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Date: Sat, 18 Feb 2006 20:40:05 -0500
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From: "Bob Jude" <bobjude@charter.net>
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Subject: Re: [LML] Re: My solution to Comm Antenna ground plane-ACTUAL TESTING
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Tim, This is just a little something to add to your ground plane study.
VSWR is an important test parameter for antenna performance but it is not
the only thing to consider.
A ground plane that is not a good conductor can dissipate RF energy and
still show a good VSWR.
A complete test of antenna performance should include field strength and
antenna radiation pattern measurements.
Bob Jude
N65BJ
P.S. I used to do that stuff for a living.

----- Original Message ----- 
From: "Timothy Ong" <timothy.ong@leadingedgeaircraft.com>
Sent: Saturday, February 18, 2006 12:51 AM
Subject: Re: [LML] Re: My solution to Comm Antenna ground plane-ACTUAL
TESTING


> Just some other data points as we have done quite a bit of testing in the
> last year on ground planes.
>
> Conductive paint ground plane with external com antenna  VSWR 1.15:1-1.3:1
> at mid freq.
>
> Copper mesh or aluminum tape ground plane on inside
> VSWR 1.7:1-2.0:1 at mid freq.
>
> No ground plane only using carbon
> VSWR 1:8:1-2.4:1 at mid freq.
>
> These were actual tests conducted on multiple airframes using a digital
VSWR
> meter.
>
> This is for com.  We have had excellent results with com, nav,
transponder,
> and TCAD antennas using the conductive paint.  I have heard that the paint
> can breakdown overtime.  I'm not sure how this can happen under a coat of
> WLS primer, but I'm sure someone will educate me :)  So far we have a
couple
> of airplanes now that are 2+ years old with no appreciable degradation.
>
> Regards,
>
> Timothy Ong
>
>
>