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[TowerTalk] remote control of antenna switch via "wired" UHF

To: TowerTalk <>
Subject: [TowerTalk] remote control of antenna switch via "wired" UHF
From: Pete Smith <>
Date: Sun, 01 Jan 2012 10:18:29 -0500
List-post: <">>
I am planning to build, in the next couple of days, the couplers needed 
to test this idea.  To revisit it, I have qn inexpensive RF-controlled 
8-way band switch, and several people suggested that I should couple the 
RF from the "remote" to my feedline, and pick it off the other end, to 
eliminate path losses over the ~300 foot range.

This seems plausible to me, but as usual I'm having trouble figuring out 
the specifics.  Say I take a piece of RG-59, remove the jacket and the 
shield braid, and then couple the output from the remote to the center 
conductor moni-match style.  Should I lay the coupling wire parallel to 
the center conductor, or should I wind it around the insulated center 
conductor?  What sort of total length for the coupling wire would give 
best results at ~315 MHz?  Any difference in the design of the coupler 
on the receiving end?

I assume I should pull the braid back over the "coupler" section - is 
that right?  If I have common mode chokes (#31 toroids) on both ends of 
the feedline, will it be better to have the couplers between the chokes, 
or doesn't it matter, since the UHF RF will presumably be going by 
differential mode?

73, Pete N4ZR

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