[Elecraft] K3 and Preamp

[Don Wilhelm]

Bud,

I think a lot has to do with the 'material between the ears'.  Some have 
developed the ability to hear signals that to my ears are buried in the 
noise.  Those chasing Low Band DX are examples of folks with that 
ability.  Some report using a wide bandwidth while others report good 
results with a narrow bandwidth.  I believe it all depends on the "brain 
training".  The human brain can provide a wonderful filter if you know 
what to pay attention to (and ignore things that can distract).  Some 
have it while others do not.  It may be something that can be learned, 
but I have not accomplished that feat.

73,
Don W3FPR

On 9/6/2014 5:28 PM, W2RU - Bud Hippisley wrote:
> On Sep 6, 2014, at 2:34 17PM, Dauer, Edward <edauer at law.du.edu> wrote:
>
>> I received a couple of off-list comments that might be of interest to
>> those who are following this thread.  One was that narrowing the BW also
>> improves the S/N.
> Maybe.  Maybe not.  Or, maybe up to a point.
>
> I believe that whether one observes monotonic improvement in ability to decipher the intelligence carried in a very weak signal as one reduces receiver BW will be a function of _how_ the BW is narrowed in the various electronic circuits and/or digital algorithms, as well as a function of our own individual hearing characteristics.
>
> Perhaps I am not on the main part of the normalcy distribution curve (my close friends will assure me I’m _not_!) but I know for a fact that many, many times I have been best able to pull intelligible information out of a very weak CW signal on the low bands by using a receiver BW somewhat _wider_ than that provided by my narrowest filtering options.  I have used primarily Kenwoods and (more recently) the K3 for most of my serious low-band DXing efforts, but I can’t tell you if this effect is more or less apparent in one model vs. any other.
>
> I am also a strong believer in what I have been told is “stochastic resonance” as an aid to hearing and copying the intelligence carried in weak signals.   I have found repeatedly, for instance, that I am more apt to hear certain “unusual” vehicle sounds from the engine compartment or underbody when I have the car radio playing music within a certain range of amplitudes.   Of course, that might also depend on my choice of music genre … :-)
>
>