It is my experience that buried radial length is not terribly important so
they would semi-work with a phased array. Elevated radials should be
resonate so if you cut them short you would require loading coils in each
(short) radial, which would restrict the bandwidth of the array. To make
them resonant just install two radial as if they were a dipole, measure the
resonant frequency (an MFJ-259 works great for this) and trim, or adjust the
loading coil.
de Paul, W8AEF
----- Original Message -----
From: "Gammmatec" <gamma.tec@t-online.de>
To: <towertalk@contesting.com>
Sent: Tuesday, March 04, 2003 12:27 PM
Subject: [TowerTalk] 80m vertical array questions
> Hello everybody,
>
> Beginning of spring starts thinking of antenna improvement for 80m.
> I?m living in the flat north of DL and my backyard is an empty grasfield,
around 40m x 40m or 130ft x 130ft, so very good for a radial system.
> No problem to set up a lambda/4 vertical for 80m with the ultimate numbers
of radials (Only a question of time for the km or miles of laying
wires...).
> But, is it possible to put an array on it ?
> I mean, the backyard is not large enough for the needed radial-lengths for
an array.
> Will I get the extra performance from that array with limited radials,
compared to one vertical with nearly perfect radial-system ?
> Next question, which array (2, 3 or 4) and which distances between the
elements could work on that limited backyard ?
> Btw., the property is larger, but blocked with my house. It?s possible to
lay down some extra, longer radials in direction W and SW.
> Has anybody tried another form of a 4-array, a kind of "Mercedes"-star,
one vertical in the middle and 3 others around, separated 120 degrees and
spaced lambda/8 from the center ?
> I found nothing everywhere about this constellation.
> Yes, the ON4UN-handbook is on my side, of course...
>
>
> Many thanks for answers and 73 de Andr? DF9OX
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