Sorry, Alan .. have to disagree with you. You did not scope out my
posting.. Here the Mosely company is talking about their TRAP MASTER
beams... not their CLASSIC! Actually, I agree with what you posted as to
the way to hook up a yagi, BUT IF you are talking about the CLASSIC
design, you are "wrongo" .. AND, I have used those type in VA, CA, and AK ..
When you stuff an insulated waaarrr down the driven element, without any
mechanical connection, your hypthesis is nil....
Hey .. did you know Jack, KW6EJ? He and I chatted nightly on 2ØM, etc. in
the late 60s.... I hadda job in hand, the commisary at Wake Island, but XYL
did not want to move there with the two daughters, ready to enter school.
Please don't confuse what I posted with what others typed!
Mark .. AA6DX
----- Original Message -----
From: "Alan C. Zack" <k7acz@cox.net>
To: "AA6DX" <aa6dx@pacbell.net>
Cc: "J.Hector Garcia M" <Hector@telecom1.net>; <towertalk@contesting.com>;
"Randy" <rlake@webryders.net>; "Scott R." <w4pa@yahoo.com>
Sent: Thursday, April 29, 2004 2:52 PM
Subject: Re: [TowerTalk] Mystery Hy-Gain tribander
Mark,
I have to disagree with you. Below is the direct quote from the Mosley web
site
FAQ page:
http://www.mosley-electronics.com/faq.htm
Besides my using a Mosley at home they were used at most of the Coast Guard
LORAN stations at Kure, Wake, Johnston, Yap, Marcus, Palau, etc, etc. where
I
would operate from.
FEED SYSTEMS - THE SIMPLER, THE BETTER!
Despite popular belief, linear radiators, normally employed in 2 and
3
element
parasitic arrays, have a driving point impedance of close to 52 ohms
when open at
the center. To feed such a radiator it is only necessary to connect
a 52
ohm line at
this point to achieve the best possible match of line to antenna.
However, because of certain design characteristics, some beam
antennas
require
elaborate and, sometime, unstable matching devices such as Gamma or
T-Match
systems or variations of these systems. Such devices are usually
difficult to adjust
and to maintain in adjustment when used in multi-band beams.
MOSLEY TRAP MASTER beams, however, are so designed as to not require
any unwieldy matching arrangements. This beam is fed by connecting
the
line
directly to the open center of the radiator. Thus, an excellent
match is
achieved
over the entire width of each Ham band resulting in extremely low
SWR
near
resonant frequencies of each band and the ability to range from one
end
of the
band to the other without excessive SWR.
By eliminating such matching devices, MOSLEY TRAP MASTER beams
provide
their users with stable and dependable operation without the
necessity
of frequent
trips to the roof or up the tower to make readjustment.
As I stated previously my Mosley was designed to connect a split lead coax
directly to the driven element but I decided to use a 1:1 balun.
AA6DX wrote:
> The Mosely yagis often are(?)/were capacitive fed ... their "Classic"
> series. No hard wired connection to the driven element. That created an
> "unusual" situation, where the driven element is longer than the
reflector!
> Defeating a Classic system by connecting the coaxial cable directly to the
> driven would be a no-no, as would any other means of feeding, without
proper
> engineering. Note .. no all Mosely's are/were "Classic" .. I have had
> several that were, including my 2ØM monobander, w/46' boom ... worky
> worky... and, at one time, a Classic 36 .. Mark---- AA6DX
>
> Original Message -----
> From: "Alan C. Zack" <k7acz@cox.net>
> To: "Randy" <rlake@webryders.net>
> Cc: "J.Hector Garcia M" <Hector@telecom1.net>; <towertalk@contesting.com>;
> "Scott R." <w4pa@yahoo.com>
> Sent: Thursday, April 29, 2004 1:22 PM
> Subject: Re: [TowerTalk] Mystery Hy-Gain tribander
>
> > Scott said there was no matching devices on the yagi. You say the
SYS-36
> has a
> > hairpin matching device. I have a Mosley TA-33 that sounds very much
like
> what
> > Scott is describing. I'd suggest checking out:
> > http://www.mosley-electronics.com/amateur.htm
> > and seeing if what he has matches any of the Mosley yagis.
> >
> > Randy wrote:
> >
> > > My guess would be a Wilson SYS-33....try to find some pics on the
net..
> > > I have a SYS36 - 1 trap on the driven ele.but I have a hairpin on the
> boom
> > > attached to the DE.
> > > Good luck
> > > Randy N1KWF
> > >
> > > ----- Original Message -----
> > > From: "Alan C. Zack" <k7acz@cox.net>
> > > To: "J.Hector Garcia M" <Hector@telecom1.net>
> > > Cc: <towertalk@contesting.com>; "Scott R." <w4pa@yahoo.com>
> > > Sent: Thursday, April 29, 2004 2:21 AM
> > > Subject: Re: [TowerTalk] Mystery Hy-Gain tribander
> > >
> > > > I agree with J. Hector. A Mosley usually has one trap per element
> leg,
> > > where Cushcraft and Hy-Gain have two. And Mosley has a direct
> connection to
> > > the driven element, no matching devices,
> > > > but I usually use a balun.
> > > > 73
> > > >
> > > > "J.Hector Garcia M" wrote:
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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