Hi Terry,
Well -- you ask an excellent question. I have a lot more knowledge now than
I did when I installed the first tower and 6M antenna about 12 years ago.
That said, I have never had any lightning issues although my protection is
not optimized at all.
You are correct that the coaxes come through the roof, into the attic, down
the back of a 2nd floor closet, and into my shack on the 1st floor. Both
towers are tied together and I have "ground cables" coming down both sides
of the house to ground rods on each side of the house. The single point
shack ground is a copper bar connected through the shack wall to one set of
these ground rods. All equipment and the AL plate the coax switches are on
are grounded to this bar in a star pattern. All coaxes not in use are
grounded, and when I am not at home they are disconnected.
What really should be added -- "polyphasers" would give additional
protection, although I don't know where they would work best given the path
the coax takes. With hindsight, I should have brought the coaxes down the
outside of the house to ground level, through a grounded box full of
"polyphasers", and then into the shack. Over the next few years I am moving
my station to a house on Casco Bay in Maine and the design will incorporate
my new knowledge.
73,
Larry
W1DYJ
----- Original Message -----
From: "Terry" <terry@kk6t.com>
To: "Larry Banks" <larryb.w1dyj@verizon.net>; <TowerTalk@contesting.com>
Sent: Monday, March 16, 2009 2:21 PM
Subject: Re: [TowerTalk] roof mount Tripod
> Very nice pictures and diagrams. Looking at both, it looks like the coax
> comes down through the roof and attic and then into the shack. What do
> you do about grounding/lightning protection?
>
> 73 de Terry KK6T
>
> Larry Banks wrote:
>> Hi Bruce,
>>
>> I use two 6' roof towers from IIX Engineering -- don't know if he still
>> makes them, but they also have a rotator plate. One holds my 5 el 10M
>> yagi and my 2 el 20M Moxon -- uses a G-800S rotator. The other holds my
>> 7 el 6M yagi, my 11 el 2M FM yagi, and my 12 el 2M SSB yagi, with an old
>> Alliance rotator. Neither uses a thrust bearing, both have been fine for
>> 5+ years. Check out my web site for pictures.
>>
>> 73,
>> ______________________________
>>
>> Larry Banks FN42kl W1DYJ
>> Amateur Extra ARRL
>> WAS WAC VUCC
>> QCWA 1010 SMIRK
>> MMRA N.E.W.S. MARA
>> larryb@alum.mit.edu
>> http://www.qsl.net/w1dyj/
>> ______________________________
>>
>>
>>
>> ----- Original Message -----
>> From: "Steve Katz" <stevek@jmr.com>
>> To: "W8HW" <w8hw@att.net>; <towertalk@contesting.com>
>> Sent: Friday, March 13, 2009 4:48 PM
>> Subject: Re: [TowerTalk] roof mount Tripod
>>
>>
>>
>>> Glenn Martin Engineering (GME) sells four-legged roof towers from "very
>>> short" to quite tall. They are all made of extruded aluminum and easy
>>> to assemble but very strong. They all have a "rotator plate" in them,
>>> as part of the standard design. The plate accommodates Hy-Gain and
>>> Yaesu rotators (all bell housing designs) and mounts inside the roof
>>> towers, even their shortest one. They all have an upper bracket
>>> directly above the rotator mount where a thrust bearing can be
>>> installed, and they sell the bearings as well.
>>>
>>> I've used several of these over many years at different locations, and
>>> they're good.
>>>
>>> WB2WIK/6
>>>
>>> -----Original Message-----
>>> From: towertalk-bounces@contesting.com
>>> [mailto:towertalk-bounces@contesting.com]On Behalf Of W8HW
>>> Sent: Friday, March 13, 2009 1:33 PM
>>> To: towertalk@contesting.com
>>> Subject: [TowerTalk] roof mount Tripod
>>>
>>>
>>> Has anyone ever tried to mount a Rotor with a ratable antenna on a roof
>>> mount Tripod? If so, how did you Mount rotor and thrust Bering? What
>>> type of tripod did you buy?
>>>
>>> thanks, Bruce, W8HW
>>> _______________________________________________
>>>
>>>
>>>
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>>> http://lists.contesting.com/mailman/listinfo/towertalk
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>>>
>>>
>>>
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>>
>> _______________________________________________
>>
>>
>>
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>>
>>
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