Elecraft K3S
firmware v5.57
Elecraft · Released Feb 16, 2017 · First seen Sep 14, 2026
Source:
elecraft.com
v5.57 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
Faster response to high reflected power, automatically reducing drive and restoring power when antenna match improves.
- Faster drive reduction when reflected power spikes
- Automatic power restoration when antenna impedance improves
Written from Elecraft's release notes, which are printed in full below.
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What's in this update
MCU 5.57 / DSP 2.88 / FPF 1.26
- FASTER RESPONSE TO HIGH REFLECTED POWER: The transceiver will now reduce drive more quickly when transient conditions cause excessive reflected power. This roll-back response does not change the set power level (PWR knob); instead, it reduces the drive to get below the reflected power limit. This means that once a better match is restored (such as when using an antenna tuner), the set power level will automatically be restored.
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