I haven’t run a model on a hytower recently but helped one soul out of a
quandary with one a while back. Items that required attention:
1) Coax connection SO239 at base and its mounting device metal, etc, had to
be entirely replaced due to metallic corrosion.
2) Radials were awful. Needed serious work to get past the “terrible”
rating up to “really poor but that will have to do”. Property had fairly
severe irregular elevation and boundaries.
3) When 1), 2) dealt with, 160 SWR got worse because feed R wasn’t anywhere
near 50 any more.
4) Cheep skinny coax had to be replaced.
5) Owner's opinion, results clearly better but still not good. It still was
a short vertical *without* a full size, dense, uniform length and spacing
radial field.
I don’t recall the coil being an issue, other than the SWR bandwidth was
narrowing down with repairs/improvements.
He did try an L off the hytower top later which improved things a bit more.
But at root it was still a short 160 vertical over a necessarily poor
radial field.
For the umpity-umpth time, for 160, the two ton elephant in the room is the
counterpole to whatever will be the aerial radiator. We whack down a
DI-pole to a monopole which now needs a substitute pole for the missing
pole, a counterpole, usually referred to as radials or counterpoise. If
that counterpole is inferior, so will be your results.
First solve the radial/counterpoise elephant efficiently. Then do a tuning
something or other to handle the physical law that efficient shortened
antennas have reduced band width.
Someone posted about a vertical dipole. Absent discussion about size, cost,
difficulty of construction, support, feed method, survivability in weather,
yada, yada, it DOES solve the counterpole problem. At least for as long as
it stays up.
If all that was adequately solved by something durable off the shelf or
easily constructed, everyone would have a vertical dipole on 160. But we
all can count the number of 160 vertical dipoles around.
There ARE a few of those on the AM broadcast band. They are all
unbelievable MONSTER antennas that make your jaw drop if you ever get to
see one in person. They DO work very well. And they occupy monster acreage
for the guy lines, etc.
See k2av.com for one answer to a necessarily poor radial field.
73, Guy K2AV
On Sat, May 8, 2021 at 6:12 AM Rob Atkinson <ranchorobbo@gmail.com> wrote:
> No personal experience but I've heard repeatedly over the years that
> the inverted L kit works way better than the loading coil. This makes
> sense. I think the inverted L kit consists of a trap you hang off
> the top of the BX section. You probably supply the wire but on that
> I'm not sure. I don't know if this kit is still being made or not but
> you might be able to fabricate a trap yourself.
>
> Rob
> K5UJ
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