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Old January 16th 07, 05:26 PM posted to rec.radio.amateur.antenna
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Default do I have my antenna fundamentals right?

On Tue, 16 Jan 2007 09:16:30 -0500, Bud wrote:

Not sure where you are, check to see if there are any
nets on the repeaters in the area


Near Fort Worth.

73's
Richard Clark, KB7QHC
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Old January 16th 07, 06:12 PM posted to rec.radio.amateur.antenna
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Default do I have my antenna fundamentals right?

MK, this diagram is fantastic! I guess I should have explained to all
of you that as a college student I have more time than money, so it may
be a while before I can even afford the PVC and wire. I bet it will
outperform my mobile-dipole-on-a-stick, though!

Nelson

On Jan 16, 10:22 am, wrote:
markus wrote:
hi Nelson,


yes, it is a lot of work, you could just attach the magmount
to any metal object, patio table, metal railing or window a/c unit, etc.Yea, I suppose you could... Arf.... :/




or for a few dollars and less work build a great 2m antenna
using #12 thhn wire and a few feet of pvc pipe.With even less work and $$$, he could just build a ground plane

using 5 wires and a so-239 or whatever..



this is the half square, works great, it is directional.Probably not what he wants for 2 meters, unless he can steer

the pattern.



http://cebik.com/vhf/hs.html


then you can try this one, the Moxon for 2m, little harder to make
but has similar gain to a 2 element yagi in less space and direct fed
with 50 ohm coax (like the half square is fed).Antennas are small on 2m.. He could live a little and use 3 elements

and have a good bit more gain. But then he has to rotate the thing..
I recommend a easy 1/4 wave ground plane to start. It will work about
as well or better as any of the other "easy" vertical whips for 2
meters.
Attaching a 2 meter whip to a railing, table, AC unit , etc is going to
function in a fairly poor manner. The ground radials need to be
resonant to function properly. Would be much better to use 4 simple
quarter wave radials. You can slope them down at about 45 degrees
to get a better match, and maybe a tiny bit more gain.
MK


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Old January 16th 07, 07:42 PM posted to rec.radio.amateur.antenna
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Default do I have my antenna fundamentals right?

Richard Clark wrote:
On Tue, 16 Jan 2007 09:16:30 -0500, Bud wrote:

Not sure where you are, check to see if there are any
nets on the repeaters in the area


Near Fort Worth.

73's
Richard Clark, KB7QHC


Richard;

Go to the following URL: http://www.artscipub.com/repeaters/

click on Texas and search for "Fort Worth". You should get two pages of
both VHF and UHF repeaters.

Dave WD9BDZ
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Old January 17th 07, 04:39 AM posted to rec.radio.amateur.antenna
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Default do I have my antenna fundamentals right?


Nelson Blaha wrote:
MK, this diagram is fantastic! I guess I should have explained to all
of you that as a college student I have more time than money, so it may
be a while before I can even afford the PVC and wire. I bet it will
outperform my mobile-dipole-on-a-stick, though!



Someone else posted that.. Myself, I wouldn't use one of those on 2m.
Sure, it would work, but for about the same or less amount of work
you could have a small 3 el yagi.
I would not use a directional antenna unless you had an easy way to
turn it.
A ground plane is super cheap, and will do just fine. You can place
them
on a mast, hang them from ceilings, etc. I've got a ground plane hung
in my
attic for emergency use. With 2m FM, gain is not really that important.
Decoupling from the feedline is though. The decoupling with the GP will
be fairly decent. If you use an off size "counterpoise" to mount a whip
on,
it's not resonant, and generally will do a poor job vs a complete
antenna.
You will find in most cases like that, the decoupling from the feedline
will be
poor too.
I'd start with a simple 1/4 wave ground plane, and go from there.
All you need is a SO-239 and 5 pieces of wire about 19-20 inches long.
Most bend the lower ground radials down at about 45 degrees to
get a better match to 50 ohms. You can set one on a table unless
the coax is thick... :/
Can't get much cheaper than that, and it will work well. To me, the
half square is too much work, too little gain for 2m.. Good for HF
tho..
A 3 el yagi would clobber that thing on 2m, and isn't too much bigger..
MK

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Old January 17th 07, 05:55 AM posted to rec.radio.amateur.antenna
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Default do I have my antenna fundamentals right?


"Nelson Blaha" wrote in message
ps.com...
Having gotten some help around here on how to power my 2m mobile
indoors cheaply, I need to figure out a way to get an antenna. There
are probably a million holes in this plan, please point them
all out to me!

I intend to get a piece of square sheet metal (ground plane?) about
half a meter each way, and build a bracket to hold it outside my window
horizontally. In the center of the sheet metal I'll install an NMO
mount for my mobile antenna. I'm actually planning to ground the sheet
metal using the electrical ground in the wall socket (surely
something's wrong with THAT!) I look forward to better alternatives!


IF I were working off a balcony I would use a Yagi or maybe a quad sense the
building will be blocking the signal in at one direction any way. I used to
hace a two element quad I made on a broom. I would sit on the balcony and
hold the quad in one hand and my HT in the other. BAd thing is that now
there is now way to hold the beer.




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Old January 21st 07, 10:19 PM posted to rec.radio.amateur.antenna
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Default do I have my antenna fundamentals right?

You could go to your local Radio Shack and look for a scanner antenna. They
have a small vertical with 3 eleament ground radials.
I bought one for $11 in the bargin bin for a new ham in my area..
You can even use it to transmit on 2meter band (after your legal)

Joe KI4ILB

I intend to get a piece of square sheet metal (ground plane?) about
half a meter each way, and build a bracket to hold it outside my window
horizontally. In the center of the sheet metal I'll install an NMO
mount for my mobile antenna. I'm actually planning to ground the sheet
metal using the electrical ground in the wall socket (surely
something's wrong with THAT!) I look forward to better alternatives!


IF I were working off a balcony I would use a Yagi or maybe a quad sense

the
building will be blocking the signal in at one direction any way. I used

to
hace a two element quad I made on a broom. I would sit on the balcony and
hold the quad in one hand and my HT in the other. BAd thing is that now
there is now way to hold the beer.




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