[TowerTalk] perspective

[Brian Alsop]

Tom,

It depends on how you define proof.  Our past discussions indicate that
you want some kind of rigid scientific proof.  Nice if it could be had. 
Unfortunately we can't get mother nature to keep the propogation
constant over seconds, let alone over the duration of a rigerous test.

I think the best "theoretical argument" was given by N6BT(?) in QST.
It went like this.  If it takes a certain power to make a given path and
you only have half that level, you won't make it.  If you increase 3db
you will--ignoring the abilities of the hardware or operator to copy
signals beneath the noise.  The moonbounce guys used this accounting
method all the time to judge their chance of success.  

Given that things are not constant, the conclusions have to be couched
in statistical terms.  Does one increase his probability of making it
(or making more contacts --perhaps on a dead band or when backscatter is
the only prop mode) when 1 or 2 db is added to the overall system
output?  I think one could say with certainty that it does.  We don't
know whether that increase is 0.001%, 1% or 50%. It also not mean that
if one sits there for hours (prop changes) and keeps trying that one
won't make the path.   

The contester who is serious is trying to stack the odds in his favor. 
If 1 or 2 db will more than likely produce a few contacts or multipliers
more, he will probably go for it.  Many contests are decided by a few
contacts.  For what it is worth, August QST shows W4MR and K3KO with a
score of 101,634 points in the last 160M contest.  The number of QSO's
and multipliers were identical. (It is just a friendly cross town
rivalry). I can't say that 1 or 2 db would absolutely have helped either
one of us.  It MIGHT have resulted in another multiplier or QSO which
would have broken the tie.  

73 de Brian/K3KO 
Tom Rauch wrote:
> 
> > Contrary to the common perception, the reason for using monobanders is NOT
> > higher gain. Much more important aspect of monobanders are.
> >
> > Higher reliability due to simpler construction, less electrical joints to
> > fail and much lower wind drag.
> >
> > They don't detune as badly with ice or snow loads.
> >
> > Easier to design.
> >
> > The few extra db's are certainly a bonus, but reliability is the big
> > attraction for me.
> 
> I've been racking my brain trying to think of a way to test the theory
> that a few dB of signal makes a big difference in a contest, but I
> can't think of a way to prove or disprove it.
> 
> Can anyone?
> 
> 73, Tom W8JI
> w8ji@contesting.com
> 
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