This topic has been kicked around so much, I feel like it fits into the
upcoming spring/summer TV reruns. I currently have a G5RV in an inverted Vee
configuration, with the apex at about 35 feet. It works OK on 75/80, pretty
well on 40, OK on 20 and OK on 17. It is a miserable failure everywhere
else. I'm limited in space and height, but after surveying my trees and lot,
I could put up a 135 foot center fed doublet with the apex at about 40 feet
and the ends sloping down to about 15 feet (another inverted Vee, best I can
do with my trees). I would feed it with 450 ohm ladder line to the shack,
mate it with a 4:1 current balun and then connect with a short piece of coax
to my TS450's ATU. Seems like it should work, but I guess I need to ask some
questions:
1) My G5RV is old, and has been patched. I expect it to not survive another
winter or the vinyl eating squirrels. Does the doublet offer me any
improvements? The ladder line would be away from the hungry rodents, free
swinging and not near their trees.
2) Or, should I just rebuild the G5RV and scrape the doublet idea?
3) Is the 4:1 balun a good idea? Seems the only good way to be able to use
the Kenwood's ATU. The G5RV and Kenwood work well together on all bands,
even though it doesn't radiate out of my backyard on some of them.
4) Should I be concerned with RF in the shack with the doublet scenario?
5) Is there a better doublet length than 135 feet? That seems to be the most
common length I see.
6) My intention is to replace the RV with something better, that offers
improved performance on 75/80,40,30,20 and 17. Is it LIKELY this setup will
work, or am I too optimistic? I have an Alpha Delta DXEE which would be
moved to where the G5RV is now, offering me 20,15 and 10 (it's bad on 40).
7) I've spent a bit of time looking over my situation, and this is maybe the
best wire antenna installation I can come up with. I've also considered
making my own 'Carolina Windom', but from what I've read it doesn't offer me
much improvement. Does it? Might the 'Carolina Windom' approach be a better
idea?
My goal is to keep the replacement costs below $35, which I know I can do
with the doublet or the homebrew 'Carolina Windom'. I'm in no hurry, got all
summer to do this and I am retired. I just want to do what will give me the
best results. I'm looking for opinions, suggestions and practical experience
with using one of these doublet/balun antennas or 'Carolina Windoms' and the
kind of ATU found in most modern transceivers. I don't want the hassle or
expense of an external antenna tuner.
Thanks...and 73's from Cicada humming SW Ohio
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Jim & Pat Leder
http://home.fuse.net/k8cxm
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