Elecraft K3S firmware v4.42

MCU 4.42 / DSP 2.73

• 2-METER FREQUENCY LOCKING TO REF CAL & EXT. REF​:

The K144XV RFLK option locks the K3's 2-meter module to the rig's master reference.

Previously, users of this option had to enter offsets in the CONFIG: XVn OFS menu entry based on how far off the master reference was from 49380.000 kHz.

These offsets can now be calculated automatically based on the REF CAL menu entry.

If a K3EXREF module is also installed, then REF CAL itself is automatically calibrated based on an external 10-MHz reference (see K3EXREF on 2 m, below).

To enable this, locate XVn OFS in the menu, then tap 0 until you see ÒREFLOCKÓ.

This lets the K3 firmware know that the RFLK module is installed. (If the RFLK option is not installed, then the K144XVs oscillators are not locked to the K3s master reference.

The offsets should then be set according to the label on the transverter module.) To see the automatically calculated offset value in the XVn OFS menu entry, the K3 should be switched to the 2-meter band.

Otherwise, the K144XV offset parameter may be initially displayed as "-0.00".

K3EXREF on 2 m: If a K3EXREF module is installed, REF CAL itself will be automatically calibrated based on an external 10-MHz reference.

In this case, selecting ÒREFLOCKÓ for XVn OFS will allow the K144XV frequency to track this external reference. 2-meter frequency accuracy will be about a factor of around two worse than on HF, due to the higher frequency of the 2-meter local oscillators.

• K3EXREF REF CAL VALUE SAVE: In REF CAL, tapping '1' will now save the K3EXREF-deri​ved reference value as the manually entered value. This is useful in the event that the K3 is ever disconnected from the 10-MHz reference, as it will revert to the manually entered value. Note: To use this feature, a K3EXREF module must be installed, a 10-MHz external reference connected, and an asterisk (*) be present in the menu entry name (ÒREF*CALÓ).

You can then tap '1' to save the value.