[Elecraft] K3 new V3.25 NR not so good for CW week signal

[Brett Howard]

You can pull this off by looking at the filter setup in the K3Config
utility or you can find it in the menu of the K3.

~Brett (KC7OTG)

On Sun, 2009-08-16 at 02:12 +0000, dave.wilburn at verizon.net wrote:
> What is the best way of determining the gain setting?  Seem to recall an app for this. 
> 
> David Wilburn
> NM4M 
> Sent from my Verizon Wireless BlackBerry
> 
> -----Original Message-----
> From: Brett Howard <brett at livecomputers.com>
> 
> Date: Sat, 15 Aug 2009 15:51:46 
> To: Merv Schweigert<k9fd at flex.com>
> Cc: <Elecraft at mailman.qth.net>
> Subject: Re: [Elecraft] K3 new V3.25 NR not so good for CW week signal
> 
> 
> Not saying I'd do it.  (and I'm not with the 8 filters I have in my
> radio) but one can if thats what they wish to do.
> 
> ~Brett
> 
> On Sat, 2009-08-15 at 12:42 -1000, Merv Schweigert wrote:
> > Not really,  if you read the recommendations for the filters you will
> > notice 
> > that caution is warranted for setting the gain higher than
> > recommended, 
> > for IMD prevention if I remember correct.   Kind of like the Inrad
> > roofing
> > filters,  in some cases the gain is set to high and causes more IMD
> > than
> > without the filter. 
> > Some Inrad roofers for the FT-1000D had too much gain and the radio
> > was worse with them installed than without.  W8JI had some
> > measurements
> > on those issues.  
> > Merv KH7C
> > > This is sorta already there if you have multiple roofing filters.  You
> > > can define the gain that is added when each filter kicks in.
> > > 
> > > 
> > > On Sat, 2009-08-15 at 13:50 -0600, William Carver wrote:
> > >   
> > > > I've noticed in homebrew receivers as the bandwidth narrowed, shedding
> > > > noise and QRM I preferred the gain to go up, increaseing the in-passband
> > > > signal amplitude. I always attributed it to formative years with a
> > > > Heathkit Q multiplier. It may be an effect similar to AGC with
> > > > adjustable flatness (May 1996 analog circuit, in DSP of K3). I found I
> > > > preferred to have strong signals sound louder rather than perfectly
> > > > flat. Prolly a psycho-acoustic explanation (or maybe just get my head
> > > > examined?).
> > > > 
> > > > In firmware one could increase the audio gain by an adjustable amount as
> > > > the IF bandwidth was decreased, with an operator-settable scaling
> > > > number. Say 0 = gain independent of bandwidth, to 100 = gain multiplied
> > > > by K * (2800/DSP bandwidth). Very similar to the AGC rise scaling. That
> > > > sounds good to me.
> > > > 
> > > > 
> > > > 
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