Elecraft K3S firmware v1.75

MCU 1.75 / DSP 1.57

• SSB TRANSMIT Improvements:

This is the first phase of our effort to make SSB transmit setup and use more consistent with operator expectaions. Changes so far include:

• Higher signal-to-noise radio at both mic jacks, as well as LINE IN
• Livelier and easier to use transmit-mode metering (CMP, ALC, SWR, POWER)
• Better optimized TX EQ menu function
• More effective compression (CMP)
• Greatly reduced distortion with CMP set to 0 (for audi​o data modes, high-fidelity speech, and two-tone testing with an external audio generator) (Planned for next release: Improved low-frequency response and adjustable TX passband.) Note on MIC gain setup: To properly adjust MIC gain, first set CMP to 0, then adjust MIC gain for about 5 bars on the ALC meter (it should not hit 6 bars during normal speech).

Then set CMP for the desired compression amount.

• 2 USER-DEFINED "NORM" filter setups for each mode:

Now, in addition to the K3's "NORM" values, you can save two of your own often-used filter setups in each mode, and recall them using the NORM function.

The new NORM values are named ALT1 and ALT2.

To save a filter setup, hold NORM until you see "<- SAV ->" (3 seconds), then rotate the knob left or right to save it as ALT1 or ALT2. (The arrows to the left and right of "SAV" are a reminder that you can rotate the knob left or right go get to the "ALTernate" filter memories.) To recall, hold NORM until you see "<- NOR ->" (about 1/2 second), then rotate the knob left or right to recall ALT1 or ALT2.

Note: Wh​enever you normalize the filter passband via NORM, ALT1, or ALT2, two "wings" appear on the DSP filter passband graphic.

Moving any DSP control makes the wings disappear, as a reminder that the passband is no longer normlized.

• DUAL PASSBAND Bandwidth Restore: On exit from DUAL PB, the previous CW bandwidth is restored.