Atlanticon 2003
QRP Forum Speaker
James Bennett, KA5DVS
"Practical and Portable Antennas"
For those QRPers who have been
living a sheltered life, KA5DVS is the designer of the award-winning PAC-12
portable antenna introduced last year. His fabulously-simple and efficient
portable antenna design took top honors in the HF Pack "antenna
shootout" in 2002, and was chronicled in a feature article in QRP
Homebrewer #8 over the summer. (The project and article was so
exciting and popular that it was also made fully available online at http://www.njqrp.club/pac-12).
See the "About James" section below, as it tells so much more of what
drives him to the creative designs he's given to our QRP and antenna
communities.
I recently had dinner with James and his wonder wife Kathy and he was sharing
many ideas he's got queued up for presenting at this year's Atlanticon.
What a wonderful treat we are all going to be in for! There will be a
surprise long the way too, so you really want to get in on this when it
originates at the Atlanticon weekend. To quote James ... "I am always
fascinated that the small amount of power our QRP radios produce can even be
detected, much less carry information. To me, it is still magic that a
radio with some metal and wire can send a signal to far parts of the globe, and
to do this with low power and an antenna that I have built never ceases to
fascinate me."
It is this fascination that drives James to experiment with many different
materials and portable designs, and it is this same fascination that will
delight and entertain QRPers attending Atlanticon this year!
About James Bennett,
KA5DVS ...
I was first licensed in 1979 while in high school in Arkansas and today have an
Advanced class license still with that original callsign. I started in ham
radio when I asked one of the teachers what all the antennas on his car were
used for. Within a year, I had my novice license. My first contact was with a 8
call area station and I was pretty nervous. From an early age, I was
always interested in radio communications. I received a pair of walkie
talkies that operated on 27Mhz. Not being happy with the 1/4 mile or so
range the small antennas gave, I soon built a base station and bicycle antenna
using copper wire wrapped around fiberglass bicycle flag poles. I managed
to use somewhere around a half wave of wire and the antennas worked well.
I was able to maintain communication with my brother at home up to about 1 miles
away from by bike. Since the walkie talkies were low power, I was
also doing QRP without knowing it.
Once I got my ham license, and got my first radio (Heathkit HW 16), I needed
antennas. Living in the hills of northwest Arkansas, antenna parts were
not the easiest to find. I ended up building a fan dipole for 40 and 80M
using #14 copper wire and PVC fittings for insulators. The antenna got me
on 80, 40 and 15M and produced many enjoyable QSOs. I eventually traded
up to a Drake TR4C and adapted a 10 and 15M groundplane vertical using plans
from QST. I also experimented with other vertical designs with varying
degrees of success.
I earned a BS and MS degrees in Physics from Hendrix College in Conway Arkansas
and the Univ. of Arkansas, Fayetteville respectively. During college, I lost
interest in radio and it wasn't until I was attending graduate school that I
rekindled my interest. I learned of the U of A club station, W5YM and was
soon a member of the club. The club station was across the street from the
physics building and I would operate late at night for a break. During
this time, I converted a CB board to 10M FM and had lots of fun making contacts.
Ham radio took a back seat when I went to NJ for my first job moved into a small
apartment. I did build a couple of the Ramsey kits and put up an indoor dipole
but it saw very little use. When we bought our house in Hightstown, NJ, I
finally had a basement for a shack and yard space for antennas. I also
picked up a Yaesu FT301S at a local hamfest to get back on the air. I
first put up a simple loop antenna for 40M and up and used it for a while.
However, I have always liked vertical antennas and soon I began on a design. I
ended up using 30' of copper tubing which I painted green to blend in with the
spruce trees in my back yard. I build a relay switched tuning network at
the base and I was soon on the air on all bands. About this time, I also
discovered QRP-L on the internet and found that there was a small group of
QRPers that met in the central New Jersey area. I attended a meeting and became
member #9 of the New Jersey QRP Club. Ham radio began to be a lot more fun
than it had ever been and the rest, as they say, is history.
Over the years, I have always enjoyed designing and building antennas.
Some might say I am cheap and they are probably correct. However, I find
it a challenge to go into a hardware store and come out with parts to build an
antenna. I also find satisfaction making contacts with an antenna built
from scratch. I've always favored vertical antennas as they can be fit
into smaller space and don't require tall supports to work well.
The PAC-12 antenna was another example of an antenna born of a need. In
1997, I moved to California to join a startup company. The company grew
and I soon found myself traveling quite a bit on business. I build a K2
and took it along on many trips. I used dipoles and random wires but the
lack of supports in some locations led me to look to a self supporting design.
Once again, I was cheap and decided to build a travel vertical antenna. I
browsed the local Home Depot and eventually ended up with PVC and aluminum rods.
This, along with a 72" whip from Radio Shack, became my travel antenna.
It went through several iterations eventually ending up as 12" sections for
easy portability. I chose to make it center loaded to improve efficiency.
Along the way, I bought a Yaesu FT817 for travel and it has accompanied me on
many trips with my antenna.
Today, I continue to work on several portable antenna designs with the goal of
optimal efficiency, minimal weight and portability.
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