Topband: matching the L

[Lane Zeitler]

I finally have the elevated inverted-L near final completion. The feed =
point is 15 feet off of the ground. From there it is vertical 60 feet =
and then out horizonal another 75 feet for an overall length of 135 =
feet. The end of the horizonal section is currently only 30 feet off of =
the ground but will worry abt that later. The ground plane consists of =
20 radials that are all about 50 feet long and four that are 100 feet =
long. All elevated off of the ground. The pattern is spoked out from the =
base. My lot is 66 feet by 150 feet so the longer ones are zig zagged =
here and there. Eventually I want to put in at least six more 100 =
footers. The antenna is resonant around 1740 khz or so. My analyzer does =
not go quite that low but it is around there.

I want to remote match this thing to cover the whole band. I am looking =
for suggestions. I prefer not to go with motorized caps and would rather =
go with a relay switched network of LC networks. I wonder how many LC =
networks I would need to cover the whole band? I would like to keep the =
VSWR under 1.5:1 so I am curious if I could get away with maybe five or =
six remotely switched networks?

What voltage rating should I use for the capacitor? I have boxes of =
bread slicers around the 4500 volt spacing. Can I go with just one cap =
and then just select different taps on the coil?

I have also considered just feeding it with open wire line and bringing =
that into the shack into the HB roller inductor tuner but I am afraid I =
will get feedline radiation. Right now feeding it with 50 ohm coax at =
the base and bringing that into the shack into the tuner I have ZERO =
emi/rfi/tvi even when running a KW. It tunes up great on 40 and 80. It =
is a bit harder to tune on 160 but it does tune down to 1.1:1 on =
topband.

Suggestions welcome.  Please reply direct.

Lane
Ku7i
San Diego



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