In the ideal case of course you have just receiver noise as your
background noise level. So you adjust your sound card input to give you
the magic 0dB on that. During the night the static crash level will
rise and push the S-meter to s9 at times. Every 15 minutes G4JNT will
do its one minute of transmission on 503.7 at various power levels and
push the little thing in the box well into the red. So one has to ask
oneself what exactly the dB figures in reports really mean. The
adjustment to 0dB will differ widely between different stations
depending on what the noise level was at the time they adjusted it. And
as pointed out, 0dB in WSPR with an SSB bandwidth (but only looking at
200Hz of it) usually implies a signal way over s9 in anybody's terms.
End result, pay no attention to the figure other than a relative
measure of any individual stations reception, or to monitor QSB. It
certainly doesn't mean that a -30dB report is 30dB below audible
copy...
Anyway, I have now given up on WSPR for the moment. Any chance of
another Wolf transmission before I disconnect the antenna?
73 Dave G3YMC
On 24 Sep 2009 at 9:18, Dave Pick wrote:
> opt-tee-mumish? These technical terms always confuse me....
>
> ;-) Dave
>
>
> 2009/9/24 Laurence BY3A-KL1X China <[email protected]>
>
> > Red box means its either too low (or recommended level) or too high -
> > if
> > the box goes White its in the ballpark but Im told 0dB is
> > opt-tee-mumish
> >
> > --
> G3YXM IO92BK Birmingham UK
>
http://www.davesergeant.com
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