Hi Barry...
On this thread... Horizontal stacking of antennas is investigated thoroughly
in one of the issues of the ARRL Antenna Compendium.... (Don't have it handy,
so you will have to look it up) The title contained the word LARAE (or
similar) and referred to a 'Line aRray of Antennas in Echelon' As I
remember, for certain spacings, there is more than one beam heading where the
signals are in phase. He presents a number of 'solved' examples.. It is a
substantial article, with references...
I'm not sure that such an array is an advantage in a CONTEST situation,
where stations are worked at many different azimuth headings. Here, a broad,
main beam with a deep, forward footprint is desireable....
Denny
>From cgate!ocker@zool.interaccess.com (Charlie Ocker) Thu Jul 6 16:09:10 1995
From: cgate!ocker@zool.interaccess.com (Charlie Ocker) (Charlie Ocker)
Subject: Tower Mast Installation
Message-ID: <9507061509.AA12749@chasind.com>
Hola!
I'm putting up 70' of Rohn 45 for my contest station. I'd like to mount a
shorty forty 10 to 12 feet above my TH6 on a 15 foot mast, with 3 to 5 feet of
said mast below the top of the tower. A thrust bearing on top of the tower, and
another a couple of feet below the top will be used to keep the mast stable.
I've got a question for the cq-contest tower gurus:
How do you install a 15' mast safely without using a crane?
Many thanks and 73,
Charlie KD5PJ/9 ocker@chasind.com
>From kb1h@chowda.com (Dick Pechie) Thu Jul 6 07:56:33 1995
From: kb1h@chowda.com (Dick Pechie) (Dick Pechie)
Subject: 40/KT
Message-ID: <95070612000845825@chowda.com>
For what it's worth:
I had a Mosley S402 both above and below a KT34XA. The lower antenna
was at 76 feet and the higher 8 feet above. The only way it worked was
with the 40 meter beam above the tri-bander. Since then, I have
always put the 40 above any other antenna, including monobanders and
everything seems to work well. 73 Dick
>From Larry Tyree <tree@cmicro.com> Thu Jul 6 17:49:46 1995
From: Larry Tyree <tree@cmicro.com> (Larry Tyree)
Subject: WAE and PACKET
Message-ID: <199507061649.JAA22002@cascade.cmicro.com>
> Subj: WAEDC 1995 RULES
>
> DX packet cluster spotting is allowed in all classes.
An unfortunate rule in an otherwise neat event. No other major contest
has such a rule... then again, maybe this isn't a major contest.
Tree N6TR
tree@cmicro.com
>From oo7@astro.as.utexas.edu (Derek Wills) Thu Jul 6 18:40:02 1995
From: oo7@astro.as.utexas.edu (Derek Wills) (Derek Wills)
Subject: African contester
If anyone knows of any active YL CW contesters located in Africa,
please send me a list - if there is a significant response I'll
summarize it later, and explain why I need to know.
Derek AA5BT, G3NMX
oo7@astro.as.utexas.edu
>From k4sb@ix.netcom.com (Edward W. Sleight ) Thu Jul 6 19:19:22 1995
From: k4sb@ix.netcom.com (Edward W. Sleight ) (Edward W. Sleight )
Subject: High vs Low
Message-ID: <199507061819.LAA09287@ix3.ix.netcom.com>
I do not intend this unkindly, but, outside of a bullpen, I have never
seen as many mistated "half truths" ( I'm not going to dignify them by
calling them facts.) in the original message or any of the replies.
Has someone repealed the Law of Reciprosity?
1. True, you will, up to a point, lower the main take off lobe by
increasing heights. At some point, you will also, begin to intro-
duce so many high angle lobes that for all purposes, you have an
antenna which is excellent for receiving. And which very well show
an increased S meter reading. But at what angle are you receiving
the signal? Better said, at what "combination" of angles ? If you
want to be the top SWLer on the block, you're well on your way.
Again. remember, every lobe generated takes part of the total power
generated. If you put 1KW into 1 lobe, ( which doesn't exist for any
antenna ) you should get 1KW out. If you put 1 kw into an antenna which
has 10 lobes, it MUST devide between the lobes in direct ratio to the
sum of the lobes.
3. Do some simple trig and discover where the touchdown angle is for
a take off angle of 8 degrees. That's the problem with one of my 80
meter antennas. At 8000 miles or more, it's a killer...into Eu, it's
worthless.
4. The immediate field beneath ANY horz. polarized ant is an EXACT
duplicate of the field generated by the antenna. What is different
is the phase angle between the two upon recombination. And speaking of
that, that occurs, dependent on frequency, at a distance several
wavelenths from the antenna.
5. You don't "kill" SWR, and changing feedline length is of absolutely
no value. SWR seemingly has lost it's most important part, namely the
V which should be at the front. A VSWR of 10:1 is really insignificant
if proper matching is accomplished. VSWR is the voltage difference in
phase angle of the reflected wave vs the forward wave. If such can be
brought to a point where each is 180 degrees out of phase with each
other, they will cancel, and a VSWR will no longer exist. In reality,
you would not wish to accept that 10:1 unless your feedline length is
about 5 feet. But if your amp were mounted alongside the antenna, it
wouldn't make a hoot of difference. In practical cases however, you
must take into account the loss of power in db of the reflected wave
maing the trip back from the load to the source.
6. Put a pair of 5 element yagis spaced about 3/4 wave apart at about
60-70 feet, and if you really want to see the air turn blue, vertically
polarize them. ( mount them on a horz boom ) Such was proven about
45 years ago by Kraus, and Collins, and to an extent that Collins
stated that for all purposes, at all frequencies below 50 Mhz, vertical
stacking of yagis would produce superior results in all instances.
To sum it up, the old "higher the better" came from days long gone
when we simply didn't know any better for lack of proper
instrumentation.
OK, light your blowtorches....73, Ed K4SB
>From barry@w2up.wells.com (barry) Thu Jul 6 18:53:14 1995
From: barry@w2up.wells.com (barry) (barry)
Subject: WAE and PACKET
Message-ID: <FVwT8c5w165w@w2up.wells.com>
Larry Tyree <tree@cmicro.com> writes:
> > Subj: WAEDC 1995 RULES
> >
> > DX packet cluster spotting is allowed in all classes.
>
> An unfortunate rule in an otherwise neat event. No other major contest
> has such a rule... then again, maybe this isn't a major contest.
I see it as a contest rule ahead of its time, which will be better
understood when the others catch up.
>From jeffrey (j.) wittich" <jwittich@bnr.ca Thu Jul 6 19:40:00 1995
From: jeffrey (j.) wittich" <jwittich@bnr.ca (jeffrey (j.) wittich)
Subject: Phase noise question
Message-ID: <"12906 Thu Jul 6 14:45:56 1995"@bnr.ca>
Hi guys. A day or so after Field Day, I complained about station to
station interference, and asked for help. I got many responses full
of great information. Thank you. Thank you all. Band pass filters
and antenna arrangement should solve most of our problems.
There were several referances to broad-banded phase noise. Can
anyone tell me what this is? I suspect it has to do with the
output of the PLL mixing with strong signals nearby, but would
like some detail, if anyone can.
The FD chairman has called a lunch meeting for noon time on
Saturday for the band captains. I will by discussing your solutions
there, and expect to be asked to explain what this phase noise is.
Boy...work one sweepstakes and ya become the club expert on contesting.
Wish some of you were here!
73.
Jeff - AC4ZO
***********************************************************************
jwittich@b4pph107.bnr.ca *** CW ops let their fingers do the talking.
AC4ZO *** BNR claims they know nothing of my employment here.
***********************************************************************
>From lvn@fox.cen.com (Larry Novak) Thu Jul 6 20:49:21 1995
From: lvn@fox.cen.com (Larry Novak) (Larry Novak)
Subject: High vs Low
Message-ID: <9507061949.AA09722@cen.com>
Ed K4SB wrote:
>
> 3. Do some simple trig and discover where the touchdown angle is for
> a take off angle of 8 degrees. That's the problem with one of my 80
> meter antennas. At 8000 miles or more, it's a killer...into Eu, it's
> worthless.
>
Well, at 8 degrees takeoff and an F2 layer height of 240 miles (which is
about the highest it gets) my trig shows a one hop distance of 3415
miles. I don't know where you live, but for me that's Europe. To get a
one-hop distance of 8000 miles, the F2 layer would have to be about
562 miles -- there's nothin' out there! I know that refraction (vs.
reflection) has some effect here, but not that much.
^
/|\
/ | \
/ | \
/ | \
/ | \
-----------
|- d -|
d = H/tan(8 deg)
one-hop = 2*d
--
+=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-+
| Larry Novak \-\-\ email: lnovak@cen.com |
| Century Computing | Tel: (301) 953-3330 |
| 8101 Sandy Spring Road | Tel (@NRL): (202) 404-7682 |
| Laurel, MD 20707 | Fax: (301) 953-2368 |
| http://www.cen.com/ | Amateur Radio: K3TLX, C6AHE |
+=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-+
>From Swanson, Glenn, KB1GW" <gswanson@arrl.org Thu Jul 6 21:09:00 1995
From: Swanson, Glenn, KB1GW" <gswanson@arrl.org (Swanson, Glenn, KB1GW)
Subject: Phase noise question
Message-ID: <2FFC4329@arrl.org>
Greetings contesters,
In reference to the question below, you might want to check out the article
"Phase Noise and it's Effects on Amateur Communications" by KI6WX.
It was in QST, March 1988, p.14 (And, it's reprinted in
"The ARRL Radio Buyers Source Book Volume 2".)
73, --Glenn, KB1GW
----------
>From: jeffrey j. wittich
>To: cq-contest
>Subject: Phase noise question
>
>---------------------------------------------------------------------------
---
>Hi guys. <snip>
>
>There were several referances to broad-banded phase noise. Can
>anyone tell me what this is? I suspect it has to do with the
>output of the PLL mixing with strong signals nearby, but would
>like some detail, if anyone can.
>
>The FD chairman has called a lunch meeting for noon time on
>Saturday for the band captains. I will by discussing your solutions
>there, and expect to be asked to explain what this phase noise is.
>
>73.
>
>Jeff - AC4ZO
>
>
>
>From oo7@astro.as.utexas.edu (Derek Wills) Thu Jul 6 21:41:21 1995
From: oo7@astro.as.utexas.edu (Derek Wills) (Derek Wills)
Subject: High vs Low
Ed K4SB wrote:
>
> 3. Do some simple trig and discover where the touchdown angle is for
> a take off angle of 8 degrees. That's the problem with one of my 80
> meter antennas. At 8000 miles or more, it's a killer...into Eu, it's
> worthless.
>
Well, at 8 degrees takeoff and an F2 layer height of 240 miles
(which is about the highest it gets) my trig shows a one hop
distance of 3415 miles.
I suspect that you can't ignore the earth's curvature if you are talking
thousands of miles. I could probably have done this in my head a few
decades ago...
Depends what Ed meant by "simple trig" I suppose...
Derek AA5BT, G3NMX
oo7@astro.as.utexas.edu
>From oo7@astro.as.utexas.edu (Derek Wills) Thu Jul 6 22:59:12 1995
From: oo7@astro.as.utexas.edu (Derek Wills) (Derek Wills)
Subject: African contesterS
My earlier posting should have said "contesters", not contester,
maybe it was confusing...
I would simply like a list of active YL CW contesters in Africa.
Yes, I know it's hard to tell a YL from the CW, and no, it's not
for any immoral purpose.
Someone has already told me of I knew of, are there any others?
Derek AA5BT, G3NMX
oo7@astro.as.utexas.edu
|