[Elecraft] KX3 PBT on SSB

[Mike WA8BXN]

Hi Dana, 
 
As I understand it, the IQ output from the KX3 is before the "roofing filter
 and DSP. Thus any bandwidth settings you have on the KX3 should not have
any effect on the IQ output. You did not mention what particular program you
are using on your computer. If you are exchanging data between the KX3 and
that program, I would suggest you disconnect the cable that allows that and
see what happens. It could be that the issue lies in the program and not the
KX3. 
 
73 - Mike WA8BXN 
 
 
 
 
 
-------Original Message------- 
 
From: Dana Browne AD5VC 
Date: 3/4/2013 10:46:52 PM 
To: Elecraft Mailing List 
Subject: [Elecraft] KX3 PBT on SSB 
 
I have been using my KX3 with digital software and seem to have some odd
behavior using the PBT. I have it set to do upper cutoff/lower cutoff on USB
or LSB and am watching the received display on the waterfall. As expected,
the upper cutoff in the noise follows the cutoff displayed on the screen, up
to a point. 
 
However, if I lower the cutoff below 2.35 kHz, there is an additional dead
zone (no noise on the display) from 1.4 kHz to 1.6 kHz. The same thing
happens on LSU at 2.45 kHz. This appears no matter what band I am on, so I
assume it is something in the DSP software. 
 
No such dead zone appears if I raise the lower cutoff. 
 
 
I am using MCU 1.36 and DSP 1.05. 
 
Has anyone else observed this? 
Dana Browne 
AD5VC