Elecraft K3S
firmware v1.70
Elecraft · Released Feb 20, 2008 · First seen Sep 14, 2026
Source:
elecraft.com
v1.70 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
Improved ATU matching for high-Q loads, added RIT/XIT offset display, and blocked transmit 7.5-9 MHz.
- ATU matching uses more extensive search on second tap within 5 seconds
- RIT/XIT offset display added before voltage readout
- Transmit blocked from 7.5-9 MHz to prevent equipment damage
Written from Elecraft's release notes, which are printed in full below.
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What's in this update
- [#94] ATU MATCHING IMPROVED: If operator taps ATU TUNE a second time on the same band/antenna within 5 seconds, a more extensive search is used. Dramatically improved performance in tests with some high-Q (narrow-band) loads. Original (fast) algorithm is unchanged.
- [#243] RIT/XIT OFFSET DISPLAY MODE ADDED (right after date, before voltage). This is especially useful with CW-to-PSK31, where the operator may be quite conscious of the required RIT offset, or for those using RIT during contesting.
- [#322] RTTY CWT INDICATOR UNSTUCK (was getting stuck when PITCH was accessed).
- [#275] Tapping XMIT during CW message playback both stops the message *and* exits transmit mode.
- [#199] SSB filter BW steps now 100 Hz up to 3 kHz, then 200 Hz.
- [#292] NON-VOX CW no longer has any delay after transmit termination (i.e., release of PTT or exit from XMIT).
- [#236] Switching of antennas during tune is not allowed (this was fixed some time ago).
- [#285] Tapping transmit-related multifunction encoders briefly displays the present parameter value (SPEED/MIC/CMP/PWR). Double-tap to display the existing parameter (since this switches first to the alternate, then back).
- [#305] Tapping filter-related multifunction function encoders briefly displays the present parameter value (SHIFT/LOCUT/HICUT/WIDTH). Double-tap to display the existing parameter.
- TRANSMIT BLOCKED from 7.500 to 8.999 MHz (to prevent possible damage to the KAT3/KANT3 traps). This range is blocked even if the customer has unblocked transmit using our software "MARS enable" utility. It is only usable in milliwatt-power mode (KXV3).
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