With QSB and everything, it is not always easy to peak a beam for the
strongest signal. Sometimes you can arrive at the correct result by nulling
out the signal and then turning the antenna 90 degrees. When I lived in
Cedar Rapids, Iowa, I had a two-element quad, and that was a good strategy.
Another strategy is to know how many seconds it takes for your rotor to turn
your antenna through a given angle. The Tailtwister rotor takes 48 or 50
seconds to make a full revolution. My beam has dual driven elements plus
one reflector and two directors active on 20 and 15 meters. An additional
director is active only on ten. With this antenna at 60 feet elevation, on
the 20-meter net, I find it makes a big difference if I am 30 or 45 degrees
off.
Lloyd Rasmussen, Kensington, Maryland
Home: http://lras.home.sprynet.com
Work: http://www.loc.gov/nls
> -----Original Message-----
> From: colin McDonald [mailto:[log in to unmask]]
> Sent: Tuesday, February 28, 2012 4:18 PM
> To: [log in to unmask]
> Subject: Re: Accessible Roatators
>
> the beam must be tight enough to be able to do that by signal strength
> alone?
> I've noticed when playing around with the 3 element tri bander at the club
> station that it's almost impossible to aim the beam at a station and
> direct
> it precisely with signal alone...there seems to be a rather wide window
> with
> that particular beam.
> For instance, south america seems to be just as strong across about 80
> degrees between southwest, and southeast.
> I suspect it's because a 3 element beam has a pretty wide lobe on the
> front.
>
> 73
> Colin, V A6BS
> ----- Original Message -----
> From: "Lloyd Rasmussen" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Tuesday, February 28, 2012 5:10 AM
> Subject: FW: Accessible Roatators
>
>
> > Yes, I could do those things. And sometimes I get a little carried away
> > in
> > aiming the antenna precisely at a station. So I haven't bothered.
> >
> > Lloyd Rasmussen, Kensington, Maryland
> > Home: http://lras.home.sprynet.com
> > Work: http://www.loc.gov/nls
> >
> > -----Original Message-----
> > From: colin McDonald [mailto:[log in to unmask]]
> > Sent: Tuesday, February 28, 2012 12:59 AM
> > To: [log in to unmask]
> > Subject: Re: Accessible Roatators
> >
> > hmmm, shouldn't be hard to find a small chicken head knob and put sticky
> > dots, or a dab of glue that will harden into a dot at the east and west
> > points on the pannel behind the knob?
> > I'm sure you thought of that, but it might make it easier to get to
> those
> > directions more quickly and with some greater certainty.
> > 73
> > Colin, V A6BS
> >
> > ----- Original Message -----
> > From: "Lloyd Rasmussen" <[log in to unmask]>
> > To: <[log in to unmask]>
> > Sent: Monday, February 27, 2012 7:41 PM
> > Subject: Re: Accessible Roatators
> >
> >
> >> The stock knob is about a quarter inch in diameter, and there isn't a
> lot
> >> of
> >> room for a larger knob. We filed a notch in the knob. Since the
> >> potentiometer doesn't cover the full 360 degrees, but only about 300,
> >> north
> >> is straight up, both south directions are at the extremes of the range,
> >> but
> >> east and west are a little above horizontal. So you can only
> >> approximately
> >> set directions.
> >>
> >> Lloyd Rasmussen, Kensington, Maryland
> >> Home: http://lras.home.sprynet.com
> >> Work: http://www.loc.gov/nls
> >>
> >>
> >>> -----Original Message-----
> >>> From: Ed Malmgren [mailto:[log in to unmask]]
> >>> Sent: Monday, February 27, 2012 7:43 PM
> >>> To: [log in to unmask]
> >>> Subject: Re: Accessible Roatators
> >>>
> >>> Howdy Lloyd How accrate is the pointer on the cal. knob? For
> >>> example
> >>> is straight up north and south at
> >>> the ends. tnx and 73Ed K7UC
> >>>
> >>> --------------------------------------------------
> >>> From: "Lloyd Rasmussen" <[log in to unmask]>
> >>> Sent: Monday, February 27, 2012 5:31 PM
> >>> To: <[log in to unmask]>
> >>> Subject: Re: Accessible Roatators
> >>>
> >>> > I turn my KT34XA with a Tailtwister rotor. The control box is the
> >>> > type
> >>> > made
> >>> > by Hy-Gain for probably the last 50 years. It has a paddle switch
> for
> >>> its
> >>> > AC power, three spring-loaded switches mounted side-by-side for
> >>> > directional
> >>> > control and brake control, and a small potentiometer for calibrating
> >>> > the
> >>> > directional indicator. I had W3MC install an Idiom Press control
> >>> > board
> >>> > inside it. This adds brake delay, and the knob's function is
> changed
> >>> > so
> >>> > that you can turn it toward the direction you want, then tap the
> >>> > center
> >>> > button and the rotor will go to that direction. For more precise
> >>> control,
> >>> > this board also has a serial interface. I have this hooked to my PC
> >>> > through
> >>> > a USB-to-serial adapter, and it is controlled and read by N1MM. I
> >>> > never
> >>> > got
> >>> > the Ham Radio Deluxe rotor interface to work properly with
> >>> > Window-Eyes,
> >>> so
> >>> > when I am running the net and telling you that I am pointing to 240
> >>> > degrees,
> >>> > etc., N1MM is running. I don't use N1MM to log the net, however,
> >>> finding
> >>> > that Notepad works fine for that.
> >>> > 73,
> >>> > Lloyd Rasmussen, W3IUU, Wheaton, Maryland
> >>> > Home: http://lras.home.sprynet.com
> >>> > Work: http://www.loc.gov/nls
> >> ...
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