Homebrew 2 Meter Onmi-Antenna
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     Here is a simple 2 meter antenna that works great! I have
found that the antenna has somewhere around 3 dbi of gain. This
comes from some rough calculations and testing. Don't hold me to
this however.

     First you will need the following items:

     1. Aluminum tubing. I used some tubing from an old antenna.
          3/4 inch works fine for the base or what ever you have
          laying around.

     2. Some #10 gauge copper wire.

     3. PVC coupling to match the dia of the tubing you are using.

     4. 1 259 female box connector

     5. A couple of wire ties

     6. 2 hose clamps.


     Start by constructing a 5"dia. ring from the #10 copper wire.
This I did by using an old propane bottle as a form. Wind the wire
around the form so that there is a two inch overlap of the wire.
Then strip the insulation from the wire, do not strip the two inch
overlap ( This must remain insulated ). Using two wire ties clamp
the two inch overlap together, forming a capacitor. Now bend the
tag ends so that they go to the center of the circle. These must
attach to the antenna so that the antenna is in the center of the
ring!

     Next construct the antenna by cutting a 48" inch long piece of
the tubing, and a 24"inch section. These two sections connect to
each other by@using the PVC coupling. I was able to ram the
aluminum tubing into the PVC coupling needing no additional
fasteners. However you could put a screw of two through the couple
to help hold the section together if you wish.

      Next connect the 5" ring to the main antenna so that the
antenna is centered in the ring and directly over the PVC coupling.
One end of the ring must connect to the ground side and the other
to the mast. This I did by using a couple of self tapping screws,
and bending the tag ends so that I had a small eye to place the
screws through.

     Next I constructed an angle bracket using some copper tubing
(1/2 inch) about 4"long.  I beat it flat (This is good for stress
relief). Once flat I bent a 90 degree angle so that I had about
1 1/2 inch to but the 259 connecter into.  Drilled a hole in this
piece so that the 259 box connecter would fit and  soldered it
into place.  This then connects to the ground side of the antenna
using some hose clamps.  Then solder a piece of #10 copper wire to
the center of the connecter and bend a 90 degree angle in it so the
wire touches some where on the ring.  I found that a good place to
start is approximately 1.5 inches from the capacitor.

     TUNING: To tune the antenna for best swr is a simple process.
Just loosen the hose clamps holding the coax connecter and adjust
it around the base of the antenna so that the feed point on the
ring changes. Once you have established a 1:1 swr  at the desired
frequency solder the feed point wire to the ring.

Enjoy  Chuck N0YSR @N0YSR.#NEKS.KS.USA.NOAM