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Re: [TowerTalk] mystery tool and damaged 40m antennas

To: "K1TTT" <K1TTT@ARRL.NET>, "reflector -tower" <towertalk@contesting.com>, "reflector cq-contest" <CQ-Contest@Contesting.COM>, "YCCC" <yccc@yccc.org>, "Rlx" <RLX@yahoogroups.com>, "Nobarc" <nobarc@nobarc.org>
Subject: Re: [TowerTalk] mystery tool and damaged 40m antennas
From: "Dubovsky, George" <George.Dubovsky@andrew.com>
Date: Fri, 4 Apr 2008 09:36:02 -0400
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
It's a can and bottle opener, commonly given away at paint stores.

73,

geo - n4ua

> -----Original Message-----
> From: towertalk-bounces@contesting.com [mailto:towertalk-
> bounces@contesting.com] On Behalf Of K1TTT
> Sent: Friday, April 04, 2008 9:38 AM
> To: reflector -tower; reflector cq-contest; YCCC; Rlx; Nobarc
> Subject: [TowerTalk] mystery tool and damaged 40m antennas
> 
> Take a look at the picture of the tool next to a pencil for size
> comparison:
> http://www.k1ttt.net/images/2008_40m4lldd_repair_1.jpg
> 
> This tool was uniquely suited for one particular job while
disassembling
> an
> ice and wind damaged 40m4lldd yagi.  Out of all the tools in all my
> various
> tool boxes this one stood out for this one specific task.
> 
> Can you identify:
> 1. What it's original purpose(s) were?
> 2. What it would be used for in a 40m yagi disassembly?
> 
> 
> Pictures of the 40m damage in progress are below... We had 3 ice
storms in
> 2
> weeks, 2 of them were followed immediately by strong winds.  Besides
> damage
> to both 40m4lldd's there were several bent elements on 20m4dx yagis
that
> had
> survived several years with 'normal' ice and wind.  Something
interesting
> to
> note is that the loading rods on the 40m4lldd's did not provide any
> mechanical strength to the elements even though they look like they
would
> act as trusses.  The elements all bent on the same side of the
antennas
> because the wind hit them from the side while the element was already
bent
> down under the ice load.  The same mechanism damaged all 4 elements of
the
> top fixed European 20m yagi that was sideways to the wind, while the
> rotatable one above it only had 1 slightly bent element since it was
> pointing into the NW wind at the time.  The loading rods broke all on
the
> same side because the wind shifted while the elements were bent so one
> side
> of the loading section was stretched against the side of the element.
> 
> Tower is 180' of Rohn-55 with the 40m4lldd's on ring rotors at 70' and
> 170'.
> 
> 2/2 Top 40m with ice and wind
> http://www.k1ttt.net/images/2008_feb_02_40m_ice_1.jpg
> 
> 2/2 Top 40m with ice, note how on the left side all 4 elements are
bent at
> the sme place and the loading rods are below the element tubing.
> http://www.k1ttt.net/images/2008_feb_02_40m_ice_2.jpg
> 
> 2/2 Top 40m with ice element closeup
> http://www.k1ttt.net/images/2008_feb_02_40m_ice_3.jpg
> 
> 2/2 Bottom 40m with ice
> http://www.k1ttt.net/images/2008_feb_02_40m_ice_5.jpg
> 
> 2/7 Top 40m with ice and wind, round 2 of the storms you can see the
1st
> loading rod broke on the right element.  Eventually all 4 elements
ended
> up
> with 1 broken rod, all on the same side.
> http://www.k1ttt.net/images/2008_feb_07_40m_ice_11.jpg
> 
> 2/7 Top 40m with ice and wind, slightly crooked elements.
> http://www.k1ttt.net/images/2008_feb_07_40m_ice_13.jpg
> 
> 2/7 Top 40m broken loading rod closeup
> http://www.k1ttt.net/images/2008_feb_07_40m_ice_8.jpg
> 
> Removal of the damaged antennas was done by XX-Towers on 3/7:
> Rigging bottom 40m, tram line is cable coming down to left.
> http://www.k1ttt.net/images/2008_mar_07_kc1xx_2.jpg
> 
> Bottom one coming down
> http://www.k1ttt.net/images/2008_mar_07_kc1xx_4.jpg
> 
> Bottom one wide view
> http://www.k1ttt.net/images/2008_mar_07_kc1xx_5.jpg
> 
> Closeup of broke loading rod end, its really not pulled out, the
shorting
> bar held and the rod broke.  The ss saddle and eye arrangement on the
> philly
> cable is my modification to prevent the philly from being cut on the
side
> of
> the small holes it used to go through on the shorting block.  M2 has
> modified the design with a strain relief to prevent that on new ones.
> http://www.k1ttt.net/images/2008_mar_07_kc1xx_6.jpg
> 
> Rigging the top 40m, tram line is hard to see but comes down between
guy
> wires toward bottom.
> http://www.k1ttt.net/images/2008_mar_07_kc1xx_7.jpg
> 
> Rigging top, wide view.
> http://www.k1ttt.net/images/2008_mar_07_kc1xx_8.jpg
> 
> Liftoff of top one.
> http://www.k1ttt.net/images/2008_mar_07_kc1xx_10.jpg
> 
> Top one starting down
> http://www.k1ttt.net/images/2008_mar_07_kc1xx_12.jpg
> 
> Interesting rigging, use ring rotor supports and boom brace to spread
load
> to 4 points on boom.
> http://www.k1ttt.net/images/2008_mar_07_kc1xx_13.jpg
> 
> Insurance has already paid off and I am awaiting delivery of a new
125mph
> 40m4lldd for the top.  For the bottom one I salvaged parts from the
top
> one
> to make it whole and have purchased aluminum to beef it up similar to
how
> the 125mph elements are done.  I also am waiting delivery of a 20m4dx
to
> be
> used for parts to replace bent element sections on those antennas.
> 
> Of course I am writing this today because we are now getting
snow/freezing
> rain/rain/whatever out there and I figured I can wait a while to
continue
> repairs.
> 
> David Robbins K1TTT
> e-mail: mailto:k1ttt@arrl.net
> web: http://www.k1ttt.net
> AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
> 
> 
> 
> 
> _______________________________________________
> 
> 
> 
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
> 


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