Mike Dennison wrote:
> G3KEV- IO94SH ---------G3WSC/P- IO91XS--------AZ 175, DISTANCE 287.3 Kms
>
> G3KEV- IO94SH -------- MM0ALM- IO87UA--------AZ 340, DISTANCE 320.8 Kms
>
> MM0ALM is 2db stronger
> de G3KEV/SCARBOROUGH.
So, if both MM0ALM and G3WSC were running 1W ERP, this
completely destroys the argument that higher antennas
always work better for the same ERP!
Mike.
Speculation again. Do you know exactly the paramaters of each site, and power
levels.
One site has one tower at over 300 ft and the other, two towers at 130 ft but
possible a more elaborate antenna system.
I gave the signal levels as received at my QTH but do not have any other
details except that it has been suggested in a previous message that G3WSC was
running more like 2 w erp.
Earth losses, radial systems need some consideration also, in this case the
the higher tower might not be optimised.
The performance of a 300 ft tower on one site might be totally different for
the same tower on another site, because of local environment, coastal or
inland, humidity etc. This has all been discussed before and never been been
satisfactory resolved.
A short tower on a very good site would possibly outperform a larger tower on
a poor site.
I do not really get your point since neither of us know the facts.
I did notice tonight that the decca signal was stronger than the earlier test.
I expect the power has been increased but only about 5 db difference. I think
they are reaching the diminishing returns situation where the power would need
to be increased significantly to be really noticeable.
Their signal in no way matches DFC considering how close they are to me.
When I get time I must make some measurements on the analyser for comparison
purposes.
73 G3KEV
Mike, G3XDV (IO91VT)
http://www.dennison.demon.co.uk/activity.htm
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