"Dave Richardson" wrote in message ...
Hi thanks for reading.
I'm trying to maximise the DX capabilities of my new HF2V/160S on top band.
Butternut recommend top loading wires, mainly for increasing the bandwidth
but some say this reduces the effective height, leading to detrimental
effects as a DX antenna?

Effective height? I don't see where they get that at...The height of
the vertical radiator is still the same. Top loading by wires is very
effective. It's much less lossy that inductive loading, and you will
need fewer coil turns to tune than without the top loading wires. But
there is another advantage. The current distribution is improved, and
will be much more constant along the vertical section, than without
the top loading.

Also, mine sways around like a whip in the wind so I'd imagine the loading
wires would have to be very slack?

I'd use them as extra guy wires, and tighten them up a bit to cut the
swaying.

I dont particularly need extra bandwidth so am unsure whether to go to the
bother?

The improved current distribution alone is worth it on 160m.

Do you have any experience of top loading this or similar LF antennas?

I run one here. It's actually my 80m turnstile and 40 dipole fed with
a single coax feedline. On 160m, I short the coax together at the
shack, and feed as a top loaded vertical. Mine is appx 42 ft tall, and
uses four 60 ft loading wires, along with the two 32 ft wires. I've
modeled it, and the current distribution along the vertical section is
nearly constant, and it has an overhead null and pattern much the same
as a monopole. How does it work? I have a 1/4 wave inverted L about 45
ft up a tree. Only very early in the evening when the skip is straight
up and back down is it ever better than the top load antenna. "due to
the horizontal componant of the inv L" Most all other times, the top
load vertical is better. Usually by about 5-10 db on the average
radio's meter. I'm fairly sure the increase in performance is due to
the improved current distribution. Both antennas are the same appx
height. This also reduces ground losses a bit since the current level
near the ground is lower.
MK