Making my own Circularly Polarized Antenna

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BriansBrain
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Making my own Circularly Polarized Antenna

Post by BriansBrain »

Hello all you antenna freaks :lol:

The location of my antenna is like this.

My potential listeners in %
To the front 75%
To the rear 22%
To the right 3% (but very close less than 100m, after that its mountains only)
To the left 0% (the sea)

So I am making my own atenna to cover the area :wink:
After many design hours I have come up with one :roll:
And this is what it will look like :P

. . . . . . . > Image


*NOTE*
All measurements are with a 2m long mounting pole connected to the boom (as pic).

The polar diagram

. . . . . . . > Image

The SWR at my chosen frequency comes out at 1.52649
The impedance at my chosen frequency comes out at 196.479
All I need will be a 4:1 balun using RG-213 like this

. . . . . . . > Image

Unless I come up with a better one that is (I'm never satisfied) :o


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BriansBrain
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Post by BriansBrain »

The Horizontal Plane at my 98.6MHz

. . . . . . . . . > Image

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pcs
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Post by pcs »

Interesting indeed :)
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
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BriansBrain
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Post by BriansBrain »

pcs wrote:Interesting indeed :)
It cetainly is :lol:

But it's a pig to design, the position of the mast in original
design is causing SWR problems, it's very critical :(

So..... Back to the drawing board :roll:

Many hours later I have come up with this beauty :P

Design. . . . . . . > Image

All measurements taken as picture (with a beam, fitted to a mast)
Using the 4nec2 Program

Rear Gain 2.29dbi
Front Gain 6.05dbi
SWR 1.02579
Imp 195.791 Ohm


Gain. . . . . . . > Image

SWR. . . . . . . > Image

Imp. . . . . . . > Image

Hor. . . . . . . > Image

Ver. . . . . . . > Image

And the best thing is the girlfriend likes it, she says it looks sexy :oops:


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BriansBrain
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Post by BriansBrain »

For some reason only small pics came out this time :cry:

Anyone interested here are the full size Pics :D

Design. . . . . . . > http://postimg.org/image/d45rb3p53/

Gain. . . . . . . > http://postimg.org/image/xyszlkte7/

SWR. . . . . . . > http://postimg.org/image/7t99krvch/

Imp. . . . . . . > http://postimg.org/image/3w9fbg8cz/

Hor. . . . . . . > http://postimg.org/image/kvm0e5ylj/

Ver. . . . . . . > http://postimg.org/image/6peekxwar/


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