Re: [TowerTalk] Hustler mobile resonators dipole

["Carl Smidt" <xveoneov@sprint.ca>]

Tom just lets his knowledge and long time experience shine through.

The Marconi 1/4 wave vertical, operating in conjunction with a ground 
system, was a classic in days of old. It was one of the first antenna 
designs that one learned about in early radio engineering classes.

I have taken the liberty to copy below what 'Google' has to say:

"The simplest vertical is the Marconi which is a quarter-wave radiator 
above a ground-plane. It has a feedpoint impedance over a perfect ground 
of 36 ohm. Above real ground it is usually between 50 and 75 ohm. This 
makes a good match for 50 ohm cable with the shield going to ground. For 
a given wavelength it is the smallest antenna with reasonable efficiency 
and so is a popular choice for mobile communication. It can be thought 
of as half of a dipole with the other half appearing as a virtual image 
in the ground".

73,   Carl   VE9OV

----- Original Message ----- 
From: "Pete Smith" <n4zr@contesting.com>
To: "Tom Rauch" <w8ji@contesting.com>; "Scott Fike" 
<kc0bus@hotmail.com>; <towertalk@contesting.com>
Sent: Monday, October 18, 2004 8:59 AM
Subject: Re: [TowerTalk] Hustler mobile resonators dipole


> Pretty funny -- I wasn't sure what Tom meant by a "Marconi", so I went 
> to the ARRL Antenna Book to look it up, and the only reference in the 
> index was to the guy who did those early experiments -- *that* 
> Marconi.  ON4UN's book had no index reference to Marconi at all.
>
> From context, I infer that Tom is talking about base-feeding one 
> mobile whip, as originally intended, and placing it over a good ground 
> plane.  Correct?  In that case, wouldn't another, more efficient 
> mobile antenna be a better choice?  I used a Hustler mobile whip in a 
> garden apartment back in the 70's, and while it worked, I never had 
> really good feelings about the resonator, since it got warm with only 
> 100 watts CW.
>
> 73, Pete N4ZR
>
>
>
> At 07:39 AM 10/18/2004, Tom Rauch wrote:
>
> > >   Specifically, I have been thinking of using two 80 meter
> > > Hustler/Newtronics mobile resonators fastened back to back
> > in a dipole
> > > configuration. Only instead of putting them in the more
> > common horizontal
> > > configuration, I was wanting to orient them in the
> > vertical position.
> >
> > Scott,
> >
> > My suggestion would be you do something different.
> >
> > You will have much poorer efficiency with a vertical dipole
> > of loaded elements compared to a similar height and coil
> > style antenna worked as a Marconi against a good ground
> > system.
> >
> >  If you can, you might consider as large a ground system as
> > you can muster (as many straight radials as you can fit, or
> > a screen) and a Marconi antenna. You will have less ground
> > loss, less feedline radiation, wider bandwidth, and better
> > antenna efficiency if you keep the same overall height and
> > use the antenna as a Marconi. The only thing you have to do
> > that is more work is install a ground of some type.
> >
> > A vertical dipole is workable, but decoupling the feedline
> > is a chore and the losses are pretty high with two mobile
> > antennas back-to-back.
> >
> > 73 Tom
> >
> >
> > _______________________________________________
> >
> > 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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> _______________________________________________
>
> 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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_______________________________________________

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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