[TowerTalk] Re: Beam Headings
K7GCO@aol.com
K7GCO@aol.com
Tue, 14 Mar 2000 15:16:25 EST
In regard to the beam heading problem, there were many suggestions. The most
important application is those with very narrow beam widths like on VHF that
was pointed out but peaking is still the practice. The Twin 11 element 2M
beams needed to be right on. AA4LR's is a very good summary and suggestion.
N5WA's was also great. There has been some "Mole Hilling" here. This one was
a classic. "Just watch the birds. They fly north in the spring and south in
the fall. BRS" This has a serious deficiency. You can calibrate only twice
a year.
There are beams sold the "Mole Hillers" buy that you hardly need a rotator
for. The TA-33 and all band quads with the DE's tied together. You will get
as many calls to CQ's in the frontal 90 degrees as you do from the back 270
degrees. Example: I call CQ DX on Europe and a rare China stations comes
back off the side. I call CQ DX on JA and a LU comes back. I call a CQ east
and a ZL comes back off the side and back over a hill. The designer told me
"I got them long path". Yeah right! The RF that took a right angle turn on
its long path way to China he couldn't explain away? I suggested that the
path over the magnetic pole put some "Left Circular SSB RF English" on the
signal and he agreed. I hear a DX pile up and not knowing where the stations
is, I tried to peak it and over about 150 degrees I couldn't peak it. With a
2 element quad I had on 6M I could peak a station with one pass (on the same
transmission) even with a 1 RPM rotator. I use a speeded up rotator on it
now--a Prop Pitch. Over kill but it's very very functional at 5 RPM on small
beams for this and just checking other directions quickly and F/B checks
while the other station is still talking. Further with 1 RPM, it's too damn
slow to peak other than a steady carrier and for F/B checks.
When you have a beam with a good E plane pattern and a speeded up rotator,
it's "Psychologically a real joy, highly functional and impressive as hell".
I run lots of patterns. When I demonstrate this to others, some really turn
on and see how useful it is. Others just can't see for some reason the
merits of it. I have a 7 element 10M beam and would you believe, I used to
ask them what part of town they live in?
I was cured of the slow 3/4 RPM PP speed in 1948. I turned on the rotator
and went into another room, got distracted, went to another room due to an
immediate problem. Later I came into the shack and someone had stolen the
receiver off the table even with the window out the open ground level window
but I could still hear it. It had to be close. The 110V cord was still
plugged in and running out the window. The Prop Pitch 9000/1 gear ratio
wrapped the RG8 around the 1.5" mast and was a very very powerful winch. It
cleanly and silently pulled the receiver out the window and was on it's way
to the roof, a big disconnect and crash had I not walked in when I did. To
top it off a station was calling me on schedule on it's journey up to the
roof. That's what I heard in the other room just in time. I reversed the
Prop Pitch and pulled the receiver back into the shack--without a scratch
while the schedule station was calling me. He wouldn't believe my story
until he inspected my shack and window.
Looking up at a receiver repeating your call being Prop Pitch Winched up an
outside wall is a sight you just don't see very often.
I added a momentary switch for rotation after that and speeded up the
rotator. I just found another momentary switch at a flea market. I have a
way to mechanically speed up all rotators fairly easy which is easy to
explain
K7GCO.
In a message dated 14.03.00 09:14:32 Pacific Standard Time, aa4lr@radio.org
writes:
<< On 3/13/00 11:37 PM, Wes Attaway at wes@attawayinterests.com wrote:
>Call me a simpleton if you want to, but I think the recent thread on "lat,
>long, beam headings, etc" begs the question: Why worry about exact headings?
Good question.
>I offer the following thoughts:
>
>1. Most HF beams have 3-db beamwidths of somewhere between 30 and 60
>degrees
So, it doesn't matter where you're pointed, exactly.
>2. There is usually some degree of "play" as the beam rocks back and forth
>in the wind;
>3. Most rotor direction indicating schemes are not perfectly accurate all
>the way around, and tend to become less accurate over time;
And you can't tell where you're pointed, exactly.
>4. Many DX paths for "best signal" (particularly on long path routes) turn
>out to be dramatically different from what you would expect from looking at
>a chart; you find the best signal, if necessary, by moving your beam back
>and forth;
This seems to contradict point 1 -- if the beamwidths are really that
broad, do you really need to rock the antenna back and forth to peak it
up? Psychological value, perhaps?
>5. Finally, after about 45-years of DXing with all sorts of beams (the last
>20 with two big Telrex yagis) I have yet to find a single situation where
>knowing the precise heading of the DX, and the precise direction my beam was
>pointing, had any bearing on my ability to work the DX. I use essentially 4
>directions ..... approximately SE, NE, NW, and SW. Sometimes I use E, N,
>and W (I don't remember ever pointing my beam due South). That's it.
This is a great point. Precise aiming isn't needed -- fire the beam
"thataway" will do it. >>
Except with 12 or more dBi gain. K7gco
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