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By Mark Griffin, N5HII Being a relatively
new ham, my first thoughts were like everyone else, to get on the air as
quickly as possible. It didn't take me long to become frustrated with the
performance of the 1/4 wave mag mount that I bought as a cheap and fast
way of getting out and talking. I thought maybe a 'Hamstick' or something
like it would do a better job for my mobile, but I really wasn't sure what
would be best. I also wanted an antenna for the house, as sitting inside
is infinitely more comfortable than huddling in the truck if it's cold or
rainy. After talking to other hams and searching the net, it seemed like
the next best step for a home rig would be a j-pole, either copper or twin
lead. Well, to make a long story short, I combined the two ideas, and the
"J-Stick" was
born.  First of all, I rummaged through my shed and
located an old Firestik 7' CB antenna that was long lying dormant. I
pulled off and saved the rubber end cap, and then stripped the plastic
covering off, and then spooled off all of the copper windings, leaving a
3/8" fiberglass whip with a 3/8-24 threaded mounting
stud.Next, I
made a standard j-pole antenna out of 300-ohm twin lead. I'm not going to
recount how to do that, as there are dozens of examples on the Web. It's
important to get it tuned for a low SWR, as you'll be modifying it and
need a good known starting point. Check it at 144, 146 and 148 MHz. Once
the antenna and its coax feed line were completed and tuned, I started
I then cut a length of shrink tubing a few inches longer than the whip, and shrunk one end down for about half an inch. This will keep it from sliding all the way down past the tip, because it will be on and off the whip quite a few times. Slide the shrink tubing over the whip, and test the SWR again. You may have to remove a good bit if twin lead to get the SWR back down, it really depends on the shrink tubing you are using. Just like putting one of these j-poles in PVC, the shrink tubing changes the velocity factor of the antenna system. You will have to keep working at it until you reach a SWR minimum that you are happy with. With the j-pole taped to the shaft starting at the top of the stick, the bottom end and the feed point are both more than 1/4 wavelength from the mount, so that parameter is satisfied. Once the SWR is good with
the shrink installed, use a heat gun, hair dryer or a burner on your
kitchen stove to shrink the tubing tight over the j-pole. You don't want
to melt or burn it, so watch it closely. As you get toward the bottom half
of the antenna, start paying attention to the way the coax is routed down
the shaft. You can make it nice and neat by keeping it straight as you
shrink it into place. I trimmed the shrink even with the top of the shaft,
and let it overlap the metal ferrule at the Next, you have to work out the mounting. The
whip is relatively unyielding, so mounting it on the roof was out, as the
cab roof of my truck is about 7' high and the antenna would have hit most
overpasses. Although it is a compromise, I decided on the rear bumper. I
bolted a 1/2" galvanized floor flange to the bumper, and screwed 
Next came a 1/2" threaded coupling, and into that I
installed a stainless steel 1/2" x 1/8-27 NPT reducing bushing. This I
tapped out to 3/8-24 NF machine thread. Although you could screw the whip
straight into this, I chose to use a Hustler QD-2 antenna quick-disconnect
so that I could easily lay the whip down if I needed to get into any low
spots. This arrangement puts the QD-2 right about the height of the top of
my bed, which in turn places the bottom of the antenna element better than
24" from the bed, easily satisfying the 1/4 wave separation requirement
(see 2nd picture below).
 I used a 12' length of coax for this project, so I was able to take 5 turns about 5" in diameter to form an RF choke at the base of the whip (see 3rd picture below).  This really seems to help in keeping stray
RF out of the system. It does look a bit odd, however. The coax is then
coupled to a run of RG-8X up to the transceiver in the cab.
Email Mark for questions ~ n5hii at arrl dot net 
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