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Old March 21st 06, 10:34 PM posted to rec.radio.amateur.antenna
David G. Nagel
 
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Default Dual rhombic antenna

Stargatesg1 wrote:
Also I would check to make sure the gain is listed as 26 DBd instead of DBi.
Back in the day, allot of companies inflated their specs by stating the
DBi gain instead of DBd.
DBi being gain over an isotropic and DBd being gain over a dipole.

At 26Db there isn't enough difference between dipole and isotropic to
matter.

Dave WD9BDZ
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Old March 21st 06, 10:50 PM posted to rec.radio.amateur.antenna
Roy Lewallen
 
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Default Dual rhombic antenna

To get 26 dB over a dipole would require rhombic leg lengths of about
125 wavelengths, or about 275 feet at 450 MHz. The overall length would
be around 500 feet. The beamwidth would be so narrow you'd have
difficulty getting it aimed toward one station, even if you were able to
turn it somehow.

Roy Lewallen, W7EL

David G. Nagel wrote:
Stargatesg1 wrote:
Also I would check to make sure the gain is listed as 26 DBd instead
of DBi.
Back in the day, allot of companies inflated their specs by
stating the
DBi gain instead of DBd.
DBi being gain over an isotropic and DBd being gain over a dipole.

At 26Db there isn't enough difference between dipole and isotropic to
matter.

Dave WD9BDZ

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