[Skimmertalk] CW frequencies for 6m?

[Björn Ekelund]

Thanks Bob and Wes,

Very interesting. I'm currently in SM0 but I will check how things look
with my RP when back in SM7 this weekend.
I seriously doubt one RP differs from another, so I will probably see the
same.
With 96kHz sub band width, there is plenty of wiggle room for fitting a
70kHz CW segment into the bandwidth.

73,

Björn



Den tors 6 dec. 2018 kl 18:23 skrev Bob Wilson, N6TV <n6tv at arrl.net>:

> On Thu, Dec 6, 2018 at 6:40 AM Björn Ekelund <bjorn at ekelund.nu> wrote:
>
> > I did know that sensitivity rolls off close to the edges of the sampled
> > subband, but I thought this catered for by
> > the difference between the 182kHz "bandwidth" (twice the center offset)
> and
> > 192kHz "sample width".
> > Or have I got this wrong?
> >
>
> With those default settings on a Red Pitaya, using CWSL_Extio and HDSDR, I
> could still see reduced sensitivity (roll-off) *above* the band edge, so I
> shifted all the center frequencies down by another 6 kHz (for 192 kHz
> spans), and by 3 kHz (for 96 kHz spans,) and by 1.5 kHz (for 48 kHz spans).
>
> More details and links to a screen shot here:
>
> https://groups.io/g/RBN-OPS/message/1793
>
> However, if the noise floor doesn't seem to roll off at all above the band
> edges with your Red Pitaya, then there's no need to make any changes.  It
> all depends on what you're seeing with HDSDR and your RP.
>
> 73,
> Bob, N6TV
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