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Bruce in Alaska
 
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In article ,
Jeff Morris wrote:

I'm still not sure of the value for long distance viewing, but the high
power dome will have finer resolution, so that a pair of channel buoys
will be resolved as two targets further away with the more powerful
unit. Navigation is easier, since coastlines will more closely resemble
the chart. However, this takes a lot of practice and you're better off
relying on a good gps.



The above is due to a narrower Horizontal Beamwidth, and not the PPP
(Peak Pukse Power) of the transmitter. Radar OEM's tend to put the
bigger antennas (narrower Horizontal Beamwidth) on their Larger PPP
transmitters as a rule, but the two are mutually exclusive
specifications. Third and fourth Generation Marine Radars, all have
Log Recivers, SolidState Frontends, and that is why they preform
as well as the older Second Generation Radars that had twice the PPP
in the transmitters. Where it used to take 10Kw and a 6 Ft SlotLine
antenna to pickup 48 mile targets in second genertion Marine Radars,
the 4Kw 4Ft Slotline antennas of the Fourth Generation work just fine
on the same paths. Like wise the 2Kw 3Ft Slotline Radars of the Third
Generation will compare very nicely with a 2Kw flatpanel antennas of
todays small boat radars, with the exception of the very wide Horozontal
Beamwidths of those flat panel antennas, that can't differentiate between
two targets at the same distance, but closer than 6 or 7 degrees in
bearing.


Bruce in alaska
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