Towertalk
[Top] [All Lists]

Re: [TowerTalk] Homebrew Crank-up

To: "Tower and HF antenna construction topics." <towertalk@contesting.com>
Subject: Re: [TowerTalk] Homebrew Crank-up
From: Stan Stockton <k5go@cox.net>
Reply-to: "Tower and HF antenna construction topics." <towertalk@contesting.com>
Date: Sat, 27 Mar 2010 17:15:12 -0500
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
As mentioned the lower section would be large (33 inch face) tower  
with 3 inch diameter legs.  The top would either be 55G or 65G.  I'm  
interested in ideas for rollers, etc.  Not worried about whether it  
will stay up or not.  There would be guy wires on lower section.

Stan, K5GO

Sent from Stan's IPhone

On Mar 27, 2010, at 4:45 PM, Kevin Normoyle <knormoyle@surfnetusa.com>  
wrote:

> If it's a crankup, I guess there's no guys.
>
> Rohn specs 70mph 0.8 sq ft wind area for 60' of unsupported rohn 55g
> Is that 15 lbs/sq ft?
>
> Even if you scale that back to 50mph, how can you get anything at the
> top of 75-5 = 70' of unsupported rohn 55g?
> If you guy it, why not leave it up?
>
> Rohn 55g is 18" o.c. 1.5" tubes? That's narrower than the base of all
> 72' crankups. (21.125" or so). tubes about the same.
> And there's more weight at the top (because no narrowing of sections).
>
> Isn't the real issue that you want a taper schedule to reduce stress
> lower down?
>
> seems like it just can't work?
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

<Prev in Thread] Current Thread [Next in Thread>