NavCom RT-3020 Rev.D - Manual (Page 25)

RT-3020 User Guide - Rev. E
There should be an unobstructed view of the sky above
a 10-degree
elevation mask for optimum GPS satellite
visibility for RTK use. Any obstructions above the
horizon should be mapped using a compass and
clinometer and used in satellite prediction software with
a recent satellite
almanac to assess the impact on
satellite visibility at that location. Potential sources of
interference should also be avoided where possible.
Examples of interference sources include overhead
power lines, radio transmitters and nearby electrical
equipment.
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