Hi Tim,
> Just climbed the tower, loosened the boom u-bolts, rotated the boom and
retightened.
That can't be done! The TH7 has bolts through the boom for alignment at the
boom to mask fitting, only the elements can be changed to realign to
horizontal. I have photos of mine when it was on the ground:
http://cid-f3b31b3a46a60552.skydrive.live.com/browse.aspx/Public?uc=2
See photos 3789 and 3790 if you wish (they are big).
Eric - VE3GSI
> -----Original Message-----
> From: N3XX
> Sent: March-23-09 6:29 PM
> To: Bob Alexander; TowerTalk@contesting.com
> Subject: Re: [TowerTalk] correcting a stupid mistake
>
> Had the same thing here, but not that far off from horizontal. Just
> climbed
> the tower, loosened the boom u-bolts, rotated the boom and retightened.
>
> 73,
> Tim - N3XX
>
> ----- Original Message -----
> From: "Bob Alexander" <realex@flash.net>
> To: <TowerTalk@contesting.com>
> Sent: Monday, March 23, 2009 2:21 PM
> Subject: [TowerTalk] correcting a stupid mistake
>
>
> Howdy,
>
> I find myself in the embarrassing position of having to correct a
> stupid
> mistake that was made when my TH7 was reassembled after repairs from
> storm damage.
>
> As we were bolting the TH7 to the mast (after raising it over the
> house,
> around one tree and over another) we realized the mounting plate on the
> boom was not normal to the elements. It was about 5 ½ degrees off
> vertical when we leveled out the elements and tightened all the
> hardware. So, I have a tribander that works perfectly but has
> element
> ends on one side 18 inches above the boom and 18 inches below the boom
> on the other side. After the ordeal of getting it to the top of the
> tower we elected to leave it as is on the tower.
>
> Without taking the antenna down, the only way I can see to level out
> the
> elements is to put a shim between the mast bracket and boom plate. A
> tapered shim about ¼ inches thick should do the trick.
>
> My question is, from a mechanical standpoint, is this a good idea?
>
> It works well so why fix it? When the storm damage occurred, there was
> a two element 40 stacked with the tribander. I decided to simplify
> things and only go back up with the tribander. The 40 was replaced
> with
> a pair of phased 40 mtr verticals. Now, the XYL has decided the
> verticals clash too much with her landscaping. Green paint is not an
> option
>
> Any opinions on the shim or references to mechanical texts on the
> subject will be appreciated.
>
> I really do not want to come down and back up with the TH7 if I can
> avoid it.
>
> 73,
>
> Bob, W5AH
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