It's also very important to add the ideal current
distribution in unidirectional arrays is NOT when power
distribution is equal. As a matter of fact, optimum
distribution in an array like this is NEVER when power is
equal, and it is NEVER when element impedances are equal.
73, Tom W8JI
----- Original Message -----
From: <k1ttt@arrl.net>
To: "Al Williams" <alwilliams@olywa.net>
Cc: "towertalk" <towertalk@contesting.com>
Sent: Wednesday, November 17, 2004 11:38 AM
Subject: Re: [TowerTalk] dump power?
> in a typical hybrid network used for dividing power and
creating phase
> shifts in a 4-square vertical array or many other types of
arrays there is
> a point in the circuit where any imbalance between the
loads has to 'go
> somewhere'... to prevent this imbalance in loads from
badly affecting the
> pattern the power at this point is 'dumped' to a dummy
load. if the array
> is perfectly designed and matches the design impedances
all around the
> 'dump power' is zero. this is rarely the case as when you
change
> frequency away from the design center the impedances will
change and more
> power gets 'dumped'. it can also be caused by other
objects in the
> vicinity that unbalance the array, or from changes in the
ground plane
> under vertical arrays, etc. so one measure of how good
your 4-square is
> performing is to measure the 'dump power'.
>
> > I did a google search on "dump power" and got 149 hits
including two of
> > Tom's towertalk posting.
> > Other hits ranged from John Deere's tractors to garbage
dumps but at
> > least two others indicated that it is a common term used
in power lines
> > and also integrated circuit power line layout.
> >
> > I suspect that some other Towertalkians are like me and
it is an
> > unfamiliar term. We will appreciate an explanation?
> >
> > k7puc
> >
> > _______________________________________________
> >
> > See: http://www.mscomputer.com for "Self Supporting
Towers", "Wireless
> > Weather Stations", and lot's more. Call Toll Free,
1-800-333-9041 with
> > any questions and ask for Sherman, W2FLA.
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
> >
>
>
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting
Towers", "Wireless Weather Stations", and lot's more. Call
Toll Free, 1-800-333-9041 with any questions and ask for
Sherman, W2FLA.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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