Hi Jake!
I tried this and it worked - sort of...
I have a 60 foot tower gamma-matched for 60, 80 and 160 meters with a
stack of VHF/UHF antennas on the top. Coax lines for the VHF antennas
are tied to one leg of the tower on the inside.
I originally used copper water pipe for the gamma match in the center of
the tower. I could get a good match the VHF coax cables were mega-hot
with RF going into the house. Those cables are in PVC conduit under
ground, under the radials.
Moving the copper water pipe gamma match to the outside of the tower
resulted in more than doubling the radiated field voltage and the VHF
coax cables are now free of the 60-80-160 RF.
Relative radiation efficiency voltage was measured at the end of my
driveway, about 240 feet away - you can see the layout on Google Maps,
Satellite View. You can see the gamma matched tower on my QRZ page.
73
Lloyd - N9LB
On Wed, Oct 31, 2012 at 12:19 PM, jcjacobsen@q.com wrote:
How do to all,
I have a hypoth--er hipoth--oh, alright, a theory, question for all.
Take a grounded, 1/4 wave vertical (pick your band/freq of interest)
made of tower sections. You're going to feed it with a gamma match.
Could the gamma match rod go on the inside of the tower sections for
protection?? And, yes, I know, you could insulate the tower from
ground and series feed it. BUT, after all this is a hypoth....er
hipoth....theory question.
73 es GDDX.
K9WN Jake _______________________________________________
Topband reflector - topband@contesting.com
_______________________________________________
Topband reflector - topband@contesting.com
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