This bounced when I tried to send it directly to Peter.
--------- Begin forwarded message ----------
From: N4KG
To: Peter_Chadwick@mitel.com
Subject: Re: [AMPS] ssb power
To: <amps@contesting.com>
Date: Fri, 24 Jul 1998 05:50:57 -0600
Message-ID: <19980724.072314.9910.7.N4KG@juno.com>
On Thu, 23 Jul 1998 15:13:11 +0100 Peter Chadwick
<Peter_Chadwick@mitel.com> writes:
>
>I need convincing that 2dB makes an enormous difference.Even in the
>case of
>the early opening - late closing situation, remember that 2dB is
>barely
>noticeable aurally. I think many other factors, such as (and not
>limited to)
>speech quality or keying fist, tone, tiredness of operator, QRM/N
>level (and
>type), comfort of headphones and chair, external distractions, etc
>have more
>effect on the whole. Note that I'm talking HF, not moonbounce/VHF
>where the
>noise is pseudo white Gaussian (unless there's somebody about with 1KW
>from
>a pair of 4CX250Bs - that's a different set of bets). It will also be
>statistical: there will be occasions where 1.8dB makes a difference,
>ones
>where it doesn't. As far as S meters are concerned, S stands for
>suspicion.
>Although most are supposedly 6dB/S point, it's very approximate.
>
>73
>
>Peter G3RZP
Hello Peter,
A LARGE pileup on a single frequency sounds like white noise,
so basically you have the same detection problem as picking a
weak signal out of the background noise. In this case, your noise
level just rose to a much higher level!
I have heard contest tapes from PJ9 where nothing was heard but
a "hissing" noise, with an occassional voice riding above the din,
all by itself. People familiar with detection theory tell me only a few
dB is needed to rise above such a noise.
Please pass the "juice"!
de Tom N4KG
--------- End forwarded message ----------
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