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Simple 2 Meter Ground Plane Antenna
Project
With PVC Support
by
KC0YNR,
Malcolm
Here is a very simple 2 Meter Ground Plane project
that can be used as an emergency antenna, in limited space, for quick and
easy setup on field day, camping, or just plain outdoor
fun.
With a bit of beefing up, it would make an
excellent starter antenna for just about anyone on a shoe string
budget!
Got some old solid copper wire laying around, an
SO239,
a few odds and ends of PVC and a little time?
NO!
Then spend about $10.00 bucks of the XYL's mad money but don't tell
here where it went!
Then you're half done
already!
***********
I built this about a week after I got my ham license.
I needed
a good 2M antenna to hit the Callaway Amateur Radio League
(CARL) club's repeater,
about 5 miles away and found the 2 M ground plane project.
This is
about a 1-hour project, or maybe a little extra to check SWR and trim the
wires to the correct length.
I
started with #4 bolts and stop nuts; #12 wire with insulation stripped
off.
I put a little bend in the ground plane wires to
attach them to the SO239.
The vertical is soldered onto an SO239. The
ground plane wires are attached with #4 bolts and stop nuts. (Partially
assembled with only 2 ground plane wires so I can take photos
easier)
I cut the wires about an inch or so longer
than needed to allow for trimming. The vertical will end up being about
19+" and the ground plane wires 20+" as shown in the original
article.
I
made a mounting cap out of 1" threaded PVC.
I used a 1/4" drill bit
for a pilot hole and a 5/8" spade bit to open the hole for the SO239.
This is how it all goes together.
SO239 mounted in the cap.
The PL259
holds everything in place once it is tightened. Not much extra room in
that cap. I had to use needle nose pliers to tighten the PL259.
All
ground plane wires are now in place.
Finished assembly on 1" PVC.
The threaded cap allows for
disassembly and maintenance. A 2ft piece of PVC is attached at the
coupling and on the other end, a T is attached with the
feed
line coming out of the T.
I just stick this on top of a mast. See
picture below.
Not
quite done yet, but this is what it looks like.
I used a T fitting to
get the feed line out of the PVC and over to my shack.
Just need to
check the SWR and trim the wires to length.
The angle is
deceptive. It's only 12ft high.
Assembled antenna with "custom movable mount".
Standard hillbilly engineering straight out of the
Ozarks!
All that's left is to trim the wires
using an SWR meter until you get good resonance. Trim just enough length
off wires to get good resonance, or you will have to start over.
I
got 1:1 SWR all across the 2M band. Almost no needle deflection on
reflected power.
I'm hitting my repeater nicely with 5 watts despite
my location. There are obstacles about 40ft-50ft higher than me between
here and the repeater. I just move the ladder around to find a good spot.
Next version will be made out of welding rod, and should be sturdy
enough to mount it on the roof where it will take some wind and weather. A
more sturdy version might work as a mobile or portable. Leave off
the mast and mount the short PVC length to your balcony
railing!
This is an easy project for a new ham. About $10 in
parts.
This antenna has no gain but with 1:1
SWR and proper trimming of wires is very resonant across the entire 2M
band.
73s
KC0YNR
Malcolm,
central Missouri
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