Elecraft KX3 firmware v1.10

MCU 1.10 / DSP 0.94

• AUTO-NOTCH (AN) ADDED: Auto-notch can be used to automatically reject interfering constant carriers in SSB and AM modes. (In all other modes, manual notch is available.) To turn auto-notch on/off, hold the NT​CH switch. Note: Auto-notch is not available when AGC is turned off.
• NOISE REDUCTION (NR) ADDED: Receive noise reduction reduces the amplitude of random noise while preserving desired signals. (RX NR is different from the VFO NR menu setting, which can be used to reduce VFO tuning noise on the higher bands.) NR works in CW, SSB, and AM modes. NR has a characteristic “hollow” sound. To turn NR on/off, hold the NR switch. Also see RX NR x menu entry, below. Note: NR is not available when AGC is turned off.
• RX NR x MENU ENTRY ADDED: Allows the user to customize receive noise reduction (NR). The letter appearing at x in the menu entry name shows which parameter is being adjusted: B (beta; tap 1), D (decay; tap 2), or M (wet/dry mix; tap 3). The defaults are recommended, and this menu entry is locked to prevent accidental changes. The NR settings for CW are separate from those for voice modes.

Using the RX NR menu entry: Unlock the parameter by holding KHZ for about 3 seconds; the VFO A loc​k icon will disappear.

Then tap 1, 2, or 3 to select a parameter to change.

You can turn NR on/off while in the menu to test its effectiveness.

The default beta is 5 for CW and 10 for voice modes.

A lower beta will further reduce noise, but may attenuate weak signals.

The default decay is 240.

A much lower decay value will allow NR to track fading signals better, at the expense of somewhat worse noise rejection.

The mix value determines how much of the signal is “dry” (unprocessed) vs. “wet” (processed).

The default is 220 in CW mode and 250 in voice modesessentially “all wet”.

You might want to use a lower mix number to reduce the “hollow” sound or to minimize the effect of NR on weak signals.

• KXBC3 BATTERY CHARGER/RTC SUPPORT (BAT CHG MENU ENTRY): To use this menu entry, you must have a KXBC3 module and a set of internal batteries installed. ONLY NiMH BATTERIES CAN BE CHARGED. Other battery types can be installed to use the real-time clock and power the radio, but attempting to charge them could damage your KX3, cause a fire or acid leak, or other hazard. This will also void your warranty. Refer to the KXBC3 instruction manual for further details.