[TowerTalk] Bird loading and elements

[AA6DX - Mark]

OH OH .. here come the Rettysnitch owl again!  Use the Wolf Hong to insure 
that the is bird is properly aligned with Polaris!  =|;?}  (Bet you wondered 
all these years what those vile instruments were used for in the REAL 
world!)
Mark  AA6DX
----- Original Message ----- 
From: "Pete Smith" <n4zr at contesting.com>
To: "SJ W3TX" <superberthaguy at adelphia.net>; "David Robbins K1TTT" 
<k1ttt at arrl.net>; "'TowerTalk'" <towertalk at contesting.com>
Sent: Wednesday, May 04, 2005 2:43 AM
Subject: [TowerTalk] Bird loading and elements


> Interesting story about birds breaking a reflector tip.  During the spring
> and fall, I often have so many small migrating birds on my Force 12 
> EF-240S
> that they are literally shoulder to shoulder.  The elements bend
> dramatically, but always spring back.  Occasionally some hawks or turkey
> buzzards will perch on the antenna, but they wisely do not attempt it out
> at the tips, preferring the boom instead.
>
> I'm a little surprised that birds that would try to perch on an element 
> tip
> would be so heavy as to break it.
>
> 73, Pete N4ZR
>
> At 10:42 PM 5/3/2005, SJ W3TX wrote:
>
>>I have seven M2 monobanders up.
>>
>>Everything has held up well since 1999!  Their designs and QC and customer
>>service have been excellent.
>>
>>I've had two mechanical failures...both were acts of nature that NO design
>>could survive.
>>
>>The first was when a chunck of ice fell off the 40m3 at 120ft and hit a
>>director on the 10m7 at 35 feet.  I'm glad it hit the element and not a
>>person or pet!
>>
>>The second was when a flock of birds roosted on the 40m3 reflector 
>>creating
>>a force that exceeded the elasticity modulus of the aluminum tip section.
>>The birds were a little surprised, but none got hurt (if they had I could
>>fix the birds...I'm a vet).
>>
>>The birds were back the next day (and every day since) testing the 
>>antennas
>>again...so far the antennas are fine!  With 41 elements on one pole, all 
>>the
>>roosting activity, and the inevitable bird droppings I'm starting to 
>>wonder
>>if I can pay for this hobby by starting a guano factory?  Maybe I need 
>>more
>>elements!!
>>
>>I like the M2 yagi so much I ordered more for future use.
>>
>>73, Scott W3TX