Here are some question for anyone with more tech skills than me;
My compromise vertical at 8Q7BM is made of thin wire attached to a DX-Wire 15
meter glass fibre pole. The vertical wire goes all the way up, but as the
pole’s top sections are very thin/weak the three top loading spokes (each 12
meter long) are attached at about 13 meter. The antenna has a 1/4 elevate
radial towards the water at 2-3 meter height. The whole structure is within 1/4
wave of the water line.
The antenna is self resonant at 2.2 MHz and I use a coil wound on a water
bottle to bring it down to 1.8. The coil appears to be about 8-10 uH according
to online calculators.
My questions are;
How much I can improve by moving the coil up. What improvement should I expect
if center loading at about 7 meter? How about moving the coil all the way up to
the top loading spokes? Is it worth the effort? (the pole won’t support much up
there).
My top loading spokes are sloping more than the recommended angle. According to
the ON4UN Low Band book I got the impression that the difference should be
minimal when close to salt water. I have tried to slope them less, but easily
get in trouble with the weak pole in the wind. And there are pats to the beach
every where so options are few.
Which one of the two above actions would be the most beneficial? Move the
loading coil higher up or rearrange the top loading spokes for a better angle?
73 de Björn,
SM0MDG
8Q7BM
SE0X
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