Elecraft K3S firmware v1.65

• TUNE POWER le​vel menu entry (TUN PWR). This determines the power level used when the TUNE switch is pressed. The default, "NOR", uses the power knob setting.

Alternatively, the value can be set to any power level from 0.1-120 W.

• REAL-TIME-CLOCK display now keeps accurate time. The RTC IC itself was running accurately, but the VFO B time display was running about 9% slow.
• MODE SWITCH now only cycles thorugh one sideband (LSB or USB) on each band -- not both. Saves time when switching modes, especially useful in contest situations.

Use the ALT switch (hold the left end of MODE) to switch between LSB and USB (per-band). NOTE: As a result of this change, you may need to re-select the desired sideband on some bands. You'll only have to do this once.

• S-METER ACCURACY Improved. Suggest using SMTR SC=14 and SMTR OF=24 (these are the normal defaults).
• EXTERNAL CW TIMING IMPROVED: Corrected rise/fall time assymmetry. Internal and external keyers should now be closely matched in weighting.

NOTE: You may need to reduce the weight of external keying, if you had increased it to compensate.

• AMTOR RX/TX turnaround times improved. To do this, we'​ve created a variation of SSB and DATA modes called SYNC DATA. It should only be used with modes like AMTOR that require the fastest possible turnaround time. To turn on SYNC DATA, first locate the SYNC DT menu entry (SYNC DATA), and assign it to any programmable function switch (PF1, PF2, M1 tap or hold, M2 tap or hold, etc.). Then use this programmable switch to enable SYNC DATA. The -S mode icon appears. This setup can be enabled separately for SSB or DATA modes. (The actual turnaround times will vary with crystal filter selection. Further improvements may be possible and are being explored.)