description of ppi target

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2026-05-17 09:18:28 -07:00
parent e280639211
commit 888a61baaf

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@@ -186,7 +186,7 @@ Individual scope informations
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The extent of the selection of the scopes by the user, there sill be
To control the extent of the selection of the scopes by the user, there sill be
a selection of what scopes are to be avaiable to the museum visitor. This
will enable the museum to select what scopes will be available and what scopes
will not be available at all. A script that will invoke the radar simulator
@@ -502,6 +502,28 @@ Individual scope informations
4. Long Term Amber - 10 seconds duration after Short Term; Amber hex #FFA040
5. Expiration - 12 seconds duration after Long Term Amber; very dark hex #050700
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Important Nuance For PPI Scope.
The radio frequency beam from the antenna has a finite width. It's not just a pencil thin
beam.
So what that means is the if there is any intersection between the target (whose dimentions
are passed to the shaders) and any part of the beam, including the very edges; you will get
an echo. The echo will be the weakest when the edge of the beam intersects with the edge of
the target that is closest to the beam. The strength is greatest when the axis of the radio
frequency beam is center to the center of the target as it appears in the direction of the
radar. This, of course, is affected by the heading of the target (the direction the target
is movine in relation to the position of the radar; if the target is heading to the radar, the
profile as see to the radar would be the smallest). Then as the radio frequency bearm moves
past the target, the intensity of the return signal would be weaker and weaker until the beam
completely passes the target and no more energy is returned.
So, the target would appear as a curved line that is perpendicular to the angle of the radio
frequency beam. The ends of the line would be the dimmest in intensity (weaker) and the center
of the target would be the brightest.
Graticules - These are plastic overlays over the face of the scope. They are
for the purposes of showing the bearing. They are calibrated in degrees; short line (1/8 inch)
each degree; medium line (1/4 inch) for every 5 degrees; and a longer line (1/2 inch) for every
@@ -509,6 +531,8 @@ Individual scope informations
Notes that these graticule lines are lit by a #47 incandescent bulb #FFB347.
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