> -----Original Message-----
> From: Peter Sundberg [SMTP:sm2cew@telia.com]
> Sent: Thursday, January 02, 2003 1:21 PM
> To: Steve Katz
> Subject: RE: [Towertalk] AR-22 Rotor Control Box Question
>
> Very true Steve. I don't think the AR22 is the best rotor choice, but it
> is
> far better than some of the other tv antenna rotors. When I used the AR22
> for my moobounce array (6x16 el on 144MHz) I did indeed use a thrust
> bearing and used selsyns as indicators. I operated the rotor from a
> homebuilt control unit with push buttons to activate it instead of the
> clickety click unit..
>
[Steve Katz] Peter, you are indeed lucky! When I used an AR-22
with just a single 2m long-boom Yagi back in the mid-1960's (at that time,
it was a single 15L Telrex, 28' boom), the first windstorm stripped the
gears, and that was that.
> It is still 100% but in the garage for the moment. I now use a homemade
> worm drive rotor for the 2 mtr EME array that has grown considerably, and
> the worm gear rotor holds it in the same position in winds which of course
> the AR22 did not do.
>
[Steve Katz] Worm gear rotors are definitely very nice, and don't
even need a brake. If I ever get active in EME again (as I once was, in the
1980's), I'll go that route, Peter. 73 es DX! -Steve, WB2WIK/6
> 73/Peter SM2CEW
> www.qsl.net/sm2cew
>
>
>
> At 20:54 2003-01-02 , you wrote:
> >
> >
> >
> >> I would not call the AR22 indication system a servo control system. It
> is
> >> a
> >> solenoid stepper system that is actuated by a switch in the rotor unit.
> >> Very simple. The good thing is that the readout is recalibrated in
> about
> >> 60
> >> seconds, the time it takes to rotate back to one of the end stops.
> >>
> > [Steve Katz] Yes, that's true. But with a 3L 20m beam, you
> >probably don't need to adjust it in 6-12 degree increments at all, since
> the
> >beamwidth is probably 50-60 degrees. When using UHF satellite antennas,
> >real 6-12 degree incremental adjustments can actually be necessary, so
> the
> >"recalibration" process, which indeed takes 60 seconds, might need to be
> >performed several times per hour. -WB2WIK/6
> >
> >
> >> As for the torque, I find it pretty good for what it is. I have had a 3
> el
> >> monobander for 20m on one for years without a problem, no thrust
> bearing.
> >>
> >> The annoying thing is the loud CLICK the control unit makes, it can
> wake a
> >> whole household up in the middle of the night.
> >>
> >> It would be pretty easy to build a new silent control unit that catches
> >> the
> >> pulse and displays the direction in degrees, counting + or - 6 degrees
> on
> >> every pulse from the rotor.. but that is another story. Isn't that what
> >> the
> >> M2 rotor control unit is doing, pulse counting ?
> >>
> > [Steve Katz] Surely. I think simply trading up to a CD-45 or
> >equivalent, which can be turned even 3 degrees at a time without
> upsetting
> >calibration (and has a quiet controller!) is a far better choice. As for
> >torque, you may be lucky or have a well-balanced load, but I've never
> seen
> >the AR-22 that I could not stop with my hands. I can't stop a HAM-M
> series,
> >at least not without a very large lever.... -WB2WIK/6
> >
> >
> >> 73/Peter SM2CEW
> >>
> >>
> >>
> >>
> >>
> >>
> >> At 15:42 2003-01-02 , you wrote:
> >> >Jon,
> >> >
> >> >It does sound as though the rotor is binding in one direction. Make
> sure
> >> >the load above the rotor is very balanced; any amount of imbalance
> when
> >> an
> >> >AR-22 is used without a thrust bearing will make it practically stop
> --
> >> it
> >> >doesn't have nearly the torque of a CD-45 or HAM-M type.
> >> >
> >> >Also, the AR-22 servo control system does not work well if the rotor
> is
> >> used
> >> >for small incremental changes in direction. Remember, these were
> >> >inexpensive rotors (I bought several brand new in 1966-67 for
> $39/each,
> >> >complete with the control box) intended to turn TV antennas that were
> not
> >> >highly directional; it was normal to crank the rotor 45 degrees or
> more
> >> at a
> >> >time, to favor TV signals from another city. It would have been
> >> extremely
> >> >rare for anyone to need to turn their TV antenna only two or three
> >> "clicks"
> >> >(12-18 degrees) at a time, as from practically nowhere are cities this
> >> close
> >> >together.
> >> >
> >> >If you need to turn the rotor only 12 degrees (two "clicks" worth of
> >> >rotation), it is best to crank it ten clicks forward, then eight
> clicks
> >> >back. That accomplishes the 12 degrees of desired rotation without
> >> >stressing the sytem beyond what it can handle.
> >> >
> >> >It was very common, even with brand new AR-22's, that if you used the
> >> rotor
> >> >to make 1-2-3 "click" adjustments, after doing so the indicator would
> be
> >> >quite far off. That was normal, and I don't recall any known fix for
> >> this
> >> >-- it's inherant in the design.
> >> >
> >> >The AR-22 is not the greatest choice for highly directional antennas,
> no
> >> >matter how lightweight they may be.
> >> >
> >> >WB2WIK/6
> >> >
> >> >"If everything seems under control, you're just not going fast
> enough." -
> >> >Mario Andretti
> >> >
> >> >> -----Original Message-----
> >> >> From: Jon Ogden [SMTP:na9d@speakeasy.net]
> >> >> Sent: Wednesday, January 01, 2003 4:17 PM
> >> >> To: Randy Wing; towertalk@contesting.com
> >> >> Subject: Re: [Towertalk] AR-22 Rotor Control Box Question
> >> >>
> >> >> on 1/1/03 4:30 PM, Randy Wing at rwing@southwind.net wrote:
> >> >>
> >> >> > Jon,
> >> >> >
> >> >> > I oversimplified. What I meant to add to this was that there is
> an
> >> >> > adjustment on the CDE for correcting for incorrect amounts of
> slew.
> >> >> >
> >> >>
> >> >> No, I've not done that. I have no instruction manual. How do you
> do
> >> >> that?
> >> >>
> >> >> Also, the rotor seems to turn faster in one direction (clockwise)
> than
> >> in
> >> >> the other (CCW). The "clicks" come a lot slower. Is it possible
> that
> >> I
> >> >> am
> >> >> binding a little bit in one direction?
> >> >>
> >> >> Thanks,
> >> >>
> >> >> Jon
> >> >>
> >> >> -------------------------------------
> >> >> Jon Ogden
> >> >> NA9D (ex: KE9NA)
> >> >>
> >> >> Citizen of the People's Democratic Republik of Illinois
> >> >>
> >> >> Life Member: ARRL, NRA
> >> >> Member: AMSAT, DXCC
> >> >>
> >> >> http://www.qsl.net/na9d
> >> >>
> >> >> "A life lived in fear is a life half lived."
> >> >>
> >> >>
> >> >> _______________________________________________
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> >> >
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