Hi guys,
I plan to homebrew a combination 80-40 meter vertical to place at the edge of
a saltwater river. I am thinking of using one of the following options.
Your thoughts would be greatly appreciated.
OPTION 1: Use a 33' tower and extend a 33' length of aluminum tubing out of
the top section giving a combined height of aprx. 66'. I could insulate the
tower from ground and base feed it giving me a 1/4 wave on 80 and a 1/2 wave on
40. I would then need to match the base impedence for 40 meters. What would
you recommend for matching the impedence?
OPTION 2: Use the same 66' structure as listed in Option 1 but ground mount
the tower. Have 2 shunt feed systems: one for 40 and one for 80. Can I have 2
shunt feed connected at the same time?
OPTION 3: Use the same 66' structure as in Option 1 but not only insulate the
tower from ground but isolate the top 32' section from the bottom. This
would give me a 1/2 wave vertical dipole on 40. When used for 80 meters I
would
use a relay to connect the lower and upper halves giving me a 1/4 on 80. What
would you recommend I use to switch in/out the two sections?
Ideally, I would like it set up for fast band changes. (no time to fool
around outside during a contest!)
Any recommendations at to which option would provide the best field strength,
bandwidth, easiest match, etc. etc. etc. is much appreciated!
73, Dick- K9OM
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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