Building a vertical dipole configuration with the Buddipole Deluxe Kit
Mark J Culross KD5RXT (updated June 6th, 2010)
I have previously posted a couple of messages on the Buddipole Yahoo! Group regarding my use
of the Buddipole Deluxe Kit & the different configurations that I have experimented with (the
traditional horizontal dipole, the VersaTee vertical w/ counterpoise wire, & most recently the
vertical dipole).
The CBP has been referred to as “the tinker toys of ham radio” in the sense that, when it comes
to assembling different antenna configurations with the Buddipole, “if you can imagine it, you
can certainly build it”. Among the features that the Buddipole is famous for, its versatility is
second only to its quality, portability & applicability!!
Here is my description of how I specifically assemble & configure the vertical dipole
configuration of the Buddipole:
Standard pieces & parts:
1 x tripod & 8-foot mast
1 x VersaTee
2 x 22” arms
1 x red coil
1 x black coil
2 x collapsible whips (black or stainless, long preferred, but short will certainly work)
Added pieces & parts:
1 x TRSB
1 x BNC to VersaTee adapter cable (comes with the TRSB)
1 x 50’ RG-58 coax w/ male BNC connectors at each end
1 x Rotating Arm Kit (part of the Deluxe Kit, consisting of 2 pieces referred to as RAKs & 2
soft-knobs for attaching them to the other parts in the system)
Other pieces & parts:
3 x 1-gallon plastic jugs filled with water
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Building a vertical dipole configuration with the Buddipole Deluxe Kit
Mark J Culross KD5RXT (updated June 6th, 2010)
Building the vertical dipole configuration:
1.
start out setting up the vertical dipole (a slightly modified version of the traditional
horizontal dipole) as follows (see photo #1 below)
2.
the "up” leg consists of (starting from the VersaTee & building out) 22” arm, RAK (w/
soft-knob), red coil, long collapsible whip pointing vertically up
3.
the "down” leg consists of (starting from the VersaTee & building out) 22" arm, RAK (w/
soft-knob), black coil, long collapsible whip pointing vertically down
4.
looking from above (or below), the antenna extends straight out 22" parallel to the
VersaTee to the left & right, then makes a right-angle turn on each leg, where the “up”
leg continues perpendicular to the VersaTee, but pointing upward, and the “down” leg
continues perpendicular to the VersaTee, but pointing downward
5.
I prefer to extend the whip on the “up” leg to its full length & adjust tuning by tweaking
the length of the whip on the "down" leg as much as possible (because of its ease of
accessibility) . . . occasionally, you might need to lower the antenna & tweak either the
whip or the coil on the "up" leg, but this has to be done by observing the resonant
frequency when the antenna is fully extended vertically (frequency is too high or too low
. . . again, I use the MFJ-269 antenna analyzer to make this step easier) & making the
adjustments accordingly while the antenna is lowered & then returning the antenna to its
fully extended vertical deployment to do a final check and/or to operate. See table #1
below for the settings that have worked for me (as always, use these as a guide and/or
starting point & adjust from there for your particular operating conditions).
Table #1 – Vertical Dipole settings (for KD5RXT)
Band
Center Red Black
SWR
Freq Coil Coil
Rs
Xs
Low Freq High Freq
Whips
(SWR=2:1) (SWR=2:1)
40M
7.250
28
22
1.1:1
50
6
7.160
7.390
Long
20M
14.250
6
9
1.0:1
51
4
13.614
14.730
Long
17M
18.200
1/3
4 2/3
1.0:1
50
1
17.250
19.280
Long
40M
7.250
37
N/C
1.4:1
63
6
7.237
7.263
Short
20M
14.250
11
12
1.1:1
51
8
14.168
14.329
Short
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Red
Black
TRSB
Whip
Whip
all
all
1:1
sections sections
all
all
sections
1:1
sections
– 12”
all
all
1:1
sections sections
all
all
sections sections
4:1
– 2”
– 3”
all
all
sections sections
4:1
– 1”
– 2”
Building a vertical dipole configuration with the Buddipole Deluxe Kit
Mark J Culross KD5RXT (updated June 6th, 2010)
To the left of the VersaTee in photo #1 below, you can clearly see the 22” arm screwed directly
into the VersaTee & extending to the left, with the RAK connected to it using the soft-knob,
which forms the base for the “up” leg of the vertical dipole. You can also clearly see the 22”
arm screwed directly into the VersaTee & extending to the right, with the RAK connected to it
using the soft-knob, which forms the base for the “down” leg of the vertical dipole. Connected
to each RAK, you can see the bottom of the long whips forming the remainder of each leg.
Photo #1 – vertical dipole (looking up slightly from below) showing the components
extending out from the VersaTee
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Building a vertical dipole configuration with the Buddipole Deluxe Kit
Mark J Culross KD5RXT (updated June 6th, 2010)
Here’s a close-up view (see photo #2 below) of the VersaTee & TRSB. Note that I have a
permanent coil balun comprised of 13-turns of coax, approximately 9” in diameter, held in place
using cable ties (wound using approximately 30’ of coax…nothing particularly magical about
that size & length…that’s the piece of coax that I had laying around !!) & connected to the 50’ of
coax & located at the antenna. I don’t know if it’s absolutely necessary, but this is one of those
“no-cost insurance” fixes for a common RF problem & I take much comfort in the fact that I
have NEVER had any “RF on the coax shield” problems that others have reported !!
Photo #2 – close-up view of the VersaTee & TRSB & coil balun
Page 4 of 9
Building a vertical dipole configuration with the Buddipole Deluxe Kit
Mark J Culross KD5RXT (updated June 6th, 2010)
Photo #3 below shows the close-up detail of the two RAKs & coils attached to the end of the 22”
arms. The antenna is assembled this way in particular to keep the “down” leg of the vertical
dipole from being interfered with by the tripod. This was something that bothered me in my
early attempts at assembling the vertical dipole configuration. By using the 22” arms as this
document describes (horizontally), it works around this annoying physical interference problem
nicely.
Photo #3 – close-up view of the two coils & RAKs
See photo #4 below for a view of the fully deployed Buddipole vertical dipole.
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Building a vertical dipole configuration with the Buddipole Deluxe Kit
Mark J Culross KD5RXT (updated June 6th, 2010)
Photo #4 – the fully deployed vertical dipole configuration
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Building a vertical dipole configuration with the Buddipole Deluxe Kit
Mark J Culross KD5RXT (updated June 6th, 2010)
Now, if you’ve read this far, you’re probably still wondering what the 3 x 1-gallon plastic jugs
are for (although photo #4 gives it away). As I have mentioned in some of my other Buddipole
Yahoo! Group postings, when I purchased the CBP Deluxe Kit at Hamcom in Texas, as a
hamfest special bonus, Budd & Chris gave me a choice of either the guy-kit or the counterpoise
wire. At that time, I chose the guy-wire kit (thinking that I'd mostly be operating the horizontal
dipole configuration, not the VersaTee vertical configuration, so I did not necessarily need the
wire). As it turns out, I have actually never used the guy kit since I got it (and it really is such a
nice guy kit) !!
Instead, I prefer to just suspend 3 x 1-gallon plastic jugs full of water to weight down the bottom
of the mast (with 3 individual strings that each go around one leg of the tripod, specifically
making one loop where the support member connects to each leg of the tripod & this leaves the
three jugs suspended just above but not touching the ground). In this way, the 3 x 1-gallon
plastic jugs of water act as a sufficient counter-balance to the weight of the upper dipole
assembly (see photo #5 below).
This particular configuration has allowed my CBP, setup in all different configurations, most
notably the vertical dipole configuration, to survive some surprise Texas thunderstorms with
high winds at Boy Scout Summer Camp where I didn't have the chance to get the CBP down
before the storm blew through (too busy getting the radio, etc. under cover) & this also works
especially well in making the whole assembly very steady.
Page 7 of 9
Building a vertical dipole configuration with the Buddipole Deluxe Kit
Mark J Culross KD5RXT (updated June 6th, 2010)
Photo #5 – view of the tripod with the three 1-gallon plastic water jugs as ballast
Page 8 of 9
Building a vertical dipole configuration with the Buddipole Deluxe Kit
Mark J Culross KD5RXT (updated June 6th, 2010)
I hope that the description here of my approach for building the vertical dipole configuration
using the infinitely versatile Buddipole antenna system is sufficient to allow others to repeat
what I have done. I also hope that you get as much satisfaction in doing so as I certainly have
been fortunate enough to experience.
If you have any questions, please feel free to contact me via e-mail. And finally, as I always say,
good luck & most of all, have fun!!
Mark J Culross, KD5RXT
[email protected]
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