Try to get them as far apart as you can. 10 to 12 feet is the minimum. My
attempt at a W2PV 12 meter antenna wiped out 10 and 15 on the KT34XA and the
W2PV. I found less interaction with my 12 meter X beam. Does not affect 12
but I do have some interaction on 15. The KT34XA is weakest on 15 of the
three bands. I don't detect any change in SWR but the patern is skewed and
the front to back is not all it should be. The X beam shows a 1.9 to 1 SWR
on 21.4. They are only 6.5 feet apart.
The 40 meter beam interacts with both 15 and 17 (as it works well on 17 and
can be made to work on 15). If I could find a big beam that works as well
as the KT34XA on 20 and 10 plus the WARC bands and 15 I would switch.
Having just two beams up on the tower (I can get them 14 feet apart) would
make a simplier arrangement. Two locals (one has moved) have the Sommer
beams and they seem to work well the draw back is they are HEAVY!. One
local has the TH-11 and as with the TH6 and 7 its best on 15 but takes a
back seat to the KT34XA on 10 and especially 20.
73 Dave K4JRB
>
> I have been reading the various messages about 40m beams and 10-15-20
tribanders
> with interest, but I've got one question. Are there any noticeable
interaction
> problems between a tribander and the various small 12 & 17 meter WARC band
> beams?
>
> I've got a Mosley Classic 33 WARC which just has a rotatable dipole on the
WARC
> bands, but one of the small 3-element WARC beams, usually 10 ft or less
boom
> length, would seem to offer enhanced performance over the dipole, 0 db
gain for
> the dipole, vs 6-9 db claimed gain for the small WARC beams made by
various
> manufacturers. Currently I use a 15 ft. .125 inch wall steel mast with
the
> Mosley about six inches above the thrust bearing on a TriEx WT51 50 foot
crankup
> and a Cushcraft AR270 2m/440 vertical on top of the mast to access the
local DX
> packet cluster.
>
> I'm sure the best thing to do might be to just scrap the Mosley and get a
5 band
> beam of some type that had multiple WARC band elements?
>
>
> Tom, WW5L
>
>
>
>
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