Polar regions are covered with the Universal Polar Stereographic grid system. For positions in the Southern Hemisphere, the Equator has a northing coordinate of 10,000km north. Washington, D.C., at 77 W, is in Zone 18. There are 108 from the IDL to the eastern boundary of Zone 18. For positions west of Greenwich, add 6 to obtain the western boundary.
Measure distances to the feature from the closest grid lines to the west and south of it.
The radio tower is 0.08in east of the tic mark. The radio tower is 0.22in north of the tic mark. So, the tower's northing is 4,469,135m 4. State Plane Coordinate system - Application of rectangular coordinate system to each US state for survey purposes. The number of zones is determined by pre-established distortion limits based on chosen projection.