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Old December 22nd 04, 11:52 PM
W4JLE
 
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Let me suggest that you order a copy of the ARRL Amateur Radio Handbook.
Just like any other hobby, this one has a bible that answers most of the
questions that come to mind. You can save yourself the delay of having to
ask and wait for a reply.

To answer your questions.
A J-pole requires a balun to eliminate feed line radiation.

The difference between it and a yagi at the same height can be likened to a
yard sprinkler vs. a hose nozzle. Same amount of water comes out the hose,
the j-pole sprays the signal all around, the yagi is the hose nozzle. Are
you trying to get a crowd wet, or a single person?

On VHF your more often limited by line of sight distance than signal
strength. If your beyond line of sight, a gazillion watts or a 100 element
beam won't help.

The red things keep you from poking your eyes out.

wrote in message
oups.com...

W4JLE wrote:
For two meters and 440 I would suggest a J-pole. If you look on the

arrow
antenna site http://www.arrowantennas.com/j-pole.html
He gives you the information to build your own. FM by mutual

agreement is
vertical where sideband is horizontal. This relationship is used on

VHF and
UHF.

On 6 meters a simple dipole will get you started. Use the formula
468/desired frequency in MHz equals the total wire length in feet.

Make it a
little longer for adjustment purposes then cut it in half. Add a

center
insulator and end insulators. At low power (=100 watts) use pieces

of PVC
pipe. Tie the shield of the coax to one side of center and the center
conductor to the other.

Welcome to amateur radio and if I can help you in any way just e-mail

me.

73 Fred

wrote in message
ups.com...
New to ham radio. Interested in building an antenna for a base

station.
I dont have anything yet, just in the planning stage.


Thought about buying a handheld and using that as part of my "base
station" one maybe capable of 2 440 and 6. These seem cheaper used

than
the home units.


My question is, is there information out there on how to build one?

I
have a radio shack book at home that has a plan for a 440. It uses
aluminum ground wire. What I find when working with this stuff is

it is
impossible to make it perfectlyu straight. Doesn't that effect the
performance? I mean it comes coiled and when I cut it to length I

cant
get it perfectly straight.


Also, it is posisble to have good performance with one antenna for

all
the bands? Or is it absolutely necessary to have one antenna for

each
band? I have limited room.


I appreciate your help!


I like the looks of that. I wonder if I could use stainless? Is it
necessary to use a balun on that?

At the same height, what would the difference be between this one and a
6 element yagi?

What are those red things on the top? They look like wire twisters.