Spectra Precision FAST Survey Reference Manual - Manual (Page 356)

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Choosing Edit will bring you to the screen below:
From this screen, you can select the Projection calculation method as well as calculation parameters. Projections
include:
Lambert Conformal_Conic_2SP,
Transverse_Mercator,
Oblique_Sterographic (Double),
Lambert_Conformal_Conic_1SP,
Oblique_Mercator_83,
Stereographic, Oblique_Mercator_27,
Transverse_Mercator_OSTN02,
Oblique_Stereographic_RD2000,
Oblique_Mercator,
Cassini_Soldner,
Transverse_Mercator_27,
Lambert_Conformal_Conic_27,
Transverse_Mercator_Alaska_27
Transverse_Mercator_34.
You may also use the buttons on this screen to edit the existing datum or create a new datum definition.