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[Towertalk] 20M Yagi ?

To: <towertalk@contesting.com>
Subject: [Towertalk] 20M Yagi ?
From: WD4K_1@Bellsouth.net (WD4K)
Date: Mon, 15 Jul 2002 13:50:07 -0600
Considering the recent discussion of the OWA, before planning this project I
need some opinions. I have my main 110'Rohn 55 tower filled up and going up
now but want an excellent performing 20M yagi on a second tower. The 2nd
tower and hardware, rotor etc are here. I have up to 125' of Rohn 25 to work
with. I would prefer to keep it under 75' and think that in this location,
the 55-75' height would be just fine. Modeling help needed here also. Now to
what to build. I have an extensive aluminum boneyard so I probably have a
good amount of the necessary materials. OWA design, other designs, ???  The
qth here is on an 800' hilltop with 200-300' drop and horizon in the three
main directions. Any suggestions before I start planning this next project?
Thanks, Tommy WD4K

-----Original Message-----
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towertalk-request@contesting.com
Sent: Monday, July 15, 2002 9:11 AM
To: towertalk@contesting.com
Subject: Towertalk digest, Vol 1 #356 - 13 msgs


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Today's Topics:

   1. Re: ginpole redux (Stan & Patricia Griffiths)
   2. Re: Comparison!! (Larry Bush)
   3. HAZER and ROHN 25G tower (N29219963@cs.com)
   4. Re: [Antennas] Comparison!! (Eric Lemmon)
   5. Re: Re: [Antennas] Comparison!! (Sherman Leifer)
   6. Re: [Amps] Mica Capacitors (Pete Smith)
   7. Re: Guy Wire Tensioning-WAS Lost My Tower (Pete Smith)
   8. Re: Guy Wire Tensioning-WAS Lost My Tower (Stan & Patricia Griffiths)
   9. Belden P/N 008-0126089 what is it? (Mike Allisette)
  10. Re: antenneX's Compact Antenna Book Release (K7LXC@aol.com)
  11. Re: HAZER and ROHN 25G tower - WARNING (K7LXC@aol.com)
  12. RE: Re: antenneX's Compact Antenna Book Release (Dale L Martin)
  13. =?iso-8859-1?Q?Re:_[Towertalk]_OWA_Yagis?=
(=?iso-8859-1?Q?i4jmy@iol.it?=)

--__--__--

Message: 1
From: "Stan & Patricia Griffiths" <w7ni@easystreet.com>
To: "Towertalk" <towertalk@contesting.com>, "jljarvis"
<jljarvis@adelphia.net>
Subject: Re: [Towertalk] ginpole redux
To: <towertalk@contesting.com>
Date: Sat, 13 Jul 2002 18:26:22 -0700

I rig like that all the time and it can be done with a Rohn gin pole.  You
just have to ignore the pulley that Rohn provides and get a double pulley
for the top of your block and tackle with a hook on it and place the hook
over the top of the gin pole.

Stan
w7ni@easystreet.com

----- Original Message -----
From: "jljarvis" <jljarvis@adelphia.net>
To: <towertalk@contesting.com>
Sent: Friday, July 12, 2002 12:33 AM
Subject: [Towertalk] ginpole redux


>
> kk1l observed that I wasn't thinking clearly, with
> respect to possible pulley scenarios and ginpole loads.
> It IS possible to reduce the load on the pole, by using
> a 2 part tackle on the LOAD side of the ginpole:
>
> >
> >    O  T fixed to top of pole 150# total
> >   | | |
> >   | | |
> >   | | |
> >   |  O
> >   |  V
> >   |  LOAD 100#
> >   |
> >   |
> >   V
> >  50#
>
> Now comes the question...anybody see a way to actually RIG a
> pole like that?  The rohn top casting/block doesn't provide
> an easy way.  A through-bolt would get in the way of the
> LIFT line, in the pole.  The fixed line, at 't', would have to
> be fastened to a clamp of some sort.
>
> Jim/N2EA
> _______________________________________________
> Self Supporting Towers, Wireless Weather Stations, see web site:
http://www.mscomputer.com
> Call 888-333-9041 to place your order, mention you saw this ad and take an
additional 5 percent off
> any weather station price.
> _______________________________________________
> Towertalk mailing list
> Towertalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>


--__--__--

Message: 2
Reply-To: "Larry Bush" <w5ncd@bigfoot.com>
From: "Larry Bush" <lbush@hot.rr.com>
To: <antennas@mailman.qth.net>, "Sherman Leifer" <sherman@mscomputer.com>
Cc: <towertalk@contesting.com>
Subject: Re: [Towertalk] Comparison!!
To: <towertalk@contesting.com>
Date: Sat, 13 Jul 2002 11:18:37 -0500

The Celwave is fine antenna but when hit by lightning it will blow all to
pieces. If you want lightning protection the DB-616 is the antenna of
choice.

Larry, W5NCD


----- Original Message -----
From: "Sherman Leifer" <sherman@mscomputer.com>
To: <antennas@mailman.qth.net>
Cc: <towertalk@contesting.com>
Sent: Saturday, July 13, 2002 10:34 AM
Subject: [Towertalk] Comparison!!


> Does anyone out there have experience with the following antennas and can
> give me their opinion of both for repeater and base use.
>
> Celwave Super Stationmaster
> DB Products Model DB616
>
> Both are for two meters and appear to have similar specifications.  I am
> looking for an opinion as to which one will stand up better to lighting
and
> harsh winter weather with lots of wind and possible ice.
>
> Thanks Much!!
>
> Sherman
> W2FLA
>
>
>
> Web sites owned and operated by M&S Computer
>
> http://www.mscomputer.com             Your "one" stop for all your
Computer
> Needs.
> http://www.servers4networks.com      The only place to go for a Network
> File Server Computer System.
> http://www.tonerrefill.com                  Save $$$$$$ on all HP Laser
> Toner Cartridges.
> http://www.wirelessweatherstation.com Fantastic  Wireless Weather Station
> Only $399.95
> http://www.towerdepot.com               The best 20-100 foot Self
> Supporting Communications Tower.
> http://www.usaleatherjacket.com         Leather Jacket with USA on sleeves
> and USA Flag on back!
>
> Phone:                  800-333-9041 (USA Only)
> Phone:                    973-263-9041
> Fax:                        973-316-0653
> Technical Support: 973-299-1000
>
> --- StripMime Report -- processed MIME parts ---
> multipart/alternative
>   text/plain (text body -- kept)
>   text/html
> ---
> _______________________________________________
> Self Supporting Towers, Wireless Weather Stations, see web site:
http://www.mscomputer.com
> Call 888-333-9041 to place your order, mention you saw this ad and take an
additional 5 percent off
> any weather station price.
> _______________________________________________
> Towertalk mailing list
> Towertalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk


--__--__--

Message: 3
From: N29219963@cs.com
To: <towertalk@contesting.com>
Date: Sat, 13 Jul 2002 15:16:38 EDT
To: towertalk@contesting.com
Subject: [Towertalk] HAZER and ROHN 25G tower

 I have a 25G tower 55 ft high . I would like to know is I can use a HAZER 4
when I have Guys of 7/32 in dia. nylon rope at 38 ft ? Could I pass then
behind the Hazer before raising ? Will there be clearance ?
Walt W3ZAC
Email  n29219963@cs.com

--__--__--

Message: 4
To: <towertalk@contesting.com>
Date: Sat, 13 Jul 2002 19:28:07 -0700
From: Eric Lemmon <elemmon@impulse.net>
To: Sherman Leifer <sherman@mscomputer.com>
CC: antennas@mailman.qth.net, towertalk@contesting.com
Subject: [Towertalk] Re: [Antennas] Comparison!!

Sherman,

A proper answer to your question must consider WHICH "Super Stationmaster"
antenna you are comparing to the DB616.  If the choice was between the DB616
and the PD220-2 Super Stationmaster, I would choose the DB616.  But, if the
choice was between the DB616 and the PD620-2 Super Stationmaster, I would
choose the PD620-2.

The Celwave catalog identifies both the PD220 and the PD620 series antennas
as
"Super Stationmaster" but notes that the PD620 series is an "extra-rugged"
version of the PD220.  Among the differences are a 3.5 inch base diameter
versus 2.75 inches, and the fiberglass radome is thicker, larger, and much
stronger.  It's also VERY expensive!  Choose wisely...

73, Eric Lemmon WB6FLY

Sherman Leifer wrote:

> Does anyone out there have experience with the following antennas and can
> give me their opinion of both for repeater and base use.
>
> Celwave Super Stationmaster
> DB Products Model DB616
>
> Both are for two meters and appear to have similar specifications.  I am
> looking for an opinion as to which one will stand up better to lighting
and
> harsh winter weather with lots of wind and possible ice.
>
> Thanks Much!!
>
> Sherman
> W2FLA
>
> Web sites owned and operated by M&S Computer
>
> http://www.mscomputer.com             Your "one" stop for all your
Computer
> Needs.
> http://www.servers4networks.com      The only place to go for a Network
> File Server Computer System.
> http://www.tonerrefill.com                  Save $$$$$$ on all HP Laser
> Toner Cartridges.
> http://www.wirelessweatherstation.com Fantastic  Wireless Weather Station
> Only $399.95
> http://www.towerdepot.com               The best 20-100 foot Self
> Supporting Communications Tower.
> http://www.usaleatherjacket.com         Leather Jacket with USA on sleeves
> and USA Flag on back!
>
> Phone:                  800-333-9041 (USA Only)
> Phone:                    973-263-9041
> Fax:                        973-316-0653
> Technical Support: 973-299-1000
>
> --- StripMime Report -- processed MIME parts ---
> multipart/alternative
>   text/plain (text body -- kept)
>   text/html
> The reason this message is shown is because the post was in HTML
> or had an attachment. Attachments are not allowed.
> Please post in Plain-Text only.---
> - - -
>
> Your moderator for this list is:
> Larry Wilson KE1HZ antennas-owner@mailman.qth.net
> _______________________________________________
> Antennas mailing list
> Antennas@mailman.qth.net
> http://mailman.qth.net/mailman/listinfo/antennas



--__--__--

Message: 5
To: <towertalk@contesting.com>
Date: Sun, 14 Jul 2002 13:50:28 -0400
To: towertalk@contesting.com
From: Sherman Leifer <sherman@mscomputer.com>
Subject: Re: [Towertalk] Re: [Antennas] Comparison!!
Cc: antennas@mailman.qth.net

I would just like to thank everyone who had replied to my question.

As I thought the Celwave Super Stationmaster appears to be the winner.  The
model is the PD620, which is the heavy duty version of the two
"Stationmaster" antennas Celwave manufacturers.

My plans are to put one at the top of my 110 foot rotation tower (see
http://www.w2fla.com) .  With the property at over 2000 feet above sea
level on top of this mountain, it should work gang busters.  I am also
going two install (2) Cubex 8 element 2 meter quads (vertically stacked) at
the 80-90 foot mark for pin point communications.  Of course I will use all
hard line and a switch box on the tower to switch between antennas.  The
hard line is necessary since the tower is 300 feet behind the house.  So
any of you guys in VK or ZL land make sure you listen for me on 146.52 very
soon.

Again, thanks to all who gave me their opinion.

73
Sherman
W2FLA
Formally W4FLA








At 07:28 PM 7/13/02 -0700, you wrote:
>Sherman,
>
>A proper answer to your question must consider WHICH "Super Stationmaster"
>antenna you are comparing to the DB616.  If the choice was between the
DB616
>and the PD220-2 Super Stationmaster, I would choose the DB616.  But, if the
>choice was between the DB616 and the PD620-2 Super Stationmaster, I would
>choose the PD620-2.
>
>The Celwave catalog identifies both the PD220 and the PD620 series antennas
as
>"Super Stationmaster" but notes that the PD620 series is an "extra-rugged"
>version of the PD220.  Among the differences are a 3.5 inch base diameter
>versus 2.75 inches, and the fiberglass radome is thicker, larger, and much
>stronger.  It's also VERY expensive!  Choose wisely...
>
>73, Eric Lemmon WB6FLY
>
>Sherman Leifer wrote:
>
> > Does anyone out there have experience with the following antennas and
can
> > give me their opinion of both for repeater and base use.
> >
> > Celwave Super Stationmaster
> > DB Products Model DB616
> >
> > Both are for two meters and appear to have similar specifications.  I am
> > looking for an opinion as to which one will stand up better to lighting
and
> > harsh winter weather with lots of wind and possible ice.
> >
> > Thanks Much!!
> >
> > Sherman
> > W2FLA
> >
> > Web sites owned and operated by M&S Computer
> >
> > http://www.mscomputer.com             Your "one" stop for all your
Computer
> > Needs.
> > http://www.servers4networks.com      The only place to go for a Network
> > File Server Computer System.
> > http://www.tonerrefill.com                  Save $$$$$$ on all HP Laser
> > Toner Cartridges.
> > http://www.wirelessweatherstation.com Fantastic  Wireless Weather
Station
> > Only $399.95
> > http://www.towerdepot.com               The best 20-100 foot Self
> > Supporting Communications Tower.
> > http://www.usaleatherjacket.com         Leather Jacket with USA on
sleeves
> > and USA Flag on back!
> >
> > Phone:                  800-333-9041 (USA Only)
> > Phone:                    973-263-9041
> > Fax:                        973-316-0653
> > Technical Support: 973-299-1000
> >
> > --- StripMime Report -- processed MIME parts ---
> > multipart/alternative
> >   text/plain (text body -- kept)
> >   text/html
> > The reason this message is shown is because the post was in HTML
> > or had an attachment. Attachments are not allowed.
> > Please post in Plain-Text only.---
> > - - -
> >
> > Your moderator for this list is:
> > Larry Wilson KE1HZ antennas-owner@mailman.qth.net
> > _______________________________________________
> > Antennas mailing list
> > Antennas@mailman.qth.net
> > http://mailman.qth.net/mailman/listinfo/antennas
>
>
>_______________________________________________
>Self Supporting Towers, Wireless Weather Stations, see web site:
>http://www.mscomputer.com
>Call 888-333-9041 to place your order, mention you saw this ad and take an
>additional 5 percent off
>any weather station price.
>_______________________________________________
>Towertalk mailing list
>Towertalk@contesting.com
>http://lists.contesting.com/mailman/listinfo/towertalk



Web sites owned and operated by M&S Computer

http://www.mscomputer.com             Your "one" stop for all your Computer
Needs.
http://www.servers4networks.com      The only place to go for a Network
File Server Computer System.
http://www.tonerrefill.com                  Save $$$$$$ on all HP Laser
Toner Cartridges.
http://www.wirelessweatherstation.com Fantastic  Wireless Weather Station
Only $399.95
http://www.towerdepot.com               The best 20-100 foot Self
Supporting Communications Tower.
http://www.usaleatherjacket.com         Leather Jacket with USA on sleeves
and USA Flag on back!

Phone:                  800-333-9041 (USA Only)
Phone:                    973-263-9041
Fax:                        973-316-0653
Technical Support: 973-299-1000

--- StripMime Report -- processed MIME parts ---
multipart/alternative
  text/plain (text body -- kept)
  text/html
---

--__--__--

Message: 6
To: <towertalk@contesting.com>
Date: Sun, 14 Jul 2002 14:50:32 -0400
To: towertalk@contesting.com
From: Pete Smith <n4zr@contesting.com>
Subject: [Towertalk] Re: [Amps] Mica Capacitors

At 12:23 PM 7/14/02 -0400, Tom Rauch wrote on the Amps reflector:
>The mica caps used in old sets like that are very good RF capacitors.
>They are conservatively rated, so you can push them over the rating
>by a reasonable margin.
>
>You probably are safe up to about 3000 volts RMS, unless you want to
>be sure to have 100% no failures ever.

Conversely, would I be safe in assuming that the EIA Class 2 3000V-rated
disk ceramics in, for example, Mouser's catalogue (10% Y5P temperature
coeff.), would be usable, for example, as compensating caps in UNUN
transformer usage, with amateur power levels, at 50 or 75 ohms?


73, Pete N4ZR

Check out the World HF
Contest Station Database at
www.pvrc.org





--__--__--

Message: 7
To: <towertalk@contesting.com>
Date: Sun, 14 Jul 2002 16:35:20 -0400
To: towertalk@contesting.com
From: Pete Smith <n4zr@contesting.com>
Subject: Re: [Towertalk] Guy Wire Tensioning-WAS Lost My Tower

At 04:25 PM 7/13/02 -0400, K7LXC@aol.com wrote:
>In a message dated Fri, 12 Jul 2002 9:38:49 PM Eastern Standard Time,
>weightdn@adelphia.net writes:
>
> > The question of the moment is, what is a good way to grip 3/16 guy wire
> with
> > a come-along to get the initial tension on it? I plan on using preforms
on
> > the guys if that has any bearing on methods.
>
>     The easiest thing is to use one PreForm as a temporary and then
>just throw it away when you're done. Just hook the comealong to it -
>you don't have to wrap it the whole way.

Credit this one to W9LT, at my first tower-raising -- since we're talking
temporary, he just put a single cable clamp on the guy wire and then tied a
rope "above" the cable clamp with a slip knot.  Simple, positive and
cheap.  If more than hand tensioning is needed, a come-along is easy to
bring into the mix.


73, Pete N4ZR

Check out the World HF
Contest Station Database at
www.pvrc.org





--__--__--

Message: 8
From: "Stan & Patricia Griffiths" <w7ni@easystreet.com>
To: "Towertalk" <towertalk@contesting.com>, "Pete Smith"
<n4zr@contesting.com>
Subject: Re: [Towertalk] Guy Wire Tensioning-WAS Lost My Tower
To: <towertalk@contesting.com>
Date: Sun, 14 Jul 2002 13:56:39 -0700

What I have done for tensioning 1/4" EHS is to make a loop out of a short
length the same cable and cable-clamp it to the guy wire.  I then hook a
comealong into that loop and into another loop attached to the anchor.

If you want to get fancy, Klein makes some special "quick disconnect" clamps
for this very purpose.  Kinda spendy though . . .

Stan
w7ni@easystreet.com

----- Original Message -----
From: "Pete Smith" <n4zr@contesting.com>
To: <towertalk@contesting.com>
Sent: Sunday, July 14, 2002 1:35 PM
Subject: Re: [Towertalk] Guy Wire Tensioning-WAS Lost My Tower


> At 04:25 PM 7/13/02 -0400, K7LXC@aol.com wrote:
> >In a message dated Fri, 12 Jul 2002 9:38:49 PM Eastern Standard Time,
> >weightdn@adelphia.net writes:
> >
> > > The question of the moment is, what is a good way to grip 3/16 guy
wire
> > with
> > > a come-along to get the initial tension on it? I plan on using
preforms on
> > > the guys if that has any bearing on methods.
> >
> >     The easiest thing is to use one PreForm as a temporary and then
> >just throw it away when you're done. Just hook the comealong to it -
> >you don't have to wrap it the whole way.
>
> Credit this one to W9LT, at my first tower-raising -- since we're talking
> temporary, he just put a single cable clamp on the guy wire and then tied
a
> rope "above" the cable clamp with a slip knot.  Simple, positive and
> cheap.  If more than hand tensioning is needed, a come-along is easy to
> bring into the mix.
>
>
> 73, Pete N4ZR


--__--__--

Message: 9
From: "Mike Allisette" <mike.allisette@virgin.net>
To: <towertalk@contesting.com>
To: <towertalk@contesting.com>
Date: Sun, 14 Jul 2002 22:52:43 +0100
Subject: [Towertalk] Belden P/N 008-0126089 what is it?

Hi Folks

I have "acquired" a drum of belden Coax P/N 008-0126089 coax.
it has a solid inner approx 20 AWG, foam Dielectric covered with aluminium
foil covered by copper braid and finally a black PVC jacket outer diameter
is approx 7mm.

Has anyone any ideas what this is equivalent to? I've tried the Belden
Website but can't seem to match it to anything in their catalogue.

Thanks in advance

Mike Allisette GU4EON


--__--__--

Message: 10
To: <towertalk@contesting.com>
Date: Mon, 15 Jul 2002 08:04:43 -0400
From: K7LXC@aol.com
To: towertalk@contesting.com
Subject: [Towertalk] Re: antenneX's Compact Antenna Book Release

In a message dated Sun, 14 Jul 2002 11:16:11 AM Eastern Standard Time,
info@antennex.com writes:

Hello, TowerTalkians --

    Here's an announcement about a new antenna book that you may be
interested in.

Cheers,
Steve      K7LXC

> * * * * * ANNOUNCEMENT * * * * *
>
> >>> COMPACT CAPACITOR ANTENNAS <<<
>
> COMPACT CAPACITOR ANTENNAS
> This 30-chapter eBOOK of more than 215 pages is a publication by antenneX
> with a collection of papers written by some of the best and most active
> experts in the design, development and construction of compact antennas
> based on a technology, the name of which was coined at antenneX -- the
> "capacitor antenna."
>
> Without a doubt, this is one of the most unique books of its kind about a
> subject that concerns more radio operators as each day goes by-a shrinking
> operating environment!
>
> Almost without exception, the antennas presented in this book are new and
> unique all designed to produce the most HF radiation from the smallest
> device in the least amount of space. The devices described in this book
are
> taken from many years of efforts by numerous experienced engineers,
> scientists and experimenters from various parts of the Globe.
>
> This unique book is bound to become a classic collection.
> It is now
> available on CD-ROM or direct download at:
> http://www.antennex.com/Sshack/cca/cca.htm
>
> ...or visit the main menu at:
>
> http://www.antennex.com/shopping.htm
>
> Thanks for your time!
>
> Jack L. Stone, Publisher
> antenneX Online Magazine
> http://www.antennex.com
> jack@antennex.com



--__--__--

Message: 11
To: <towertalk@contesting.com>
Date: Mon, 15 Jul 2002 08:10:05 -0400
From: K7LXC@aol.com
To: N29219963@cs.com, towertalk@contesting.com
Subject: Re: [Towertalk] HAZER and ROHN 25G tower - WARNING

In a message dated Sat, 13 Jul 2002 2:16:38 PM Eastern Standard Time,
N29219963@cs.com writes:

> I have a 25G tower 55 ft high . I would like to know is I
> can use a HAZER 4
> when I have Guys of 7/32 in dia. nylon rope at 38 ft ?

    All of your Hazer questions are moot until you BRING YOUR TOWER UP TO
MANUFACTURER'S SPECS. You are in fatal violation of the LXC Prime Directive
to "DO what the manufacturer says." Ignore this at your own risk.

    Rope is NOT a suitable guy material - 3/16" EHS (extra high strength) is
the only guy material specified by the manufacturer.

    The Rohn catalog is available from www.championradio.com. Take care of
your tower structure first, then we'll talk about the Hazer.

Cheers,
Steve     K7LXC
TOWER TECH --
Professional tower services for commercial and amateur

--__--__--

Message: 12
From: "Dale L Martin" <kg5u@hal-pc.org>
To: <towertalk@contesting.com>
Subject: RE: [Towertalk] Re: antenneX's Compact Antenna Book Release
To: <towertalk@contesting.com>
Date: Mon, 15 Jul 2002 09:09:29 -0500


> >
> > Without a doubt, this is one of the most unique books of its
> kind about a
> > subject that concerns more radio operators as each day goes
> by-a shrinking
> > operating environment!
> >

'
"one of the most unique books of its kind" ?????

Are there other less "unique books of its kind" ??

Is "most unique" more unique than unique?

Inquiring minds want to know.....

73,
dale, kg5u







--__--__--

Message: 13
To: <towertalk@contesting.com>
Date: Mon, 15 Jul 2002 17:08:24 +0200
From: "=?iso-8859-1?Q?i4jmy@iol.it?=" <i4jmy@iol.it>
To: kk9a@arrl.net
Cc: towertalk@contesting.com
Subject: [Towertalk] =?iso-8859-1?Q?Re:_[Towertalk]_OWA_Yagis?=

As everyone knows it's almost impossible to set all parameters at best
in a single yagi antenna.

In my experience, the difference in gain between an optimized yagi with
good F/B over a stated boom and an OWA is within half dB.
Taking in account for matching losses when the impedance is low,
probably the half db advantage for the non OWA design further reduces
or even inverts, expecially if the peak gain of the yagi doesn't drop
where predicted, a good SWR is not a gain indicator.

Along an HF band the OWA is a very good solution to insure stable
performances within an entire band at the price of a small gain
reduction compared to the peak one of the classic yagi, but probably
giving more in terms of gain/BW and F/B, not counting the semplicity
and safe power handling of a symple 50 OHms feed compared to matching
devices that might have problems and further reduce BW.

On the other hand, when the required BW is a smaller percentage than Cf
the OWA is loosing something in pure gain, at least in theory.

One can always decide if to give up 0.3 db gain and beeing almost sure
about the obtained gain or trust narrow BW design and to obtain the
peaked gain just where it serves.

Is a mistery why hams put always so great attention to fractional
antenna gain, prone to pay for that (promised) extra, while they have
the tendency to spare money with lines where gain is frequently lost in
larger amounts.

73,
Mauri I4JMY



> Does anyone have any experience with the OWA design yagis.  Is there a
ny
> advantage other than low SWR and direct 50 ohm feed?  I modeled the 15
m 6el
> X 36' boom and compared it to my DX Engineering 15DX-
6 with the same boom
> length and the DX Engineering had more gain throughout most of the ban
d.
> Are there losses in the DX Eng. hair pin match or higher SWR that woul
d make
> the OWA come out on top?
>
> 73,
> John
>
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