[RTTY] Novel idea?

[Joe Subich, W4TV]

RotorEZ from Idiom Press will calculate the offset automatically 
by closing a switch.  It might be possible to read the direction 
for both antennas from the bottom rotor and control both the 
top rotor and the offset with a simple toggle switch (0/90). 

73, 

    ... Joe Subich, W4TV 
        microHAM America, LLC. 
        www.microHAM-USA.com 

PS. Don, the second resonance on the D-40 is closer to 17 meters 
    than 15 (AO says 75 + j50 at 18.1 vs. 200 + J250 at 21.1).

 

> -----Original Message-----
> From: rtty-bounces at contesting.com 
> [mailto:rtty-bounces at contesting.com] On Behalf Of Dave W7DPW
> Sent: Thursday, November 24, 2005 2:50 AM
> To: Doug Faunt N6TQS +1-510-655-8604; t3 at semarg.ath.cx
> Cc: rtty at contesting.com
> Subject: Re: [RTTY] Novel idea?
> 
> 
> RT-20 rotor will do just that. (Spendy)
> 
> http://www.greenheronengineering.com/
> 
> It was hiugh lited in current NCJ
> 
> Dave W7DPW
> 
> ----- Original Message ----- 
> From: "Doug Faunt N6TQS +1-510-655-8604" <faunt at panix.com>
> To: <t3 at semarg.ath.cx>
> Cc: <rtty at contesting.com>
> Sent: Wednesday, November 23, 2005 11:43 PM
> Subject: Re: [RTTY] Novel idea?
> 
> 
> >    Date: Wed, 23 Nov 2005 20:09:33 -0500
> >    From: t3 <t3 at semarg.ath.cx>
> >
> >    I can't see a problem..
> >    except, maby the rotor cable on the upper rotor may get 
> large doses
> of
> >    RF while it passes between the A3S
> >    a simple fix could be sheilded cable..
> >
> >    Tony
> >    NN1D
> >
> > Another fix for this would be to run the control cable fro 
> the rotator
> > up through the mast, come out the top and then down to the rotator.
> >
> > I like the idea, and it cries out for a couple of computer 
> controlled
> > rotators and a microprocessor to be the glue to actually 
> calculate and
> > display the radiating directions for the top antenna.  I'm not
> > volunteering, though.
> >
> > 73, doug
> >
> >
> >    Don Hill AA5AU wrote:
> >    > This is not directly related to RTTY, but again, I trust the
> opinions of those
> >    > on this reflector.  A great bunch of ops here.
> >    >
> >    > I've not ever heard of anyone doing this before.  But 
> it seems to
> be an
> >    > excellent solution for me.  I was going to keep this 
> secret, but
> I just can't.
> >    > I need some input from others.
> >    >
> >    > I'm in the middle of rebuilding my main tower.  Right now, it's
> at 46 feet
> >    > waiting for me to install the first set of guys.  Why 
> the unusual
> height?  Six
> >    > feet of tower sticks out from the concrete base.  What I have
> left is one more
> >    > 10' midsection, then the 9' top section.  The tower will be at
> 65' when
> >    > finished.
> >    >
> >    > Anyway, for those following my rebuild may remember 
> that I wanted
> to install a
> >    > 40 meter beam.  Well, I cheaped out on this idea.  In order to
> get something up
> >    > for Roundup, I've purchased a new A3S and D40 (D40 is 
> a Cushcraft
> 40M dipole).
> >    > You have to realize that my ground crew consists of my wife and
> the neighbor's
> >    > German Shepard.  So I have to stay lightweight right now.
> >    >
> >    > Prior to Katrina, my main antenna was an A3S with the 40 meter
> add-on.  With the
> >    > D40, the rotatable dipole will now be separate from 
> the tribander
> and I can use
> >    > both antennas at the same time with my SO2R setup.
> >    >
> >    > Here's the kicker.  I will install the D40 above the 
> A3S and want
> at least 10'
> >    > of separation.  In trying determine if I should align the D40
> with the A3S or
> >    > offset it 90 degrees in azimuth, I have come up with a radical
> idea of
> >    > installing a separate rotor above the A3S.  My main 
> rotor is the
> M2 RC2800.  It
> >    > will sit inside the top section.  I will then install 
> a piece of
> 2" aluminum
> >    > conduit (mast) from the rotator up through my thrust 
> bearing, but
> only sticking
> >    > out of the tower a couple of feet.  I will install the 
> A3S here.
> On top of the
> >    > conduit mast sticking a couple feet from the top of the tower,
> I'll install what
> >    > will probably be a Yaesu G-450A with the mast mount (haven't
> purchased yet) and
> >    > then a 10' piece of 2" aluminum conduit.  Near the top 
> of the 10'
> piece of
> >    > conduit, I'll install the 18 lb D40.  I've compiled the figures
> and the M2 is
> >    > more than enough to rotate everything and the G-450A 
> will handle
> the D40 with no
> >    > problem.  What I like about the G-450A is that it can be set to
> stop at any
> >    > direction and shows an LED for overlap which I can set at 90
> degrees.  Also,
> >    > unlike the G-800S, you must push the left or right 
> button to move
> it, so it
> >    > won't rotate all the way around by itself.  This is important
> because of the
> >    > slack I'll need in the RF and rotor control cables from the D40
> and G-450A.  The
> >    > overlap LED will alert me that the D40 is offset.  Keep in mind
> that the D40
> >    > will only need to be rotated up to 90 degrees offset from the
> A3S, never any
> >    > more than that.
> >    >
> >    > I've been thinking about this for weeks.  I can't think for any
> reason why it
> >    > wouldn't work.  I hope to simulate the entire setup on the
> ground, possibly this
> >    > weekend using an old CDE mast mounted rotator I have.  
> Other than
> the G-450A, I
> >    > have all the other hardware already.  Has anyone ever heard of
> this setup
> >    > before, a rotor on top of a rotor?
> >    >
> >    > By the way, updates on the towers on my new antenna page at
> >    > http://www.aa5au.com/antennas/antennas.html
> >    >
> >    > 73, Don AA5AU
> >    >