Paul,
I'm not quite sure what point you are making.
The dipole doesn't just "cut off" below some angle. Let's suppose the
vertical had a 10db advantage over the dipole at 6 degrees, and the
dipole beat the vertical by 10dB at 23 degrees. If your point is that
the signal strength on the 6 degrees path is very much stronger (say by
20dB) than that on the 23 degree path, the vertical will still only show
a 10dB advantage because the 6 degree path is dominant for both antennas.
Or have I misunderstood what you are saying?
Steve G3TXQ
Paul Playford wrote:
> Just for yucks, bring up W6ELprop and:
>
> insert 23 degrees as your Minimum Radiation Angle (Options - Prediction
> Parameters).
> Then run a prediction to a country maybe 10000 Km away.
> Look at the predicted signal levels and scroll to the time that the best
> signal level will occur on your chosen band.
> Click on Advanced and scroll to the same time and note the Hop
> Configuration.
>
> Now insert 1.5 degrees as your Minimum Radiation Angle
> run the prediction again
> scroll to the same time
> observe the Hop Configuration
>
> And take a guess at how much signal you lose for each additional hop the 23
> degree path takes as compared to the 6 degree path. That will give you an
> idea of the differences you are observing and cannot be inserted into EZNEC.
>
> de Paul, W8AEF
>
> ZF2JI/ZF2TA FO8DX/FO8PLA 8Q7AA XZ0A VU7RG TX5C
>
>
>
> ----- Original Message -----
> From: "Steve Hunt" <steve@karinya.net>
> To: <towertalk@contesting.com>
> Sent: Sunday, April 05, 2009 1:02 PM
> Subject: Re: [TowerTalk] EZNEC- needs improvement
>
>
>
>> Dick,
>>
>> It seems to me that EZNEC would confirm your own experience. If I model
>> a 40m dipole at 90ft over salt water compared to a 1/4 wave vertical at
>> ground level, EZNEC has the vertical better at low angles, by as much as
>> 10dB. I realise the XM-240 should do better than the dipole I modelled,
>> but not by more that 3 or 4 dB I would have thought.
>>
>> Steve G3TXQ
>>
>>
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