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Re: Egg Beater Antennas and AO-40




>From: "Robert M. Beatty" <rmbeatty@home.com>
>I've noted a few posts to the mail list requesting info on the "Egg
>Beater" type
>antenna, so I thought I would share my limited experience...
>
>I've been using a M2 EB144 (Egg Beater) antenna to pickup the 2mtr
>telemetry
>from AO-40.  The antenna is six feet off the ground, and fed with 50
>feet of
>RG8X.  With my Kenwood TS-790A, I get S meter readings of S1 to S3
>without the
>need to worry about tracking.
>
>Over the next few days I will be adding the radial kit (it was
>backordered), and
>will have an SSB SP-2000 mast mount pre-amp installed, along with some
>low loss
>9913 cable.  I'll report back what the S meter readings are when that is
>
>completed.
>
>By the way, I have been using the Egg Beater for regional repeater use
>with good
>results even though it is horizontally polarized at the horizon.  (I
>seem to
>remember that you loose about 6dB for polarization mis-match.)

Bob,

Polarization mismatch for V to H is ~20 dB.  Probably the eggbeater is not
pure Horz since it is using loops.  The eggbeater is circular pol straight up.

Here is the prediction from "P3D to P3G" for dipoles over ground plane
[basically what an eggbeater is-gainwise]:

VHF downlink:  a 15 dB SNR
UHF uplink:  using 50w will produce 23 dB SNR at P3D

Actual performance is to be determined, of course!

I believe the eggbeaters cost around $200/each.  Two arrow beams would cost
half that and you could mount them on a wood "broomstick" cross beam
withone H other V and feed 90 deg out of phase for circular pol {alt mount
them / and \}.  This should net you around 5 dB better signal up and down!

my two cents ;-)

Ed
Using four 20 element H/V 2m yagis {19 dBi} and one M2-436CP42 on
70cm...just to brag ;-)  Course I got 5 acres in the country!   
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