MTS/TBERD 5800 V2 TEM number of satellites

How many satellites does the MTS/TBERD 5800 V2 Timing Expansion Module (TEM) need to see in order to operate properly?

For completing a proper survey, the MTS/TBERD V2 TEM needs to have good signal from 4 satellites. Once the survey has completed and the TEM is in the Fixed Position mode, only one satellite signal is required to maintain timing and time Of Day (TOD) sync.