Elecraft K3S
firmware v4.51
Elecraft · Released May 9, 2012 · First seen Sep 14, 2026
Source:
elecraft.com
v4.51 is not the latest firmware for the Elecraft K3S: the current version is v5.67 (January 22, 2019). Go to v5.67
In short — summary by updatemystuff.com
AGC improvements enable higher thresholds and clearer signal reception in pile-ups and noisy conditions.
- AGC threshold now adjustable to much higher values
- More monotonic AGC response curves for improved clarity
- Noise reduction and autoNotch work at all threshold settings
Written from Elecraft's release notes, which are printed in full below.
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What's in this update
MCU 4.51 / DSP 2.76
- AGC IMPROVEMENTS: AGC threshold (CONFIG: AGC THR) can now be set much higher, and the AGC has better (more monotonic) response curves. Greatly improves signal clarity in pile-ups and other high-noise or dense-signal situations, especially with threshold set to 12 or higher. NR and autoNotch can be used at all threshold settings.
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