If you're worried about wind, then take another look at the W0IBM
solution. The tubes were such that the weights and ropes were enclosed.
At max height, most of the rope was exposed, but the weights never were; at
min height, the rope and the extensions most of the rope (and the weights)
were in the tube, so any problem with wind carrying the weights never
happened. The W0IBM installation was effective in this manner for at least
three decades that I know about and maybe more.
Larry Wo0Z
On Sat, Oct 6, 2012 at 1:44 PM, SPWoo <jj_2_woo@yahoo.com> wrote:
> Hi Larry,
>
> Thanks for the reply. I get a lot of wind here and I'm afraid that the
> counterweight would swing in the wind and cause stress on the rope/wire. I
> wonder if there's a device that would retract the wire on a reel. Since I
> retract my tower after I'm done with each operating session I need an
> automatic device where I don't have to make a trip to the outside. I do
> have one of those coax arm supports already on the mast.
>
> My tower is also loaded to the max. so a rotatable dipole is out of the
> question. My other options are to mount the apex at the top of the bottom
> tower section, or to shunt feed the tower for 80m.
>
>
> Best Regards,
> Jonathan Woo
> (970) 646-1711
> ------------------------------
> *From:* Larry Loen <lwloen@gmail.com>
> *To:* SPWoo <jj_2_woo@yahoo.com>
> *Cc:* "towertalk@contesting.com" <towertalk@contesting.com>
> *Sent:* Saturday, October 6, 2012 1:58 PM
> *Subject:* Re: [TowerTalk] Inverted V on a retractable tower
>
> I have seen this very thing done.
>
> Basically, you need some sort of extender (if you're talking about US
> Tower, they sell such a device) so that the summit of the inverted V clears
> the tower sections.
>
> Then, you just need to have some sort of system at the ends of the antenna
> that amount to some fairly simple pulley system with weights to allow the
> wires to fall down when the tower is cranked over for service.
>
> On a tower at W0IBM, I saw something like a commercial product that did
> this. It was tubes of maybe 2 inches in diameter attached to courtyard
> walls (the tower was in a courtyard). When the tower came down, the
> weight-and-rope at the end of the wire antenna retracted into the tubes
> well enough. We could detach or keep the thing intact from the top of the
> "V" when we tilted it over. I believe we typically detached it for
> service; the system was designed such that the wire was simply "where it
> needed to be" when the tower was retracted (but not cranked over) so we
> could reattach it after we cranked the tower back from horizontal to
> vertical.
>
> At my forever under development new shack, I plan to do something similar
> with my US Tower retractable. I have an old trick of putting conduit over
> rebar as a distant antenna support for simple wire antennas. I'll probably
> resort to the same weight-and-pulley trick -- I may even settle for a
> simple "eye hook" instead of bothering with a pulley.
>
> The nice thing about the rebar-covered-by-conduit is that while it is
> plenty stable, it is easy enough to simply lift the conduit off of the end
> of the rebar (the fit is tight, but not overly so). So, everything is
> serviceable. With my simpler scheme, the wire may end up on the ground,
> but most of it would be away from the tower and, I presume, easy to manage
> without kinking and coiling.
>
> If I discover I can manage 20 feet of conduit with my scheme, then it is
> more like the W0IBM installation, because it would be at about the same
> height as the retracted tower.
>
>
> Larry Wo0Z
>
> On Sat, Oct 6, 2012 at 11:29 AM, SPWoo <jj_2_woo@yahoo.com> wrote:
>
> Hi All,
>
> Does anyone know how to install an inverted V antenna for 80m on a
> retractable tower? Is there anything that could be done to prevent the
> wires from laying on the ground when the tower is retracted? Thank you and
> 73.
>
> Best Regards,
> Jonathan Woo
> (970) 646-1711
> _______________________________________________
>
>
>
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> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
>
>
>
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