Hi Brian
Yes it does appear to be of good value. We all take the forces for granted but
to work safely need to stop and think.
This is why the club called a halt to work and got out the slide rule.
We are hoping to document our findings in the interest of assisting others.
That's why this is a great hobby as there is so much shared experience out
there.
Thanks for your input.
73
Robert
Robert Rawson
M0RCX
North Wakefield Radio Club
www.g4nok.org
On 28 Apr 2013, at 16:25, Brian Alsop <alsopb@nc.rr.com> wrote:
> Robert,
>
> Sent this to the wrong person. Perhaps the variable counterweight idea is of
> some value. It transfers a good part of the cable load to the tower. The
> question is: can the tower take the load? I would think so.
>
> 73 de Brian/k3ko
>
>
> -------- Original Message --------
> Subject: RE: tilt tower
> Date: Sun, 28 Apr 2013 11:20:44 -0400
> From: David Aslin <david@aslinvc.com>
> To: Brian Alsop <alsopb@nc.rr.com>
>
>
>
> RE: tilt tower
>
> Thanks Brian.
>
> My guess is you intended this for the original poster,Robert M0RCX(m6bfd
> at yahoo.com)
>
> Nonetheless, I found the concept very interesting as I have been
> considering options for counter-weightingfollowingG4HUP's work on
> luffing cable forces - which are way higher than most people realize!
>
> 73
>
> Dave G3WGN
>
> -----Original Message-----
> From: Brian Alsop [mailto:alsopb@nc.rr.com]
> Sent: Sunday, April 28, 2013 1:11 PM
> To: David Aslin
> Subject: tilt tower
>
> Hi David,
>
> I had an EZ-WAY tilt over towers several times over the years.
>
> It consists of a tilt post 6 to 8' up and winch with the winch cable
> attached to the bottom of the tower.
>
> I found life got easier if I had a "variable counterweight" attached to
> the tower bottom. It consisted of a string of 4 cement blocks attached
> together with rope. They are layed out on the ground in a string. As
> the tower is tilted over, the first block is lifted off the ground, then
> the next, then the next. When all 4 blocks off the ground, it becomes a
>
> 250 pound counterweight. This made raising and lowering less work and
> the cable experienced less tension. The reverse happens on tilting up.
>
> BTW. The interaction effect you perceive may be quantified by having
>
> somebody do EZNEC modeling. In fact, rotation of one or more of the
>
> yagi's 90 degrees can essentially eliminate the interaction. I've had
> to do this with stacked WARC/non-WARC antennas on the same mast.
>
> 73 de Brian/K3KO
>
>
> -----
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