-like noise would happen when turning
• NR off with NRL enabled
• SMART-11899 Moved the Maestro DVK menu up to just below Memory

SMART-11973

Fixed the Maestro DVK Menu needing to be scrolled to see the subscription notification

SMART-11974

Fixed Maestro DVK Menu displaying the keyboard, but not allowing edits

SMART-11998

• Fixed multiple F-key selections of DVK overriding each other
• SMART-11955 The Escape key now stops DVK playback in progress

SMART-12028

Improved error handling and reporting of DVK imports

SMART-12055

Improved DVK F-keys experience on Maestro

SMART-11910

• Fixed the brief display issue with blank panels when launching SmartSDR
• SMART-11914 Noise Mitigation options are now