Thanks for all the helpful suggestions, guys. It seems a common question
was raised, that the LP design impdance is not 50 ohms, and the root of my
problem. I assumed 50 ohms due to the origially specified BN 86 balun,
which I believe is a 1:1 balun, therefore was not hesitant to build a 1:1
choke balun when the the BN-86 flamed out. But I may be wrong, and will
consult the LP 1017 manual, which has the precise measurements and spacing
of the aluminum tubing used for the transmission line down the boom.
Then, using the standard formula for parallel wire impedance, will make a
determination of the design characteristic impedance of the transmission
line... Some wondered about the physical construction of matching section
at the end of the boom, connecting the two end elements.
Here is a picture (also look at http://www.vcr.com/n6ij for more
pictures)
^
^ (front of LP)
^
Transmission Line (follows boom)
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|____________________|
(this section is about 12 ft long, 5/8"
tubing, connected to each half-element at
abt 6 ft from the center terminals, and
spaced abt 8" below the end, (last) half-elements
73, DX de Pat, AA6EG/N6IJ
"The Contest Station from the Government"
Marina Amateur Radio Contest Station; N6IJ
599 DX Drive
Marina CA 93933
aa6eg@tmx.com
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