Tnx all fer KD7P info
py2ny at SP-gw.ampr.org
py2ny at SP-gw.ampr.org
Thu Nov 16 19:45:18 EST 1995
Thanks for all friends that sent KD7P E-mail address.
A new way to get this kind of info learned: lookup at qrz.com
I'm happy to have teachers like all of you, specially:
NG3K, WB4IUX, KS4XG, WA8LLY, W1NG, KB2HUN
that sent one message for me !! Thanks and Good DX for all
PY2NY - Vitor
>From bwruble at ix.netcom.com (Brian Wruble) Fri Nov 17 12:43:31 1995
From: bwruble at ix.netcom.com (Brian Wruble) (Brian Wruble)
Date: Fri, 17 Nov 1995 04:43:31 -0800
Subject: ETO to be Acquired
Message-ID: <199511171243.EAA07001 at ix4.ix.netcom.com>
Today's Wall Street Journal carries the story that Ehrhorn
Technological Operations Inc. (ETO) has signed a letter of intent to be
acquired by Aplied Science & Technology Inc. of Woburn MA for $17.5 million
(70% in cash and the rest in stock). Applied Systems makes systems for
making industrial diamonds and semiconductor material.
From: Brian F. Wruble, W1HIC
bwruble at ix.netcom.com
>From KAY, LEONARD" <LKAY at pria.com Fri Nov 17 16:33:00 1995
From: KAY, LEONARD" <LKAY at pria.com (KAY, LEONARD)
Date: Fri, 17 Nov 95 08:33:00 PST
Subject: ETO to be Acquired
Message-ID: <30ACB9B2 at msgate.pria.com>
This makes perfect sense..... for those of you unfamiliar with the
field, Applied Systems makes 'ion implanters' and as such has an
ENORMOUS demand for really-big-QRO RF amplifiers. In fact, I
think they're Dick's biggest non-ham business (or should I say, we're
his biggest non-industrial business?!?)
Hey, does that mean direct Alpha pick-up for 1-land now? :-)
--------------------------------------------------------------------------
Leonard Kay, KB2R | "But we are not dealing with the
PRI Automation, Inc. | normal world. We are chasing DX."
Billerica, MA 01821 | -- W9KNI, 'The Complete DXer'
lkay at pria.com or KB2R>K1EA |
Editor, YCCC Scuttlebutt | #include <disclaimer.h>
--------------------------------------------------------------------------
----------
>From: owner-cq-contest
>To: cq-contest
>Subject: ETO to be Acquired
>Date: Friday, November 17, 1995 4:43AM
> Today's Wall Street Journal carries the story that Ehrhorn
>Technological Operations Inc. (ETO) has signed a letter of intent to be
>acquired by Aplied Science & Technology Inc. of Woburn MA for $17.5 million
>70% in cash and the rest in stock). Applied Systems makes systems for
>making industrial diamonds and semiconductor material.
>From: Brian F. Wruble, W1HIC
bwruble at ix.netcom.com
>From Douglas S. Zwiebel" <0006489207 at mcimail.com Fri Nov 17 14:55:00 1995
From: Douglas S. Zwiebel" <0006489207 at mcimail.com (Douglas S. Zwiebel)
Date: Fri, 17 Nov 95 09:55 EST
Subject: WHERE'S THE BEEF?
Message-ID: <10951117145501/0006489207PK1EM at MCIMAIL.COM>
I'm sitting here looking over my October 1995 CQ magazine on page 118;
you know, the ACTIVE ZONES box. I find it really amazing at what it
(doesn't) take to make some of these boxes and, more specifically,
how little competition there is in zones 3 & 25. Take a look at these
comparisons:
ZONE top score 5th score % of #1 10th score % of #1
5 4.037 M 3.177 M 78.7% 2.317 M 57.4%
4 2.021 M 1.496 M 74.0% 0.607 M 30.0%
3 1.611 M 0.859 M 53.3% 0.382 M 23.7%
14 3.469 M 2.800 M 80.7% 1.987 M 57.3%
15 3.311 M 2.285 M 69.0% 1.452 M 43.8%
25 2.389 M 1.538 M 64.4% 0.578 M 24.2%
And to make it even worse in terms of real competition, 3 of the 10
"box" scores for Zone 3 were LOW POWER entrants. Any ideas here? Are
W6 ordinances so restrictive and so widespread that nobody has any
antennas? Was EVERYBODY on a DxPedition? Come on W6 contest clubs,
let's get some local activity going. You only need 23% of the top
score to make the box!
And what about Zone 4 (lots of room and big open spaces there). A
Zone 4 guy only needed 30% of the top score to make the box!
I know I have my unavoidable EAST COAST bias, but I think that in doing
this type of comparison, I have objectively negated that slant. From a
marketing point of view, this is VERY SAD and forebodes our demise!
Come on you "little pistols" and contest clubs. Stir up the troops,
get on in the contest, and SEND IN YOUR LOG. You CAN make the BOX!
de Doug KR2Q at mcimail.com
>From Jim Hollenback" <jholly at hposl62.cup.hp.com Fri Nov 17 15:50:15 1995
From: Jim Hollenback" <jholly at hposl62.cup.hp.com (Jim Hollenback)
Date: Fri, 17 Nov 1995 07:50:15 -0800
Subject: ETO to be Acquired
References: <30ACB9B2 at msgate.pria.com>
Message-ID: <9511170750.ZM29608 at hpwsmjh1.cup.hp.com>
On Nov 17, 8:33am, KAY, LEONARD wrote:
>
> Hey, does that mean direct Alpha pick-up for 1-land now? :-)
>
Or does this mean we won't be able to bash ETO amps anymore?
73, Jim
>From km9p at is.net (Bill Fisher, KM9P Concentric Systems, Inc.) Fri Nov 17 16:49:15 1995
From: km9p at is.net (Bill Fisher, KM9P Concentric Systems, Inc.) (Bill Fisher, KM9P Concentric Systems, Inc.)
Date: Fri, 17 Nov 1995 11:49:15 -0500
Subject: WHERE'S THE BEEF?
Message-ID: <199511171649.LAA10642 at mail1.is.net>
>I know I have my unavoidable EAST COAST bias, but I think that in doing
>this type of comparison, I have objectively negated that slant. From a
>marketing point of view, this is VERY SAD and forebodes our demise!
It's interesting to see a perspective on zone 4 and zone 3 folks from
someone that has obviously never operated a a contest from disadvantaged
position.
"You expect me to believe that you have to search and pounce for 36 of 48
hours from out there? Ya right!"
I think what Doug is saying here is that he is looking for a place to guest
op in zone 3 or zone 4. Hey WB0O are you listening? Doug wants to come out
and show you how it's done!
73
Bill, KM9P
---
ehhhh yo Vivian... You's want to go wit me some time?
---
Bill Fisher, KM9P - Concentric Systems, Inc.
>From Steve Sacco <0006901972 at mcimail.com> Fri Nov 17 15:25:00 1995
From: Steve Sacco <0006901972 at mcimail.com> (Steve Sacco)
Date: Fri, 17 Nov 95 10:25 EST
Subject: 2 Antenna Queries...
Message-ID: <35951117152553/0006901972DC3EM at MCIMAIL.COM>
-- [ From: Steve Sacco KC2X * EMC.Ver #2.5.03 ] --
I've had these questions in the back of my mind for a long
time now, and have not been able to find the answer in any
of the antenna books, or here on the reflector.
(Actually, perhaps I have, but was too ignorant to realize
it)
QUESTION #1
===========
When I see a calculated number for the impedance of an
antenna (specifically, I'm thinking of the numbers generated
by a Yagi-Uda modeling program), it generates tables of numbers that look something like: "41.00 + j2.25".
>From the software doc, I see that the "41.00" number is the
Radiation Resistance (I'll call it "Rr").
Now, I've seen the definition of Rr, and I understand that
the higer the Rr, the more power the antenna is radiating.
Presuming that I have this fact correct, I then wonder this:
if I model another antenna, and it's Rr is calculated to
be: 19.29 -j8.34, does this mean that it is accepting only
about HALF of the power of the first antenna? In other
words, does antenna #1 have a 3dB advantage right off the
bat, even BEFORE the gain is calculated?
QUESTION #2
===========
This question concerns how to model LARGE vertical stacks of
antennas.
I have read somewhere in the dozen or so antenna books I
have laying around here that there is a sigificant difference in the patterns between, say, a four-high stack of Yagis which are all fed in phase with equal lengths of
feedline, and the same four-high stack which is broken up into, say, the top two antennas fed in phase, and the bottom two antennas fed in phase, and then the two feedlines which
result in those phasings being fed in phase.
As I said, I've seen reference to that fact that there's a
difference, but I've never seen any examples of what those
differences might look like.
When stacking antennas, the Yagi modeling program I use asks for the height of each antenna (of course) but also the
current in %, and the phase relative to "antenna #1". It
seems to me that this is the area of the program that would
be manipulated to come up with the "stack of stacks" answer,
but I have not got a clue as to what to tell it.
I should have studied harder in school, and been an
engineer.
Thanks for your help.
73,
Steve KC2X
ssacco at mcimail.com
** I love the smell of hot amplifiers in the morning!
It smells like....VICTORY! **
>From Douglas S. Zwiebel" <0006489207 at mcimail.com Fri Nov 17 16:18:00 1995
From: Douglas S. Zwiebel" <0006489207 at mcimail.com (Douglas S. Zwiebel)
Date: Fri, 17 Nov 95 11:18 EST
Subject: BEEF stew clarifer
Message-ID: <54951117161845/0006489207PK3EM at MCIMAIL.COM>
Hi guys....I have received a couple replies about my comparison and
based on those replies, I guess I did NOT make clear WHAT I am
comparing.
1) I am NOT comparing the SCORES from one zone to another zone.
2) I AM comparing, on a RELATIVE SCALE, what it take WITHIN ONE ZONE,
to make the active zone box. How did the 10th place guy IN THAT
ZONE do compared to the first place guy IN THAT SAME ZONE.
3) Using these RELATIVE percentages, I am saying that there is less
COMPETITION (not less ability, nor less absolute score) within
certain zones.
4) I want to know why there less COMPETITION (comparing 1st to 10th)
WITHIN THAT ZONE.
5) The percentages apply to that line (zone) only. There is NO inter-
zone comparison shown. Everything listed percentage-wise is
INTRAzone.
6) Because I am doing INTRAzone comparisons, I felt that I had negated
my "east coast" bias.
Sorry for the confusion I caused to those who did not fully comprehend
my original intention. I trust that this will clarify the TABLE I posted,
and the question(s) I am trying to find an answer to.
de Doug KR2Q at mcimail.com
>From RUSSELL S. RINN" <miltex at bga.com Fri Nov 17 17:55:13 1995
From: RUSSELL S. RINN" <miltex at bga.com (RUSSELL S. RINN)
Date: Fri, 17 Nov 1995 11:55:13 -0600 (CST)
Subject: WHERE'S THE BEEF?
Message-ID: <199511171755.LAA07538 at zoom.bga.com>
Quoting KR2Q:
> And to make it even worse in terms of real competition, 3 of the 10
> "box" scores for Zone 3 were LOW POWER entrants. Any ideas here? Are
> W6 ordinances so restrictive and so widespread that nobody has any
> antennas? Was EVERYBODY on a DxPedition? Come on W6 contest clubs,
> let's get some local activity going. You only need 23% of the top
> score to make the box!
>
> And what about Zone 4 (lots of room and big open spaces there). A
> Zone 4 guy only needed 30% of the top score to make the box!
>
Perhaps what this means is that many zone 3 and zone 4 stations do not
like to operate DX contests.
I believe I have seen many comments in the past about stations in
different parts of the country being optimized for different contests.
Those on the East Coast favoring the DX contests while those west of the
Mississippi preferring domestic contests. (Of course there are plenty of
folks around the country who enjoy both).
I also remember reading a thread some months back about why there are not
more 1's, 2's and 3's in the Sprint. I think the same theory applies.
73 and GL to everyone in SS and CQWW CW,
Russ--
Russell Rinn
AA5RB
miltex at bga.com
>From oo7 at astro.as.utexas.edu (Derek Wills) Fri Nov 17 18:41:46 1995
From: oo7 at astro.as.utexas.edu (Derek Wills) (Derek Wills)
Date: Fri, 17 Nov 1995 12:41:46 -0600
Subject: ETO to be Acquired
>Today's Wall Street Journal carries the story that Ehrhorn
>Technological Operations Inc. (ETO) has signed a letter of
>intent to be acquired by Aplied Science & Technology Inc.
>of Woburn MA for $17.5 million 70% in cash and the rest in
>stock).
That'a a lot of cash. For just 1% of that, ETO could pay off the
Heard Island boat debt and fund another expedition there as well!
That would be better PR for them than those stories of their amps
croaking on DXpeditions.
Wickedly,
Derek AA5BT, G3NMX
oo7 at astro.as.utexas.edu
>From N6IP Bob Wolbert" <n6ip at espmail.com Fri Nov 17 10:29:01 1995
From: N6IP Bob Wolbert" <n6ip at espmail.com (N6IP Bob Wolbert)
Date: Fri, 17 Nov 95 10:29:01
Subject: TS-930/940 and 2nd Antenna
Message-ID: <9510178166.AA816632941 at espmail.email.com>
I've had e-mail problems the past week or so, and did not catch the begining of
this thread.... I apologize if my hint is already "known".
I also needed a second receive antenna input for my (new-but-used) TS-930.
Unfortunately, the connector (8-pin DIN) was broken (or maybe I broke it--
seeing N4ZR and AD1C's postings about it being non-standard) so the plug did
not fit. Regardless of the status of this connector, using it would have been a
problem anyway because of its awkward size and "non-standardishness", etc.
Instead, I used the Second Receiver phono jack, located to the left of the
8-pin DIN, and the adjacent slide switch. I rewired these so that instead of
routing the antenna out to a different receiver, the slide switch now selects
between the transmit antenna and a second receive-only antenna.
I have found this simple mod very useful. The biggest problem with it is that
finding the tiny slide switch with my fingers on the bottom rear panel of the
930 is a bit difficult. Also, I now cannot use a VHF transverter either (BFD?).
BTW, this mod will also work on the TS-940, which uses the same connectors and
switching scheme.
The separate RX antenna connector also makes it easier to implement full-QSK.
73 & GL de Bob, N6IP
______________
N4ZR wrote:
>The commonly available 8-pin DIN plug has a keyway that is said to be a
>different size than that on the jack on the TS-930, 430 and 440. It is
>reportedly quite easy to break the socket if you try to plug in the generic
>plug, and a real bear to replace.
AD1C wrote:
The real difference is that the CORRECT connector has the pins arranged in
a horseshoe pattern.....<snip>
73 - Jim AD1C
>From Tim Coad" <Tim_Coad at smtp.svl.trw.com Fri Nov 17 19:09:35 1995
From: Tim Coad" <Tim_Coad at smtp.svl.trw.com (Tim Coad)
Date: 17 Nov 1995 11:09:35 -0800
Subject: WHERE'S THE BEEF?
Message-ID: <n1395515750.56738 at smtp.svl.trw.com>
Reply to: RE>WHERE'S THE BEEF?
Yes, your observation is correct. There is a lack of competition out here in
DX contests.
There is very little interest from the top ops operating from W6 land.
If any one knows this, I do. I have won the ARRL Western Region and CQ zone 3
many times from an "OK" contest station. I know its not because I am the best
op this side of the Mississippi. Its because most of the great ops out here
either enter the contest as a single band entry, go to an island somewhere,
do it for fun at a multi-multi or stick to a contest they can compete at such
as WPX or SS.
Its not from a lack of skill base. The contest club out here has at least 30
ops that could make the top ten if they operated from the east coast. No
problem.
(You have one of our old members out there now signing /1)
Is the problem propagation? Is it the contest scoring rules? Is it because
being a W6 in a DX contest is almost as boring as watching the OJ trial?
You will have to ask them.
One thing for sure though, just making it into a box score listing is
obviously not what these ops are looking for.
(But I, for one, am very glad that QST and CQ mag have started including these
boxes)
73
Tim - NU6S
--------------------------------------
Date: 11/17/95 7:14 AM
To: Tim Coad
From: Douglas S. Zwiebel
I'm sitting here looking over my October 1995 CQ magazine on page 118;
you know, the ACTIVE ZONES box. I find it really amazing at what it
(doesn't) take to make some of these boxes and, more specifically,
how little competition there is in zones 3 & 25. Take a look at these
comparisons:
ZONE top score 5th score % of #1 10th score % of #1
5 4.037 M 3.177 M 78.7% 2.317 M 57.4%
4 2.021 M 1.496 M 74.0% 0.607 M 30.0%
3 1.611 M 0.859 M 53.3% 0.382 M 23.7%
14 3.469 M 2.800 M 80.7% 1.987 M 57.3%
15 3.311 M 2.285 M 69.0% 1.452 M 43.8%
25 2.389 M 1.538 M 64.4% 0.578 M 24.2%
And to make it even worse in terms of real competition, 3 of the 10
"box" scores for Zone 3 were LOW POWER entrants. Any ideas here? Are
W6 ordinances so restrictive and so widespread that nobody has any
antennas? Was EVERYBODY on a DxPedition? Come on W6 contest clubs,
let's get some local activity going. You only need 23% of the top
score to make the box!
And what about Zone 4 (lots of room and big open spaces there). A
Zone 4 guy only needed 30% of the top score to make the box!
I know I have my unavoidable EAST COAST bias, but I think that in doing
this type of comparison, I have objectively negated that slant. From a
marketing point of view, this is VERY SAD and forebodes our demise!
Come on you "little pistols" and contest clubs. Stir up the troops,
get on in the contest, and SEND IN YOUR LOG. You CAN make the BOX!
de Doug KR2Q at mcimail.com
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From: "Douglas S. Zwiebel" <0006489207 at mcimail.com>
Reply-To: "Douglas S. Zwiebel" <0006489207 at mcimail.com>
To: Contesters <cq-contest at tgv.com>
Subject: WHERE'S THE BEEF?
Message-Id: <10951117145501/0006489207PK1EM at MCIMAIL.COM>
>From kaufmann at ll.mit.edu (John Kaufmann) Fri Nov 17 19:36:42 1995
From: kaufmann at ll.mit.edu (John Kaufmann) (John Kaufmann)
Date: Fri, 17 Nov 95 14:36:42 -0500
Subject: 2 Antenna Queries...
Message-ID: <9511171436.AA11043 at LL.MIT.EDU>
>-- [ From: Steve Sacco KC2X * EMC.Ver #2.5.03 ] --
>
>I've had these questions in the back of my mind for a long
>time now, and have not been able to find the answer in any
>of the antenna books, or here on the reflector.
>(Actually, perhaps I have, but was too ignorant to realize
>it)
>
>QUESTION #1
>===========
>When I see a calculated number for the impedance of an
>antenna (specifically, I'm thinking of the numbers generated
>by a Yagi-Uda modeling program), it generates tables of numbers that look
something like: "41.00 + j2.25".
>From the software doc, I see that the "41.00" number is the
>Radiation Resistance (I'll call it "Rr").
>
>Now, I've seen the definition of Rr, and I understand that
>the higer the Rr, the more power the antenna is radiating.
>Presuming that I have this fact correct, I then wonder this:
>if I model another antenna, and it's Rr is calculated to
>be: 19.29 -j8.34, does this mean that it is accepting only
>about HALF of the power of the first antenna? In other
>words, does antenna #1 have a 3dB advantage right off the
>bat, even BEFORE the gain is calculated?
>
>
Antenna #1 would have a 3 dB advantage only if the currents driving
the two antennas were the same (Power = I^2 R). However, in
practice, real radio transmitters/amplifiers deliver constant
power (not current) output into reasonable loads, i.e. loads that
can be matched with the transmitter output matching network. Therefore,
the total powers radiated by the two antennas are the same, regardless of
the antenna impedances, assuming there is no other loss in the antennas.
>QUESTION #2
>===========
>This question concerns how to model LARGE vertical stacks of
>antennas.
>
>I have read somewhere in the dozen or so antenna books I
>have laying around here that there is a sigificant difference in the
patterns between, say, a four-high stack of Yagis which are all fed in phase
with equal lengths of
>feedline, and the same four-high stack which is broken up into, say, the
top two antennas fed in phase, and the bottom two antennas fed in phase, and
then the two feedlines which
>result in those phasings being fed in phase.
>
>As I said, I've seen reference to that fact that there's a
>difference, but I've never seen any examples of what those
>differences might look like.
If the 4 antennas are truly identical and are fed with equal magnitude, in-phase
currents, then the gain and pattern is independent of how the antennas are fed.
However, in the real world, it is hard to come up with four electrically
identical antennas in a stack, even if they are mechanically the same. For
one thing, the effects of ground proximity and mutual coupling to the other
antennas in the stack are different for each antenna. For example, the
middle antennas couple to antennas above and below, whereas the top and bottom
ones do not. In practice this makes it harder to get the currents to divide
equally between non-identical loads. How the individual antennas are
fed can make a difference in this case, but will depend on the specifics
of the antenna setup. These effects can be modeled with some of the existing
antenna modeling software.
>
>When stacking antennas, the Yagi modeling program I use asks for the height
of each antenna (of course) but also the
>current in %, and the phase relative to "antenna #1". It
>seems to me that this is the area of the program that would
>be manipulated to come up with the "stack of stacks" answer,
>but I have not got a clue as to what to tell it.
The "ideal" current magnitudes and phases depend on many things, including
the antenna spacing, the height above ground, the radiation angles of
interest, the desired off-axis rejection, etc., etc....There is no simple
universally optimal solution.
>
>I should have studied harder in school, and been an
>engineer.
>
>Thanks for your help.
>
>73,
>Steve KC2X
>ssacco at mcimail.com
73,
John Kaufmann W1FV
kaufmann at ll.mit.edu
>From aa4lr at radio.org (Bill Coleman AA4LR) Fri Nov 17 18:46:21 1995
From: aa4lr at radio.org (Bill Coleman AA4LR) (Bill Coleman AA4LR)
Date: Fri, 17 Nov 1995 14:46:21 -0400
Subject: Bounced off list
Message-ID: <v01520d09acd288a3c9a8@[205.160.29.40]>
Hmm. I wondered why I hadn't seen any cq-contest messages in a couple of
days. So, I sent a query to the cq-contest-request address. It came back
indicating I wasn't on the list!
I've now re-subscribed. Did this happen to anyone else?
Bill Coleman, AA4LR Mail: aa4lr at radio.org
Quote: "The same light shines on vineyards that makes deserts." -- Steve
Hackett
>From jbwolf at most.magec.com (James B. Wolf ) Fri Nov 17 19:46:25 1995
From: jbwolf at most.magec.com (James B. Wolf ) (James B. Wolf )
Date: Fri, 17 Nov 1995 14:46:25 -0500
Subject: 2 Antenna Queries...
Message-ID: <9511171952.AA08523 at ss4.uiv>
Steve
I'll take a stab at your questions.
>When I see a calculated number for the impedance of an
>antenna (specifically, I'm thinking of the numbers generated
>by a Yagi-Uda modeling program), it generates tables of numbers that look
something like: "41.00 + j2.25".
>>From the software doc, I see that the "41.00" number is the
>Radiation Resistance (I'll call it "Rr").
>
>Now, I've seen the definition of Rr, and I understand that
>the higer the Rr, the more power the antenna is radiating.
>Presuming that I have this fact correct, I then wonder this:
>if I model another antenna, and it's Rr is calculated to
>be: 19.29 -j8.34, does this mean that it is accepting only
>about HALF of the power of the first antenna? In other
>words, does antenna #1 have a 3dB advantage right off the
>bat, even BEFORE the gain is calculated?
Radiations resistance is the resistive part of coupling to an antenna and
the objects around it, usually ground.
It is the resistance that is measured at the point of maximum current in an
antenna ( usually the feedpoint ),
assuming no resistive losses. Not knowing what program you are using, I am
not sure what it is giving you for
an impedance. Most programs calculate the impedance of an antenna over
perfect ground.
The problem with low antenna impedances can be two-fold. 1. The lower the
impedance, the higher the current,
which means the higher the ohmic losses in the antenna material. 2.
Matching to the lower impedance for the
same reason discussed in number 1.
Assuming that a 50 ohm source is feeding a 50 ohm antenna there is 100%
power transfer, assuming no ohmic losses.
If a 50 ohm source is feeding a 12.5 ohm antenna through a 4:1 transformer,
you will still have 100% power
transfer. This is typically the situation on high gain VHF/UHF yagis. A 50
ohm source feeding a 12.5 ohm antenna
through some kind of matching device to transform it to 50 ohms.
So, your antenna #1 would not have 3 dB more gain because its impedance is
different, ohmic losses aside.
>QUESTION #2
>===========
>This question concerns how to model LARGE vertical stacks of
>antennas.
>
>I have read somewhere in the dozen or so antenna books I
>have laying around here that there is a sigificant difference in the
patterns between,
>say, a four-high stack of Yagis which are all fed in phase with equal
lengths of
>feedline, and the same four-high stack which is broken up into, say, the
top two antennas
>fed in phase, and the bottom two antennas fed in phase, and then the two
feedlines which
>result in those phasings being fed in phase.
No difference. If the antennas are fed with the same phase component they
will act the same, no matter how
you got there. For a four high stack, Unless you are trying force a heigher
angle, all antennas normally
would be fed with the same phase. Zero is popular with me.
>When stacking antennas, the Yagi modeling program I use asks for the height
of each antenna (of course) but also the
>current in %, and the phase relative to "antenna #1". It
>seems to me that this is the area of the program that would
>be manipulated to come up with the "stack of stacks" answer,
>but I have not got a clue as to what to tell it.
Normally, the only array that would be fed with different phase angles would
be vertical arrays.
In a four high stack all the antennas should be fed with the same current,
voltage and phase.
GL-Jim, KR9U
--------------------------------------
James B. Wolf Phone:219-429-4638
Mail Stop:25-71 Fax:8215 Email: jbwolf at most.fw.hac.com
MESC, 1313 Production Road, Fort Wayne, IN 46808
>From gaudier at new-york.sl.slb.com (Dale Gaudier) Fri Nov 17 20:56:23 1995
From: gaudier at new-york.sl.slb.com (Dale Gaudier) (Dale Gaudier)
Date: Fri, 17 Nov 1995 15:56:23 -0500
Subject: Digital Voice Keyer/Sound Blaster
Message-ID: <v02130503acd26127f6a6@[163.185.35.173]>
Anyone out there in contest land know of sources for software which would
allow me to use my Sound Blaster board and computer hard drive as a digital
voice keyer for contesting?
73 and see you in SS this weekend.
Dale
Dale Gaudier - N4REE/1 Darien, CT
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