The Hustler 5BTV vertical is a good option for hams on a small lot. To get
full performance out of it, you need to do some work. There is a ground
screen under this vertical. I used up two quarter mile rolls of electric
fence wire. The ones in the direction of Europe and North Africa and the
Middle East are up to 700 ft long. There is a CURRENT balun 1:1 for a choke
on the feedline. NEVER use voltage baluns.
One item you may be interested in: the 75 Meter modification employing a
standard 40 Meter trap such as that used in the Alpha Delta or Unadilla
multiband dipoles. These are rated full legal limit. They are low loss. The
stock 5BTV 80 Meter top loading coil is nearly identical to their mobile
antenna top loading antenna. The stock one is very narrow band due to its
reduced size. I propped up the 4BTV section of the Hustler vertical on my
porch and built a bracket to hold the new trap. I then added two sections
of wire for a capacitance hat shown in the photos. I used red wire so it
would appear in the picture well. The approximate wire length is about 20
to 25 feet for resonance on 3790. You will have to adjust the lengths to
tune to your section of the band. You can use one wire for an inverted L,
but it will be significantly longer; in that case, you will not get a
symmetrical vertical pattern, but will get some high angle radiation in the
direction opposite from the single wire. Some people use four wires; in
that case, the length of the wires are shorter than the two wire top hat.
The two wire top hat does not increase the foot print of the 5BTV vertical
beyond reasonable space in a city lot. Four wire top hats are smaller.
An MFJ259 is real handy for the adjustment.
Be aware that changing from the small stock Hustler 80 meter coil to this
configuration boosts performance more than 6 dB with a good ground,
according to QST discussions in the September 2014 issue. It also handles
full legal limit. Further, it delivers more band width.
It does require retuning of the 40 meter length. 40 meter bandwidth and
tuning is only slightly affected. You may have to cut a few inches off the
bottom of that section. That is also true if you install the 30 meter trap.
The 30 meter trap will be added later.
I hope to put this to use this winter with the new ALS-1300 amplifier.
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