In the late
1980's I was absorbed by the work of K1FO in his pursuit of a VHF and
UHF antenna with a great pattern and gain and of course read every work
I could get from the then famous HAM RADIO magazine. I chose
to start building 8 of his then experimental 32 element yagis for 432
MHz in the hope I could get going on 432 EME. To build these I traveled
to Perth on a holiday to visit Robert VK6KRC and invaded his "toy shop"
to use his jigs and tools while he was at work, many thanks Bob.
Now 20 year later I have finally completed one of the yagis
and have it at the very top of my tower. While his design (K1FO)
focused on using the Delron button insulators and clips, in my
ignorance I just used what ever correction factors I could lay my hands
on to change it to 1/4" elements and no insulators and then in the
ultimate insult through a folded dipole at it (original design was for
a T match).
I am sure it is no where near where it should be in freq or gain but it
seems to work for me, so maybe I was just lucky or the design is very
forgiving in my blunders. I hope to have an alternative design going
soom (YU7EF) so maybe then I can compare how bad or good it turned out
:-)
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| mounting the free side of the folded dipole. The white nylon is from a cutting board and is NOT fairing well in the UV. |
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Side view of my folded dipole, with a mix of K1FO style 4:1 BALUN made from UT141 hardline and a clasic folded dipole
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| End view before putting on the boom end cap or weather proofing. |
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| top view of the feed, the BALUN provides some of the mechanical stability for the folded dipole. |
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| Looking at this now I realise the GAP
between the dipole is way too wide, maybe thats why the best I could
achive was 1.7:1 who knows |
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| okay, no
prizes for noticing I have feft the lift rope tied onto the boom
(left). Yes there were some words spoken to myself.. grumble
grumble |