At 03:12 PM 1/10/02 -0000, Sain'T Tom wrote:
>
> I once used 2 of the same 3 element 15 meter yagis simultaneously from
>my old QTH in South Carolina. One was at 70 feet on the tower top and was
>rotatable. The other was fixed on Europe at 40 feet. Both had electrically
>equivalent (same electrical length) feed lines of RG213.
>
> Reports from Europe generally, but not always, gave the stack a slightly
>stronger signal report. The lower sometimes would be reported just as
>strong as the upper, but NEVER was it reported that the lower was stronger.
I think band and sunspot cycle phase have a lot to do with this.
Certainly, as N4KG says, if you can have multiple antennas there are lots
of reasons to do so, including but not limited to stacking. But if you can
only have one, and particularly if it is a tribander, somewhere between 75
and 100 feet is very nice indeed, but I'm not sure it makes a lot of
difference which end of that range you're at.
My 2-high stack of C-3Es is at 97 and 69 feet, and I have only heard
signals louder on the lower antenna than the upper one, on any band, on one
or two occasions. My hunch is that if I had a third antenna at 32-33 feet,
there's a greater chance that I'd notice differences between single
antennas, but most of the time, the whole stack together would still be
best.
73, Pete N4ZR
The revised World Contest
Station Database
is online at www.pvrc.org
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