Topbanders,
Over the past two years or so I have been using all manner of 'aerial'
supports for Top Band aerials. Some have prompted, as Tom W8JI commented,
"UFO reports in the neighbourhood", others have tested the patience of those
same neighbours when an unexpected wind change drifts them into TV antennas,
but all in all it is the best way to get some wire up into sky without a lot
of steel and planning permission hassles.
The best four ways, in order of success and ease of deployment, are:
1. The Light Weight Helikite, made here in the UK by Allsopp Helikites.
Earlier reports on this reflector said it won't support an antenna. Wrong,
it will. You have to carefully consider what it was deigned to do and how
to use it to the best advantage. Originally designed to scare birds off of
farm fields, it is a combination of kite and helium balloon. It has a
design spec of 60 grams of lift in no wind, 180 grams in a wind (up to 25
miles per hour). Rarely is there 'no wind' so about 100 grams is the
average I have used as my rule of thumb. It comes in an envelope with the
kite, five silver Mylar balloons, a fibreglass spar, and the kite line.
Very small and I used it in Israel a few times as 4X/G4VGO. Helium
canisters about the size of a very small fire extinguisher are available
here in the UK from Midget Widget and they travel well also.
I use CAT 5 cable, stripped of the insulation on the bundle with one
conductor pulled out, and that is taped to the kite line (very light,
supplied by Allsopp and rated at mult-hundreds of pounds of breaking strain)
with about a metre left dangling down to keep high voltage away from the
kite line. This is the top 20 or 30 metres. This is attached to the top of
my telescoping pump up mast (a NATO surplus SCAM12) with a 5 metre
fibreglass extension on top. The ground system of my conventional vertical
is used in this configuration. The Helikite locks up at a 45 to 50 degree
angle of flight and you have a very good, very high inverted "L" antenna
that is good for contesting and great for both Europe and DX.
The Light Weight Helikite will not fly in rain, so that is a low to medium
winds, fair weather combination.
2. The Sky Hook Helikite, also from Allsopp, significantly larger, rated at
400 grams in no winds, 1.5 kg in a wind up to 30 mph, and it will fly in the
rain. I use heavier wire, more of it, and it goes up to about 60 metres
(the max legal height in the UK and most other places) and it will lock off
at a higher angle of flight, stay up in a stronger wind, and rain doesn't
make it come down in the middle of the night. A killer support, and not as
large as a pure balloon so the gas cost is still very small. It lives on
the top of the mast like its little brother and with 200 watts I get regular
reports of the loudest signal out of the UK.
3. Weather balloon (about 7 feet, from Fair and other sources). Very
helium hungry, and really only good for light winds. I use number 14
flexiweave wire, it goes up to the 60 metre legal max, and is more of a pure
vertical. Rain and snow won't bring it down but wind over about force 2
will make it a menace as it will start to go horizontal. At night I use
three LED's with two AA cells on the balloon neck to keep track of it and in
case a 747 hits it at 200 feet it was 'beaconed'.
4. Kites, French Signal and composite triangle box/delta types, good for
really strong winds, angle of flight is nearly vertical, and because they
are rip-stop nylon they shed rain and snow. I have had them stay up in 50
mph winds with a 200 foot vertical taped to the line with a bungee cord at
the top to take the strain off of the antenna wire. Again a killer vertical
on Top Band. The LED beacon is also used to see it at night.
The country total has now hit 210 from a VERY SMALL back yard. High power,
400 watts here in the UK, is rarely used, the FT1000D barefoot into the SGC
antenna tuner is all I usually use.
One thing that never fails, gales force winds are scheduled for contest
weekends here in England and probably will be for the next millennium, so I
always have the 10 metre fibreglass pole ready to put on top of the mast as
a last resort.
If anyone needs photos, good/bad advice, or help with aerial aerials, just
email me direct.
Hope this helps.
Bob G4VGO
rmread@attglobal.net
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