[Elecraft] Audio artifacts in DATA A mode with KX3

[Nicklas Johnson]

Jörg in the Elecraft KX3 group on Facebook had an interesting observation:
with WJST's waterfall, if the "flatten" mode is on, it produces some
unusual artifacts in the presence of sharp spectrum drop-offs, and indeed
if I turn off the "flatten" feature and manually set the zero point for the
waterfall, the artifacts go away.

It's still an open question as to why the data-a mode has a steep drop-off
at 400Hz when the PBT settings on the rig would seem to indicate otherwise,
and the same drop-off isn't there in USB mode.

I see searching on "400 Hz" that GM4JJJ had the same question here on the
last back in July 2015, but never really got an answer.  I basically have
the same question as this one:
https://www.mail-archive.com/elecraft@mailman.qth.net/msg183837.html

   Nick


On 2 January 2017 at 12:06, Nicklas Johnson <nick at n6ol.us> wrote:

> I'm seeing some unexpected audio artifacts when using DATA A mode with the
> latest production firmware on my KX3, on all bands.  This is something I
> observe when the PBT BW is set all the way wide (4KHz) and FC is centered.
>
> In DATA mode, there's an audio drop-off between 200 and 325 Hz, with an
> almost completely dead audio "hole" between 250 and 300 Hz.  Then there's
> some additional noise between 350 and 500 Hz.
>
> If I switch to USB mode (with no EQ or audio effects applied, naturally),
> all of these artifacts go away, and it's perfectly smooth across the
> spectrum.  No drop-off, no noise.
>
> Pictures of the waterfalls for comparison here: http://imgur.com/a/AjHu4
>
> Am I doing something wrong, or is there something I should check?  I've
> taken the usual steps, but it's plausible I've missed something.
>
> ​   Nick​
>
> --
> *N6OL*
> Saying something doesn't make it true.  Belief in something doesn't make
> it real. And if you have to lie to support a position, that position is not
> worth supporting.
>



-- 
*N6OL*
Saying something doesn't make it true.  Belief in something doesn't make it
real. And if you have to lie to support a position, that position is not
worth supporting.