Viavi C5TEM-R Rubidium Oscillator Timing Expansion Module (TEM)Condition: Used In good condition. Note only the module is supplied, you will need a compatible mainframe such as the MTS 5800 V2 From the manufacturer: Together with the T BERD MTS 5800 family, the field optimized TEM delivers industry leading accuracy to field portable timing and synchronization measurements. It features a GNSS antenna and a miniature atomic clock (MAC) to ensure nanosecond accurate measurements even when a satellite signal is not