Elecraft K3S
firmware v2.03
Elecraft · Released Jun 9, 2008 · First seen Sep 14, 2026
Source:
elecraft.com
v2.03 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
Band change, power reading, and mode commands improved; EXT ALC adjusted.
- PC band change command now saves mode settings to preserve per-mode bandwidth
- PC power reading command corrected for external amplifier status
- EXT ALC voltages adjusted; mode command fixed for 6m and data modes
Written from Elecraft's release notes, which are printed in full below.
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What's in this update
MCU 2.03 / DSP 1.78
Misc:
- EXT ALC voltages adjusted to match resistors called out in EXT ALC mod document.
PC Control Command Changes (for application software developers):
- "PC" (PWR READ) IN K22 MODE now supplies correct value for QRO (KPA3) on/off.
- ÒFA/FBÓ BAND CHANGE now saves mode for old band before switching to new band.
This prevents problems with per-mode bandwidth, etc., following band changes.
- ÒMDÓ COMMAND FIXED: On 6 m, CW norm/reverse were being reported backwards.
On all bands, DATA A and PSK-D were reversed for both get and set (AFSK A and FSK-D were correct).
NOTES: When an ÒMDÓ command is used to switch between data normal and reverse, it applies to both DATA A and PSK-D (if either of these was in effect), or AFSK A and FSK-D (if either of these was in effect).
To get/set data modes, use ÒSWH43;Ó to emulate pressing the DATA MD switch, then ÒDBÓ to retrieve the data mode text string from VFO B, and ÒUPB;Ó / ÒDNB;Ó to change the mode.
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