Element droop on the 402CD can be reduced considerably
by DOUBLE Walling the first piece of tubing in each element.
This will also raise the wind survival from >70 MPH to <90 MPH.
I also recommend putting a piece of dowel or tubing in the
ends and center of the boom to prevent compressing the boom
when tightening the U bolts.
My 402CD with the above modifications has survived estimated
90 MPH winds that took out dozens of 80 ft trees in my woods.
Tom N4KG
On Wed, 13 Nov 2002 "Jim W7RY" <w7ry@centurytel.net> writes:
> Thanks Jim!
>
> The TH7 and the 2 element 40 are both older antennas. I should be
> able to
> get at least 10' between em.
>
> I was thinking that it would be better to put the th7 on top. That
> way the
> element droop of the 40 would not be a factor. I know it would be
> better to
> have the 40 as high as possible...But with the element droop it
> could bring
> the spacing requirement to perhaps 8 feet....
>
> What do you think ?
>
>
> 73
> Jim
> W7RY
>
> ----- Original Message -----
> From: "Jim Harvey" <n0av@goldfieldaccess.net>
> To: "Jim W7RY" <w7ry@centurytel.net>
> Sent: Wednesday, November 13, 2002 9:01 PM
> Subject: Re: [Towertalk] 2eleL 40 and TH7 Stacking
>
>
> > Jim,
> >
> > I have a 402CD at 120' with three TH7DX's below it at 110/70/40'.
> This is
> on
> > a rotating Rohn 45 tower and all antennas are oriented in the same
> > direction. The SWR curves of all three TH7's are very similar.
> While I
> > normally use all three in a stack I have used the top antenna by
> itself
> and
> > the pattern seems to be about what I would expect for a single
> TH7.
> >
> > So although I have no specific tests to back this up the ten foot
> spacing
> > seems to work well for me. As I understand the NEW version of the
> CC 2EL
> 40
> > is not as forgiving when stacked with other HF antennas.
> >
> > This is not very scientific but I am pleased with my results. Good
> luck
> with
> > your project!
> >
> > 73, Jim N0AV
> >
> > ----- Original Message -----
> > From: "Jim W7RY" <w7ry@centurytel.net>
> > To: <towertalk@contesting.com>
> > Sent: Wednesday, November 13, 2002 10:43 PM
> > Subject: [Towertalk] 2eleL 40 and TH7 Stacking
> >
> >
> > > I know this has been discussed SEVERAL times before... BUT
> > >
> > > Has anyone had any REAL success stacking a 2 element Cushcraft
> 40 and a
> > > TH7DX on the same mast ?
> > >
> > > I do not want to have 1 rotated 90 degrees.
> > >
> > > How far apart did you need to put them ?
> > >
> > > Which antenna was on the top of the mast ? Why?
> > >
> > > Could you measure the interaction ? How?
> > >
> > > The tower will be 70' of Rohn 45 guyed with non metallic
> Phillistran.
> > >
> > >
> > > Thanks and It's been a while since I was here on Tower Talk.
> Time to put
> > up
> > > another tower after moving from Eastern Washington to Southwest
> > Washington.
> > >
> > > 73
> > > Jim W7RY
> > >
> > >
> > >
> > >
> > >
> > > _______________________________________________
> > > AN Wireless Self Supporting Towers at discounted prices,
> > > See http://www.mscomputer.com
> > >
> > > Wireless Weather Stations now $349.95. Call Toll Free,
> > > 888-333-9041 for additional information.
> > > _______________________________________________
> > > Towertalk mailing list
> > > Towertalk@contesting.com
> > > http://lists.contesting.com/mailman/listinfo/towertalk
> > >
> >
> >
> >
> >
>
>
> _______________________________________________
> AN Wireless Self Supporting Towers at discounted prices,
> See http://www.mscomputer.com
>
> Wireless Weather Stations now $349.95. Call Toll Free,
> 888-333-9041 for additional information.
> _______________________________________________
> Towertalk mailing list
> Towertalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
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