[TowerTalk] Attaching junction box to tower?

w8ji.tom w8ji.tom@MCIONE.com
Wed, 11 Nov 1998 13:38:54 -0500

Hi Jim,

> My boxes are attached to both towers with no problem after almost 17
> of operation.  If there were problems, I would add a choke to the control
> cables using a core.

I can't imagine running Beverages up to a tower, and expecting them to
work, for a number of reasons.

1.) The tower re-radiates signals.

2.) The Beverages all couple to each other when grounded to a common point,
and you can be sure the tower will be "pumping" the ground up and down in
voltage around the tower unless it has an absolutely perfect ground system.

3.) The Beverage end impedance is several hundred ohms, aggravating
electric field coupling from the Beverages to other conductors and
Beverages. Bringing those antennas to a common point is a bad enough idea
when they are NOT near a tall tower.

You may have gotten away with it for 17 years, but I have repeatedly seen
interaction between my Beverages and antennas (towers) that were hundreds
of feet away. IMO, the Beverages and the switching box belong as far from
the tower as possible, there isn't a choke in the world that will fix the
problems that occur.

73 Tom

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