One comment on 432 MHz LFAs: I have built two of the 18 el LFAs. I had some
problems initially getting them to match correctly. My elements are insulated
in Stauff clamps above a square aluminum boom. Eventually I figured out that
the boom correction I was using (taken from a well-known website) was
incorrect. Once I corrected that the antenna SWR curve matched the model very
closely and it seems to work great.
Tor N4OGW
On Thursday, August 21, 2025 at 12:57:16 PM CDT, David R Buckwalter via
VHFcontesting <vhfcontesting@contesting.com> wrote:
Several years ago I discovered LFAs and went on an antenna building binge.
I built 4 each LFAs for the 144, 222 & 432 bands. 222 and 144 were the
easiest to get going with a decent match & SWR. Last year I modified the
222MHz 12 element LFAs into dual polarization. They work ok and having
switchable polarization has helped with some EME contacts, but I am just not
satisfied with the overall performance. The 432 LFAs were real challenge,
and I just struggled until I had something that worked. I was not impressed
with the performance at all and last fall I replaced them with 4 newly built
21 element K1FOs (Hpol only) and it made the world of difference, both
terrestrial and EME. I am amazed how many new stations I have worked on
70cm, both off the moon and terrestrial, and I get great signal reports most
of the time. This is what I remembered from the K1FOs I had built and used
in the 1980s & 90s. The 144 LFAs on the other hand seem to perform quite
well and I have had little concern with them, other than they are not big
enough! But what antennas really are big enough? They are H-Pol only and
I use them for both terrestrial and EME and am currently 8 states from
completing 2m WAS.
Today I started the process of building 4 new 5wl K1FOs for the 222 band.
I have struggled mentally with deciding if I should build them dual
polarization or H-Pol only. I have 36 states confirmed on the 222 band.
Of the remaining states needed, 8 or possibly 9 will have to be worked off
the moon. The remaining can be worked via meteor scatter. Even though
dual polarization has proven an advantage for EME, I have decided the new
K1FOs will be H-Pol only. Did I make the right decision?
Dave - K3SK
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