As you've found out, the PPI station has different power ranges for the radar "Range Selector" switch than the A-Scope. The below image shows the OTC three power ranges of the PPI as being 8,000 yards, 32,000 yards, and 80,000 yards. The function of the range selector switch gives the same result on each radar unit......a low, medium, and high power range distance.......although the actual readable ranges are different (its the way this game set up the radar
).
With the OTC PPI station, both range and target bearing can be quickly known when using the correct power range scale on the screen. The low (x000 yards), and high power range scales are displayed on the left side (the high power scale has an additional zero added; x0,000)....the medium power scale (32,000 yards, or x000) are displayed on the right scale.
If the power "Range Selector" switch were put on the PPI's 8,000 yard distance (which is the same as the 4,000 yard distance of the A-Scope....the low power setting) the below "blips" range would be found using the left hand "low" power scale (x000). The "blip" is at the 3,000 yard distance line, on a 10 degree relative bearing (use the leading edge of the sweep line to just contact the blip...follow the leading edge to the outer ring, relative bearing). Just like the previous post example of the A-Scope station, the target is found at the same range and bearing.
Once you understand the differences in range divisions for the two stations (yet learning the similarities of the power settings) you should be coming up with accurate radar information no matter which station you choose.