At 01:42 PM 8/23/98 -0500, Ron Feutz wrote:
>
>My present L is 1/4 wave, 85' vertical run. I want to raise the current
>loop to the center of the vertical section and increase the radiation
>resistance. I have a 1000pf "breadslicer" available. Can I simply add
>45' of total length to the wire and put the capacitor in series? Please
>reply directly to me.
>
>WA9IRV-Ron
Been doing just that for years.
Since most Inverted L's have Zo of around 15 to 30 ohms at
resonance(depending on height of the L and the effectiveness of your
ground). Lengthen the antenna till the R portion of R+jX reaches 50 ohms
then tune out the jX component with the series cap (-jX) has been done for
years.
Lots of arguments that It will likely not buy you much in signal strength
improvement. direct your flames some where else guys on that issue. I'm not
getting into either side of that debate which has been about as emotional
as elevated versus buried radials~8^).
It sure makes "tunning" the antenna a snap though. In fact if you put a
small motor on the capacitor shaft and move the resonance of the antenna
anywhere in the band you want to operate remotely from the shack. I have
all the pieces to do just that and maybe will get around to it this winter.
Dave K9NX
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