[Elecraft] [KX3] Can someone help explain this - AM/LSB/CW Freq

[Gary Hawkins]

I was playing around with an RigExperts AA-54 antenna analyzer today 
using it as a signal source for the KX3.  I fed the AA-54 into a Alex 
Loop inside the house and had the KX3 connected to my mini-G5RV 
outside.  I set the AA-54 to do continuous spot measurements at approx 
14.082MHz.  In this mode the AA-54 excites briefly approx once per 
second at the chosen frequency.

Using HDSDR connected to the I/Q output of the KX3 via computer in CW 
mode I observed a pulsing signal peak at 14,081,530Hz.  In LSB mode I 
observe the signal peak 14,082,127Hz.  In AM mode I observe the pulsing 
peak on HDSDR at 14,071,114Hz.  I get the difference between the first 
two measurements (600Hz side-tone), I don't understand the results for 
AM display.

Now if I tune the KX3 manually and listen for the signal I get the 
following, LSB strong S9 1KHz pulsing tone at approx 14,082,600, CW 
strong pulsing tone S9 zero-beating tone at 14,082,108 and finally AM 
weak peak (S2) pulse at approx.14,081,800Hz.  These measurements make 
more sense but don't explain what I'm seeing using HDSDR monitoring AM 
obtained from KX3 I/Q.

Any thoughts on what I'm seeing, particularly regarding AM?

73's Gary K6YOA