[Elecraft] [K3] Noise Reduction Recording

[Tom Hammond]

Hi David:

I hear NO NOISE (at all) on any of your recordings!

Well... what 'noise' I do hear is (to me anyway) 'band noise'... atmospheric
noise and not electro-mechanical noises such as would normally be classified
as 'line noise' or man-made. This actually a pretty good demonstration is a
nice, CLEAR 75-meter band... I certainly wish I had MY 80/75 m band noise to
be THAT low level all of the time.

The BACKGROUND (band noise) which you hear on this band is NORMAL and should
not be considered to be unusual. And there is NO noise blanker of which I am
aware that will remove what you recorded. However, enabling the [NR], Noise
Reduction feature of the K3 will help to significantly REDUCE the level of
the background noise, albeit lending a slightly 'watery' sound to the real
received signal... we seldom get something for nothing these days.

73,

Tom Hammond   N0SS

At 02:47 02/25/2008, David Ferrington, M0XDF wrote:
>I'm still having trouble determining if what I hear is noise that NB should
>get rid of. This is because I'm a relatively new Ham without the experience
>to know what I'm hearing.
>
>So I have made a recording on the noise and it is available from
><http://homepage.mac.com/davidferrington/FileSharing2.html>
>
>I have recorded 3.740MHz in 5 second tracks with a tone between each change
>of NR setting, viz:
>     5 seconds of no NR, 200mS tone @ 700Hz
>     5 seconds of NR F1-1, 100mS tone at 1400Hz
>     5 seconds of NR F1-2, 100mS tone at 1400Hz
>     5 seconds of NR F1-3, 100mS tone at 1400Hz
>     5 seconds of NR F1-4, 200mS tone at 700Hz
>     5 seconds of NR F2-1, 100mS tone at 1400Hz
>     etc.
>
>I have found no NB setting that affects this, I can possibly hear a very
>slight change, but it does not cancel the noise.
>I can do the same for the NB settings if people wish.
>
>I would appreciate some feedback on this please, is this just broadband hash
>in my urban neighbourhood from er, broadband and wall warts etc?
>
>Mail me off list if you'd like me to mail you a copy of the file direct.
>
>73 de M0XDF / K3 #174
>
>--
>Why should I fear death? If I am, death is not. If death is, I am not. Why
>should I fear that which cannot exist when I do?
>-Epicurus, philosopher (c. 341-270 BCE)
>
>
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