[50mhz] polarization ?
Chris Boone
cboone at earthlink.net
Mon Oct 17 13:41:55 EDT 2011
INCORRECT....A loop by itself has NO GAIN..it is a dipole bent into a omni
directional (well not totally) shape..actually all loops have a null except
the PAR...it is closest to being OMNI to any HORIZONTAL antenna...all others
have a slight NULL in the direction of the open end of the loop looking from
the feedpoint.
You cannot get gain from a dipole!!! (hence the reference dbd....gain
referenced to a DIPOLE...dbi is referenced to a NON existant antenna....a
Isotropic that radiates in all directions equally..it does NOT exist..only
in theory!)
ANY gain claimed by loops is due to normal ground reflections that MAY add
slightly (1db at the most) IF properly phased (MOST are not...and thus
actually reduces the signal) but it is not true GAIN...HOWEVER, any loop
mounted 10ft or higher above ground (which is where they need to be!!) has
NO ground reflections and thus is no better than a dipole broadside to the
receive station (since a dipole has a figure 8 pattern 90degrees to the
dipole itself).
Smoke and mirrors cannot change the laws of physics...
Stacking TWO loops WILL Get you 3db gain....that is true of ANY antenna of
the same design properly stacked horizontal or vertical...
Anything more than that is a lie......it CANNOT happen.....
(I can go drag my EE books out from my college days if you like ;)
Chris
WB5ITT
-----Original Message-----
From: 50mhz-bounces at mailman.qth.net [mailto:50mhz-bounces at mailman.qth.net]
On Behalf Of Ed Zeranski
Sent: Monday, October 17, 2011 8:02 AM
To: W0MU Mike Fatchett; 50mhz at mailman.qth.net
Subject: Re: [50mhz] polarization ?
How about a loop? The M2 6m loop has gain in all directions. I would
mount a loop horizontally.
Mike W0MU
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