Elecraft K3S
firmware v4.36
Elecraft · Released Apr 20, 2011 · First seen Sep 14, 2026
Source:
elecraft.com
v4.36 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
KPA500 amplifier integration adds band switching, fault status display, and separate per-band power control.
- KPA500 band switches can change K3 band when connected via ACC cable
- Per-band power control with separate settings for amplifier use versus barefoot, marked with asterisk
- UP & DN remote commands now update P3
Written from Elecraft's release notes, which are printed in full below.
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What's in this update
MCU 4.36 / DSP 2.73
- KPA500-TO-K3 BAND CHANGE, FAULT/STATUS, and POWER CONTROL: If the KPA500 is connected to the K3 via the ACC cable (including auxBus and band data lines), the following new features will be available:
(1) the amps band switches can change the K3s band (2) amp faults and operate/standby changes will be reported on the K3 display (3) if CONFIG: PWR SET = PER-BAND, the K3 will provide two separate sets of per-band power levels: one for use with the KPA500, one for barefoot use (amp in standby).
If the amp power levels are in effect, an asterisk is added to the K3s power control display (e.g.
Ò30 W*Ó).
This should eliminate the need to adjust the K3s power control when changing bands or switching the amp between operate and standby.
- REF*CAL ASTERISK BLINKS DURING K3EXREF DATA RECEIPT.
- UP & DN REMOTE COMMANDS NOW UPDATE P3.
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