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KC2UGV
08-20-2010, 11:05 AM
Question, If I have two dipoles, one N-S, and the other E-W, and have them fed out of phase 180*, will I get essentially an omni-vertical antenna (As far as signal strength pattern)?

Would there be any benefit to this?

Also, what does the signal pattern look like on a vertical dipole? Same as a horizontal dipole?

I know the first thing is: Model it! I suck hard at eznec. Can never get the wires to line up right.

WØTKX
08-20-2010, 01:12 PM
How aboooooot a "maypole" antenna... http://www.qso.com/westsat/Maypole/index.html

W5GA
08-20-2010, 05:10 PM
Question, If I have two dipoles, one N-S, and the other E-W, and have them fed out of phase 180*, will I get essentially an omni-vertical antenna (As far as signal strength pattern)?

Would there be any benefit to this?

Also, what does the signal pattern look like on a vertical dipole? Same as a horizontal dipole?

I know the first thing is: Model it! I suck hard at eznec. Can never get the wires to line up right.
What freq? The patterns I see in EZNEC aren't even close. If you talking 40, 80 or 160 it's really moot, as the majority of radiation is up (not so much on 40) unless you have LOTS of tower to play with. The null off the ends a dipole aren't really that great if it's low.
The ARRL Antenna Book comes with basic version of EZNEC with a ton of canned examples you can look at, although in my version they're for 80m. EZNEC will rescale them automatically for you though if you tell it what freq you want.

KC2UGV
08-20-2010, 07:31 PM
What freq? The patterns I see in EZNEC aren't even close. If you talking 40, 80 or 160 it's really moot, as the majority of radiation is up (not so much on 40) unless you have LOTS of tower to play with. The null off the ends a dipole aren't really that great if it's low.
The ARRL Antenna Book comes with basic version of EZNEC with a ton of canned examples you can look at, although in my version they're for 80m. EZNEC will rescale them automatically for you though if you tell it what freq you want.

Ok, well stupid favor to ask: Can you send me your models (Just the two, a phased dipole and a vertical)?

W5GA
08-20-2010, 08:28 PM
Be happy to. Shoot me your email.

N8YX
08-22-2010, 07:16 AM
If you feed a pair of crossed dipoles 90 degrees out of phase you'll get an omni pattern.

See here:

http://en.wikipedia.org/wiki/Turnstile_antenna