The 80 Meter Butternut HF2V Vertical
Dawn Christmas Day 2005 at GM7NVA. The 32' Butternut
HF2V 80m vertical mounted 25 feet above ground. Total around
57'. The antenna was relocated in late 2004 from a ground location
(note the 40 meter Butternut site elsewhere on this site) to explore
the use of elevated 1/4 wave radials. This aerial has 4 elevated
radials (not visible here - low visual impact) at 20 feet and
the far ends are at 5-10 feet over ground.
If there is one thing that can be said about this antenna
it is this: here in Scotland we are prone to gusty winds. This
antenna stood up to two weeks of constant battering by 70mph +
winds and during a storm over the 24 hours of January 7-8th 2005,
it was tested by 90mph gusts while 20 feet up and in the clear.
Obviously the antenna is guyed. The great thing here is that the
guy line is lightweight. The Butternut is a very light antenna.
My guy line is only #6 stranded orange sea-fishing hand-line.
It is so light even the top section can be loosely guyed. More
than 50 feet away from the installation the guys are all but invisible
(See picture above). This makes the vertical a very low impact
installation. (OK, it's a 32 foot vertical but, it's amazing how
much you forget it is there). I have now tied the guys to the
house rainwater pipe wall-fixings. So overall the antenna footprint
is very small.
The 80 / 40 meter coils just above the feed point.
The 40 is not in use.
Matching and loading coils with the radial feed point
at 20' above ground. With only 4 elevated radials installed this
antenna was compared to a nearby full sized (65') quarter wave
vertical (gm0vhr) ground mounted with 60 radials,laid on the ground.
Both stations were running 350 watts. The rigs were FT1000MPs
with Heil headsets and the amps Heatherlite Explorers. Both rigs
were set up the same with the processors on. On an 80 meter test
running across some 3 months in late 2004 to east cost USA between
11pm - 4am UTC, in poor to average conditions, the full sized
vertical was on average, around 1 S-point stronger on just about
every antenna type you could imagine. However, a lot of the time
both systems were reported as equal and on a few occasios the
elevated ground plane was marginally stronger.
Taking into account the fact that this is only a 3-4,000
mile path with a probable average radiation angle of 10-15 degrees
and that the Butternut is a short antenna, not a quarter wave
antenna, then it has performed very efficiently and therefore
the case for using 4-8 elevated radials at 20-25 feet rather than
60-120 ground radials becomes a very attractive proposition. Especially
in locations of limited space and where low environmental impact
is required. Just for the record, a long haul contact to 7J4AAL
on his sunrise into our darkness, in poor conditions, received
a 5x5 and in the morning about sunrise (8am) from Scotland a 5x7
was achieved with another JA station. VK is usually 5x6 - 5x9
in good conditions using 350 - 400w. The signal to Europe almost
always peaks around 5x9+ . The antenna has worked all but 4 (2,7,19
and 31) of the world zones during 2004 near the bottom of the
sun spot cycle on 80meters.
The only drawback that we noted during the test was
this: vertical antennas are prone to picking up general noise.
Colin, GM0VHR was using Beverage receiving antennas and I was
not. He was able to both hear and therefore work stations that
I could not. So, although you may be putting out a respectable
signal, you may not be hearing the stations that are hearing or
calling you! At this point we can recommend that if you have the
space: BULD BEVERAGES! It's like you had been deaf all of your
life and suddenly you can hear AND you can hear without all that
static crashing in your ears to boot! If you do not have space
for the ultimate rx antenna go for the K9AY
loop system. One last thing... always always use good quality
headphones. (Heil 'Proset
Plus' are recommended). Even this can make the difference.
Recommended suppliers of specialist receiving antennas
AYtechnologies /
Array Solutions
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