Sent from my iPhone
Begin forwarded message:
> From: Edward McCann <edwmccann@yahoo.com>
> Date: August 11, 2016 at 10:15:01 PM PDT
> To: "Wes Attaway (N5WA)" <wesattaway@bellsouth.net>, towetalk@contesting.com
> Cc: "Roger (K8RI) on TT" <K8RI-on-TowerTalk@tm.net>, edward mccann
> <edwmccann@aol.com>
> Subject: Re: [TowerTalk] Weight on ends of various suspension systems
>
> From Ed McCann AG6CX
>
> I've used the first rope over the branch as halyard for years. But into that
> first line I tie a plastic covered steel bicycle locking cable (Home Depot --
> -$10)
>
> http://www.googleadservices.com/pagead/aclk?sa=L&ai=DChcSEwjeurS8jLvOAhVRk34KHY81CbAYABAO&ohost=www.google.com&cid=CAASJORovDu1in9IvldshDLunFbGTd1nm7MaHfd3Vr234cm8NXyQlA&sig=AOD64_0ow8vIuUS_MsHTFouTCy1WWSnPOQ&ctype=46&q=&ved=0ahUKEwjKvLG8jLvOAhUK9GMKHW86AIIQzzkIJQ&adurl=
>
> that rides on the tree limb or in the limb crotch. To each steel eye I attach
> a stainless link of appropriate size, attach a 3/16" dacron line making a
> continuous loop. Marine block attached to highest end of bike cable, thru
> this block goes the antenna rope, outboard end in insulator with bowline,
> wire from other side of insulator outbound to the other tree. Tree one holds
> halyard with wear-free plastic covered steel cable, and both ends of what
> becomes the antenna wire lead.
>
> Secure both halyard ends at tree bottom with cleat into tree, rope end of
> antenna wire thru marine block holding several window sash weights (approx
> weight 9# each.) easily hooked on stainless clevis to the weight you desire.
>
> Repeat at other tree.
>
> Two bike cables at $10, weights at zero to $5 (or use sand or water -- pints
> a pound the world around in a five gallon plastic jug.)
> Tree happy, XYL happy, no wear on halyard (protected by plastic - coated
> steel cable) and a few bucks for links (stainless recommended).
>
> Been up for fifteen years. Easy to change to experiment with OCF stuff, cage
> dipoles, etc.
>
> 73,
>
> Ed McCann
> AG6CX
>
>
>
> Sent from my iPhone
>
>> On Aug 11, 2016, at 8:34 PM, Wes Attaway (N5WA) <wesattaway@bellsouth.net>
>> wrote:
>>
>> I feel compelled to offer an alternative view.
>>
>> Jim Brown correctly pointed out that the question of pulleys and a
>> counterweight depends on how tall your trees are, how high your antennas are
>> in those trees, and how much the trees wiggle.
>>
>> In my case I have Pines that are over 100' tall. I put my OCF antennas at
>> the 60-70-ft level. The wiggling is minimal at that height, although the
>> trees do move. I leave a little slack in the antenna and I do not (and have
>> never) used counter weights. I use 3/16" or 3/8" black Dacron line over the
>> tree limbs.
>>
>> My method of attachment is that I get a line over an appropriate limb on the
>> center tree and I use it to haul up a pulley that has a black line in it. I
>> hoist the antenna center with that line. (There are two lines in the center
>> ....one to hold the pulley up and one to haul the antenna center up). I do
>> not use pulleys on the ends. I just shoot a line over a limb and pull a
>> black line up through and over to the end insulator (on each end).
>>
>> I know all the stories about abrasion and all the other stuff but not one
>> antenna has ever broken in the 15+ years that I have been at this QTH (and
>> we have had some hurricanes come through) except once when a big limb broke
>> off of a tree and crashed through the antenna wire.
>>
>> I am sure counterweights are appropriate for some situations but I don't
>> think you should just assume you need them.
>>
>> -------------------
>> Wes Attaway (N5WA)
>> (318) 393-3289 - Shreveport, LA
>> Computer/Cellphone Forensics
>> AttawayForensics.com
>> -------------------
>> -----Original Message-----
>> From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of Roger
>> (K8RI) on TT
>> Sent: Thursday, August 11, 2016 9:36 PM
>> To: towertalk@contesting.com
>> Subject: Re: [TowerTalk] Weight on ends of a OCF diploe
>>
>> In a typical installation for an OCF antenna, I'd think a concrete block
>> in a bucket should be more than adequate. Be careful not to exceed the
>> ratings of the antenna or tower. I agree with David on just using the
>> weight at the tree, but here (central Lower Michigan), I'd use a lot
>> more weight because of common spring ice storms
>>
>> In my case I have a similar arrangement, but it's a center fed, sloping,
>> half wave dipole with one end to the tower and the lower end to a
>> "substantial" tree. I use a relatively strong braided Dacron rope
>> (available from Davis RF and other sources). I depend on the elasticity
>> of the rope, but it's under "roughly" 200# of tension. To eliminate
>> center sag from the coax and choke weight. At this tension there is only
>> a slight visible sag, sighting along the length of the antenna from the
>> lower end. With SW antenna the rope runs through a half inch hose
>> around the back side of the tree. The hose is to protect the tree, The
>> NE antenna ties off to a forged lag bolt with an eye, in a very large
>> tree. At this size there is little danger of the mature tree growing
>> around the lag bolt. A younger tree might require moving the bolt every
>> few years.
>>
>> I use as much tension as desired within the strength capabilities of the
>> antenna and supports.
>> As a personal preference I'd use at least 100#, with the tower back
>> guyed ( if necessary) With my 45G, the antennas serve as tension
>> against each other. OTOH. My 100' tower's guying is strong enough that
>> back guying would not be needed even at 200# tension in just one direction.
>>
>> 73
>>
>> Roger (K8RI)
>>
>>> On 8/11/2016 Thursday 12:20 PM, David Robbins wrote:
>>> Enough weight to keep it reasonably tight. Normally only one end needs to
>>> be able to move, I would do that on the tree end instead of the tower.
>>> typical weights I have seen are buckets filled with concrete or rocks or
>>> sand, 20-30 pounds at most... if it is very long then maybe more weight.
>>>
>>> David Robbins K1TTT
>>> e-mail: mailto:k1ttt@arrl.net
>>> web: http://wiki.k1ttt.net
>>> AR-Cluster node: 145.69MHz or telnet://k1ttt.net:7373
>>>
>>>
>>>
>>> -----Original Message-----
>>> From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of
>> Chuck
>>> Gooden
>>> Sent: Thursday, August 11, 2016 16:14
>>> To: towertalk@contesting.com
>>> Subject: [TowerTalk] Weight on ends of a OCF diploe
>>>
>>>
>>>
>>> Retired recently and am getting back into ham radion.
>>>
>>> I am planning on putting up a 80 to 10 meter OCF antenna. The antenna
>> will
>>> be supported on a TV tower with the ends attached to some pine trees. I
>> am
>>> planning on using a pulley and some weight on the ends to allow for wind
>>> effects on the pine trees.
>>>
>>> My question is how much weight will I need at the ends to allow for wind
>>> movement of the trees?
>>>
>>> Thanks,
>>>
>>>
>>> _______________________________________________
>>>
>>>
>>>
>>> _______________________________________________
>>> TowerTalk mailing list
>>> TowerTalk@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>>
>>> _______________________________________________
>>>
>>>
>>>
>>> _______________________________________________
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>>
>>
>> --
>>
>> 73
>>
>> Roger (K8RI)
>>
>>
>> ---
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>>
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>>
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