Is the XM240's driven element normally grounded or floating? Does the
Ameritron ground unused ports? Do you still get high SWR if the TH7 is the
only antenna connected to the Ameritron?
Just a wild guess, but perhaps the Ameritron is grounding the XM240's driven
element when the TH7 is selected, thus making a nice ground plane 12.5'
above the TH7.
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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