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Old April 3rd 04, 12:49 AM
George Cronk
 
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Default Plans for a 5/8 wave 2M ground plane

Does anyone know where I can get plans for this antenna? Materials needed
to build one?

Thanks
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Old April 3rd 04, 01:36 AM
Cecil Moore
 
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George Cronk wrote:
Does anyone know where I can get plans for this antenna? Materials needed
to build one?


ARRL Antenna Book
--
73, Cecil, W5DXP



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Old April 3rd 04, 02:28 AM
David L Thompson
 
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MFJ makes a phased 5/8 wave 2 meter antenna that also works as a 1/2 wave
vertical on 6. Sells for $49 at HRO.
73 Dave K4JRB

George Cronk wrote in message
54.205...
Does anyone know where I can get plans for this antenna? Materials needed
to build one?

Thanks



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Old April 3rd 04, 06:27 AM
Mark Keith
 
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George Cronk wrote in message . 154.205...
Does anyone know where I can get plans for this antenna? Materials needed
to build one?

Thanks


You would be better off with a 1/4 wave ground plane on 2m. Seriously.
And one of those can be as simple as five 19 inch pieces of wire and a
So-239 connector. MK
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Old April 3rd 04, 12:36 PM
Dave VanHorn
 
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"Mark Keith" wrote in message
om...
George Cronk wrote in message

. 154.205...
Does anyone know where I can get plans for this antenna? Materials

needed
to build one?

Thanks


You would be better off with a 1/4 wave ground plane on 2m. Seriously.
And one of those can be as simple as five 19 inch pieces of wire and a
So-239 connector. MK


Why would he be better off with a 1/4 wave, with it's large vertical lobe?




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Old April 3rd 04, 04:53 PM
Richard Clark
 
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On Sat, 3 Apr 2004 06:36:31 -0500, "Dave VanHorn"
wrote:

You would be better off with a 1/4 wave ground plane on 2m. Seriously.
And one of those can be as simple as five 19 inch pieces of wire and a
So-239 connector. MK


Why would he be better off with a 1/4 wave, with it's large vertical lobe?


Hi Dave,

For any of a couple of reasons, principal among them being simplicity.
I have 2M, 220 and 440 versions with drooping radials that match quite
easily and couldn't be any cheaper for only the cost of the SO239. As
for "it's large vertical lobe," I am not sure what you mean by that.
The 5/8ths has more gain, but not so much more in a band and
application that is dominated by line of sight communication. If the
difference between the two is important to getting into a repeater,
getting into the repeater is not the same as full quieting and can be
an obnoxious advantage suffered by those who have to listen to a poor
connection. Such problems are more simply remedied by elevating the
existing antenna than trying to "add gain."

73's
Richard Clark, KB7QHC
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Old April 3rd 04, 08:35 PM
Dave VanHorn
 
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The 5/8ths has more gain, but not so much more in a band and
application that is dominated by line of sight communication.


Funny, it's made a significant difference for me in the decade or so I've
been using them.

A folded monopole is almost as simple, and has more gain as well.
http://www.w4dex.com/kc4fwc/proj_2.htm

If the
difference between the two is important to getting into a repeater,
getting into the repeater is not the same as full quieting and can be
an obnoxious advantage suffered by those who have to listen to a poor
connection.


?? More gain is worse?
I don't follow you. Being able to run into the same machines at lower power
is always good for my batteries, and taking me from noisy to quiet on the
same power is always a good thing.

Such problems are more simply remedied by elevating the
existing antenna than trying to "add gain."


Altitude is king, as long as you don't throw it all away in the feedline.


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Old April 3rd 04, 09:09 PM
Richard Clark
 
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On Sat, 3 Apr 2004 14:35:29 -0500, "Dave VanHorn"
wrote:


The 5/8ths has more gain, but not so much more in a band and
application that is dominated by line of sight communication.


Funny, it's made a significant difference for me in the decade or so I've
been using them.


Less than 1 dB is significant? Are we talking about VHF FM DXing?

If the
difference between the two is important to getting into a repeater,
getting into the repeater is not the same as full quieting and can be
an obnoxious advantage suffered by those who have to listen to a poor
connection.


?? More gain is worse?


More gain is not always enough gain. Again, if this is about getting
into a repeater, the less than 1dB difference that holds it open with
a scratchy signal is no panacea. There is nothing your contacts can
do to improve your poor S/N ratio; so, in a sense, it being better is
only from your point of view and an imposition on others to strain
their ears.

I don't follow you. Being able to run into the same machines at lower power
is always good for my batteries, and taking me from noisy to quiet on the
same power is always a good thing.


The same logic applies to getting your buddies to push your car to
boost your MPG. Better MPG cannot be said to be bad, but then you
aren't the one doing the pushing.

Such problems are more simply remedied by elevating the
existing antenna than trying to "add gain."


Altitude is king, as long as you don't throw it all away in the feedline.

Adding altitude also overcomes obstructions that could easily strip
away the added "loss" of the line.

My buddy's 2M repeater is over a nearby hill from me (I am roughly 100
feet below its crest) and 10 miles away. I can hit it with a pocket
HT (100mW with a cheesy antenna) from inside my basement, but move
into another room and it's a morgue. A "better" antenna is hardly
going to do as good a job as the same poor one above ground level. A
"better" antenna will not fit in the pocket, so "better" is entirely
subjective with its objective analysis not so much very better.

73's
Richard Clark, KB7QHC
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Old April 3rd 04, 09:36 PM
Cecil Moore
 
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Dave VanHorn wrote:
?? More gain is worse?


Depends on the TOA. Around Phoenix, we had a mountaintop repeater
that we could hit better with a 1/4 wave than with a 5/8 wave when
we were close to the base of the mountain upon which it resided.
That's where we camped out a lot.
--
73, Cecil, W5DXP



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Old April 4th 04, 12:40 AM
Dave VanHorn
 
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"Cecil Moore" wrote in message
...
Dave VanHorn wrote:
?? More gain is worse?


Depends on the TOA. Around Phoenix, we had a mountaintop repeater
that we could hit better with a 1/4 wave than with a 5/8 wave when
we were close to the base of the mountain upon which it resided.
That's where we camped out a lot.


I'm aware that there are off cases where the normal rules don't apply, but
in general, higher gain and a flatter pattern, is always better than lower
gain and heating the clouds..

I've not seen many hairpins out there, and they are just a small bit more to
build than the GP.
Why is that? Are they just not well known?



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