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R400a Firmware Revision History


This model is not capable of firmware updates in the field so no files are available for download. Contact Lectrosonics if you need a firmware update.


R400a v1.7 - 14 October 2022

  • Fix bug causing frequencies chosen with Smart Tune to be "forgotten" after cycling power (not stored to non-volatile memory).

R400a v1.6 - 01 November 2018

  • Add "Nu Hybrid" compatibility mode for use with newer digital hybrid transmitters.

R400a v1.5 - 03 July 2013

  • Enhanced squelch system to be immune to high intensity supersonic content in the audio.
  • Improved dynamic tracking accuracy in compatibility mode 6.

R400a v1.4 - 16 May 2012

  • Applied sonic refinements to mode 3. Improved response to sharp acoustic transients.
  • TX battery status now more accurate for lithium batteries.

R400a v1.3 - 21 February 2008

Added block 944. Will be a separate build, labeled r400a_900mhz.hex.

R400a v1.2 - 21 February 2008

Added low blocks 470, 19, and 20.

R400a v1.1 - 15 August 2005

  • Added compatibility mode 6.
  • Dynamic noise reduction (DNR) now driven by supersonic noise, not RSSI level.
  • Out of range window detector voltage no longer forces the receiver to squelch once a signal has been acquired. However, it remains true that an in-range window detector voltage is required for a squelched receiver to *unsquelch* when a carrier is present.
  • SmartTune function now disabled when controls are locked.

R400a v1.0 - 11 April 2005

First production release.