[Elecraft] K3 and preamp

[Per-Tore Aasestrand]

Have a look here:

http://en.m.wikipedia.org/wiki/Stochastic_resonance

P-T
LA7NO


On 10 September 2014 01:24, Chuck Smallhouse <w7cs at theriver.com> wrote:

> Dave, N7AIG,
>
> Please define "stochastic resonance",  a new term for me, which may
> apparently aid in weak signal detection.
>
> When I was very active on 2M CW EME, in order to better detect very weak
> signals below the noise, I played all kinds of adjustment games with the CW
> BW, tone and IF shaping of my TS-930S.  For my needs (type of noise) it had
> by far the best NB that I've ever used.  In addition, I also used an Autek
> QF-1 external audio filtering system, centered at about 400 Hz and an
> estimated 25 Hz audio BW.  It did not ring when adjusted properly.  By dumb
> luck and extensive experimenting, I discovered that the least expensive
> (cheapest) headphones that Radio  Shack sold, had a strong mechanical
> (audio peak ?) resonance, also at 400 Hz.
>
> My hearing (unadmitted at the time) had also like Fred's, had been exposed
> to many, many very, very loud noises, during one of my careers, and
> suffered greatly from Tinitus and overall hearing impairment.  It happened
> that my preferred or best CW weak signal copying frequency, was 400 Hz.
>
> Anyway when the searched for very weak signal ( sometimes > -10 dB below
> the noise) lined up with all the adjusted BWs, it just seemed to "pop" out
> of noise and become detectable.
>
> So Dave, is this at all related to, or similar to  " stochastic
> resonance"  ?
>
> Chuck,  W7CS
>
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