Mike Waters W0BTU wrote:
> I have some trees picked out for a T antenna, between a section of pasture
> where it's easy to lay down a lot of radials. I can have a 50' vertical
> section.
>
> But I'm having trouble finding what the approx. dimension of the horizontal
> portion at the top should be. Any advice would be appreciated!
>
>
Mike, Assuming a 50 foot vertical drop...... 100 foot horizontal section
or more to make the feed point have some inductive reactance which you
can tune out with a series cap to get a reasonable VSWR. If you have an
MFJ 259B you can check the base impedance and reactance right at the
bottom of the drop and put in a fixed mica transmitting cap close in
value to the inductive reactance you read. Or use a bread slicer to see
what you may require and replace with a fixed cap after measurement You
might also want to use a choke to decouple the feedline run from the
vertical T. If you can drive the base impedance up to 40-50 ohms by
adjusting the equal length of the top.
See you in the contest.
Herb, KV4FZ
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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