|BUTTERNUT (Bencher); HF2V vertical Antenna. 33 ft vertical
--small city lot style -- "the building stage"
I bought a Butternut HF2V 80 and 40 meter vertical antenna. I'm the kind of ham that is not fond of wire antennas on my city lot. I dont have room
for many wires and the neighbours have enough of an eyesore to look at with my TV tower and small yagi antennas.
You can see the original HF2V in the laneway. Note: the guy wire collar. The previous owner used guy wires. I don't want guy wires or ropes
either. I want self supporting structures. My city lot is about 60 ft by 120 ft. Not enough room for large antennas and there are enough wires
courtesy our friendly neighbourhood utility company.
This antenna needed some TLC. I cleaned up the oxides and joint compounds. The joint compound was even used on the fiberglass insulators
which caused conductive streaks and a general mess. I actually completely replaced the old solid fiberglass rod insulators with some fiberglass
spreader arms I had around from a quad that I never put up.
The antenna has been in use for almost 2 years now and is my workhorse antenna. I use it on 80 and 40 mainly but I can clip on a base loading
coil of about 65 microhenry and it will load up fine on 160. I often do this to participate in a few 160 meter contests every once and awhile!
With the 160 coil in place, I cannot use the antenna on 80 or 40. I haven't got a radio for 30 meters yet. I want to use it on 30 as well. Bencher
(used to be Butternut) is the manufacturer and they do make add on kits for the HF2V to add on different bands.
To tell you the truth, I might just add a 1/4 wave sloper off the tower and forget about trying the HF2V for 30. THIS ARTICLE will cover all aspects
of the modification to the original HF2V and will show the swr curves that it currently exhibits in March 2011. I use an LDG automatic tuner in the
shack to tune this antenna and it works very well. RG8 coax is run to the antenna underground in a piece of irrigation tubing to protect the coax.
You can see pictures of the coax and the radials if you click on the link to the RADIALS and Ground system. The link is on this page.
Close up of the insulator separating the two coils. Note the black substance running from the joints. This is conductive grease streaks.
Made for a bad insulator. I decided to replace the insulator entirely with one I made myself out of a commercial quad spreader piece.
Where the insulators meet metal..I see no need for conductive grease. I might see some need for a substance to prevent the insulators
and the metal tubing from bonding together and making it almost impossible to take the assembly apart. I will be reading up on what to do
in this case.
The two coils and the doorknob capacitor assembly.
This assembly is about 3 ft or so up the antenna. tHAT IS WITH A CONVENTIONAL
OUT OF THE BOX HF2V..I made some changes as noted just below:
It does allow for easy ground level adjustments.
Top loading is more efficient. Some verticals are about 33 ft high with a large
inductance top loading coil at or near the top. MFJ makes an antenna like this. I
think the Cushcraft 8040 is also top loaded.
Above is the original vertical. It is not quite
stretched out its full length of 32 ft. This is before I
decided to do the modifications.
Some of the sections of aluminum are nested
together...which I did to transport the antenna
A guy ring is visible. I decided to go with heavier
aluminum tubing (which I bought) and a support
arm brace at about the 6 ft level. My vertical is
fairly stable in most wind situations and needs no
This is the base matching coil. The so-239 coax cable connects at
the base of this coil. The coil is optimized for 80 and 40 meters.
I may add 160 meters to my vertical system and I may have to read
up on how to build a coil which will work on 160, 80 and 40 with
reasonable comprimise results.
I measured this coil as 3 microhenry.
I will be replacing this coil with a base loading coil with taps at
3, and 6 and 1.5 uh. for specific matching for 80, 160 and 40 meters
6 uh might work for 160 and 80.
At the top of the vertical I will be adding a bolt at the end so that I
can try bolting on a top hat AND/OR ADDING A HUSTLER COIL to
bring the antenna to resonate on 160.
When there is a 160 meter contest or special event or something..I
want to be able to fold over the antenna and screw on a resonator
to allow reasonably efficient 160 meter operation.
I will be publishing the pictures as I move along with this project.
NOTE: for those interested in building antennas ..a company in the USA (MAX GAIN SYSTEMS) sells fiberglass rod in various diameters.
Another company that sells vertical antenna parts is DX Communications (also in USA).
With my large junk box I did not have to order any parts from them. I had some quad spreaders left over from a LIGHTNING BOLT quad that I
never did put up (YET). I sacrificed one of the spreader arms and made up a custom insulator for the 2 coils. This insulator is hollow
fiberglass but is reinforced with a
There is a YAHOO Group specifically dedicated to Butternut Verticals.
EI7BA has a good site with info on the Butternut HF2V.
He built one from scratch.
The eham reviews have good feedback from users of this antenna.
I recommend all of the above.
My HF2V modifications .. in a NUTSHELL
1) I moved both coils up from 3 ft off the ground to about 7
ft off the ground. I figured I could still get them to work
with a bit of adjustment. I WAS RIGHT. I had to short out
some turns and play around with it a bit..but it was not all
that hard to get the new HF2V to work on 80 and 40 meters
with decent swr curves.
2) I added some top loading to my vertical. I used a hustler
RM10 coil at the top. (note: I had to short out a few turns
of the upper hf2v coil). Top loading is supposed to be the
most efficent form of loading an antenna.
3) I used thicker larger diameter tubing and the vertical
now flops (whips) around less in the wind. I bought two
brand new pieces of aluminum tubing (6 ft long) and made
up a new larger diameter lower section (below the coils).
4) I used a base insuator and tubing from an old vertical
antenna to make a new base for the antenna.
I used a chunk of railway rail as a heavy base piece and I
can tilt the vertical over easily by loosening 2 hose clamps
on the upper brace bracket. NOTE: DURING THE WINTER
THE INSULATOR GOT STUCK IN ICE AT THE BOTTOM OF
THE ANTENNA AND I forced it too much when trying to
lower the antenna with high winds bothering me and I
broke the base insulator. I built something a little simpler
that works ok. A commercial tilting base like DX
Engineering makes would be a nice addition.
5) An upper brace bracket on a 4 by 4 (at about the 6 ft
level) supports the antenna. I use 2 hose clamps to
secure the vertical at this point
6) where the coils are (at about the 7 ft level) I took a
couple of fiberglass quad spreader arms and some
fiberglass fence stays and made an upper insulator thus
replacing the old hf2v insulator. NOTE: both fiberglass
insulators had been gucked up with conductive
compound so I decided to make new ones.
The old Butternut insulators will be sanded clean and
used for some other antenna project. I could have bought
new insulators but I decided to use some materials that I
had in my junk collection. Fiberglass rod or perhaps some
other strong insulator such as delrin might be a good
If you look closely at the photo below left..you can see the
contaminated insulator. My new insulator is made from 2
concentric pieces of hollow fiberglass quad spreader
material but I inserted some fiberglass fence stays that I
taped together to form a sort of torsion bar suspension.
I want to go out and buy a proper piece of fiberglass rod
about 2 or 3 ft long to make it even stronger. Right now..I
take the antenna down in high winds. ONLY TAKES about
1 minute to raise or lower the antenna to the ground.
The previous owner put conductive paste on an
INSULATOR!!!! --- not a good idea at all. That IS THE EXACT
OPPOSITE OF WHAT WE WANT. I couldn't really get the
insulator clean the way I wanted to..so I made my own
insulating section..lots of photos ON THIS PAGE OF THE
MODIFIED INSULTATOR mid point and the coil assembly
being worked on ..LINK HERE TO THIS PAGE.
UPPER INSULATOR ASSEMBLY: the new insulator
and the coil assembly.
Above: hollow fiberglass tubing one section fit inside another section (double
wall as a result). This is cut from arm material for a Lightning Bolt quad. If you
want even more strength..buy a length from a company such as MGS or one of
the outfits stateside that sells quads and quad parts. Solid Fiberglass rod or
perhaps delron rod.
Above: a closeup of the JUNCTION of the two coils. NICE CLEAN
INSULATORS NOW..SNUG AND SECURE. I have had this antenna up for
almost 2 years now and no problems. I lower it down when it gets very
windy..just for peace of mind. I do have a hydro line going diagonally
through my back yard ..so I take extra care to be on the safe side.
To the left pictured. The new fiberglass insulator is about 2.5 ft long or
maybe 3 ft. Its been a while since I built this assembly down in my
The bottom of the new fiberglass tube insulator goes inside the
aluminum lower tube and hose clamps and the original HF2V clamp hold
things securely together.
The top of the fiberglass insulator is actually out of the picture a wee bit.
The top part of the aluminium tubing goes over the top of the insulator
and is held in place with compression clamps.
RADIALS or counterpoise. Yes
the other half of this antenna
is a bit below the sod. CLICK
HERE TO SEE THE GROUND
WORK and my spider web
approach (small footprint
ground)..it works pretty well
even on 160!! LINK HERE
CLICK HERE GROUND
|HAMelectronics Magazine -- dot com Mar 1-2011)
My HF2V is more rugged. Especially when in gets windy. The
aluminum tubing at the bottom has been replaced by larger
diameter tubing I bought at a ham radio flea market from a
fellow who sells aluminum for antennas. The original tubing
from the HF2V has been moved up the antenna to the top.
The original floppy tubing at the top of the antenna has
been removed completely. I might use it for another project.
Here is the simple fold
over base insulator. I
made it from a piece
of railway rail that I
bought at a yard sale.
The base of the
vertical antenna was
from an old HF vertical
that I had around here.
It worked fine until it
got stuck in the ice
and the plastic
snapped. I tried crazy
glue but it didnt work
well. I might try
mighty putty or I'll try
and buy another
junker vertical with
the same bolt pattern.
|Present Day..maintenance and some more analysis on how it was built (is built!)
Well, its a mild spell here in Northeastern Ontario Feb 16, 2011 and I decide to go out
into the back yard and take down the antenna to snug up some nuts and bolts and as
well..I can take some rough measurements of the antenna in terms of physical
dimensions and materials. I am writing this article up tonight after the fact. In the pic
above, I have leaned a 4 by 6 inch by 8 ft long spruce board against the vertical. To
anyone familiar with the HF2V Butternut/Bencher Vertical..this is a definite significant
modification to the antenna. A 4 by 4 spruce post is a support post for the vertical.
My vertical, with the new pieces of larger diameter aluminum tubing from the base
up is much stronger than the original antenna. I dont guy mine even though it is only
about 15 ft from a hydro line comming from the back of the yard to my home.
I do, however, lower the antenna down in high winds. It only takes about a minute to
loosen 3 hose clamps and lower it down with ease.
From the bottom of the ground to the bottom of the two loading coils,
it measures about 9 ft. When you move a coil up a vertical..the
inductive affect will be less. I added some top loading right near the
top of the vertical in the form of a 15 meter Hustler RM 15 mobile coil.
That compensates for the two main coils being moved up the vertical
My thinking was to improve efficiency of this antenna a wee bit by top
loading and center loading it somewhat. Also..this way..the coils are
up above head level and out of the way and out of the snow ect.
|FUTURE MODIFICATION (this spring 2011) REMOTE TUNING!!
Right now..I tune the swr down to 1.1 to 1 using a tuner in the shack. This antenna
has sharp swr curve on 80 in particular (which is good!)
I want to try an idea.. A TOP HAT THAT ROTATES USING A CHEAP TV ROTOR.
THE top hat would be specially designed to interact with the top HF2V coil in such a
way as to lower resonant point down into the cw band when I want to operate cw.
The "SOME OF THE spokes of the top hat will be bent down and some up. It will take
some experimentation as to the configuration and how far away from the coil the top
hat will be and how the spokes will be "SKEWED" ECT but it should work.
I will be publishing photos in a couple of weeks or months. Right now..we still have a
wee bit of snow in the yard and April has turned out to be a bit too wintery!
IF YOU WANT TO SEE MORE DETAILS AND
PICTURES OF THE MID SECTION COIL AND
INSULATOR THAT I made up (THE MAIN
MODIFICATION I DID TO THIS VERTICAL)..I
MADE A SEPARATE PAGE WITH PICTURES LINK