I agree with Jim as I ran into the same problem at work. Twelve story office
building with a copper roof. Any two meter transmission at that building roof
area over two Watts and intermod products would cause problems in other VHF
repeaters several blocks away. Our solution was split site, with the TX on
another 12 story plus engineering floor on top.
Bonding the roof can be done... the problem is dissimilar metals in the roof
panels and fasteners plus lack of a sealant to keep the screw - panel junction
dry. There is another way to fix the problem... slate or tile roof heavy enough
to resist the wind problem.
73,
Gary ~ AB9M
Sent via the Samsung Galaxy Tab® 3 Lite
-------- Original message --------
From: Jim Brown
Date:01/11/2018 1:00 PM (GMT-06:00)
To: towertalk@contesting.com
Subject: Re: [TowerTalk] Metal Roof
Hi Skip,
The "interference" is probably passive intermod (rectification at one or
more joints in that roof) that is generating a spur on the input
frequency of the repeater. If this is the cause, the joint(s) must be
bonded at multiple points.
73, Jim K9YC
On 1/11/2018 10:29 AM, Gilbert Kauffmann wrote:
> My repeater is desensed.
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