DSP terminology question

[n8ewy]

Can anyone explain terminology associated with the DSP unit.  It's difficult
to know which way to begin adjusting individual areas of the DSP without
understanding.  At least for me.  I realize I could fiddle with them and
listen for change, but I'm not comfortable with that without a little
knowledge going in.

 

Terms such as:

 

1. soft filtering and standard filtering
2. Adjusting the "Beta (aggressiveness)" in the Denoiser
3. Adjusting the "hold/decay"  time of the filter in Denoiser
4. The same in the autonotch
5. I guess I'm unclear what effect the autonotch is having on the
signal in SSB.  It is difficult to detect any difference with it on or off.
6. "Denoiser Gain" sttings and there effect.
7. "Filter gain" and balancing the audio gain.

 

I guess I need an expert in all things DSP.  I just want to understand them
better before tinkering with them.

 

Thanks in advance if there is info available from anyone.

 

Dohn  N8EWY

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[KK7P]

> Can anyone explain terminology associated with the DSP unit...
> 1. soft filtering and standard filtering

Standard has steeper skirt selectivity.

> 2. Adjusting the "Beta (aggressiveness)" in the Denoiser
> 3. Adjusting the "hold/decay"  time of the filter in Denoiser
> 4. The same in the autonotch

See the KDSP2 Manual Glossary pages 45 and 46 for a definition of these
terms.

The easiest way to translate these definitions into understanding is to
listen to some signals and change the parameter from 99 to 00 and back
(just one tap does it).  You'll then get a good idea what each parameter
does.

> 5. I guess I'm unclear what effect the autonotch is having on the
> signal in SSB.  It is difficult to detect any difference with it on or off.

If there is no carrier to notch, then it will do very little.  Tune in
the 4 MHz birdie on the K2 in SSB mode.  Then turn the autonotch on and
off and you'll hear what it is doing.  The, with it turned on, vary a
parameter between 00 and 99 and then tune the radio 100 Hz or so and
listen to how it cancels the tone.  After you tune with all four
combinations 00/99, 99/99, 99/00 and 00/00) you should have a pretty
good idea what these parameters do.

In general, I leave autonotch on to eliminate annoying carriers while I
tune around in SSB mode.

> 6. "Denoiser Gain" sttings and there effect.

Leave CW set a 0.0 dB.

Goto SSB and tune in a voice signal.  Turn the denoiser on and then
adjust the SSB denoiser gain so the voice audio is about the same when
you turn the denoiser on and off.  7.0 dB is reasonably close for more
normal settings of the Denoiser parameters.

> 7. "Filter gain" and balancing the audio gain.

These are present for audio balancing purposes and normally will just be
left at 0.0 dB.

DO NOT USE THE FILTER GAIN MENUS TO INCREASE THE OVERALL GAIN OF THE K2!
  If you do, you may have too much gain with strong signals, especially
if the AGC is turned off.

> I guess I need an expert in all things DSP.  I just want to understand them
> better before tinkering with them.

73,

Lyle KK7P

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