[Elecraft] P3 artifacts

[Hank P]

Couple questions:

1.Can some Guru tell me where the little spikes at +/-  300 and 600 cycles 
from the CW  carrier  (down about 40 dB) are when looking at a -73 dBm  from 
a  XG1 or XG2 ?

2. I am curious what you typically see for the delta in dB  between the 
average baseline say at 10 msec averaging and the peak line on the P3 with 
no antenna on the K3.

73 Hank K7HP

K 3.7 / P 3.1 /KAT500/KPA500