
Page 36
F
IGURE
15-1
D
AISY
-
CHAINING THE TIME SYNCHRONISATION CONNECTIONS
“T” indicates a 50Ω SMA termination.
The total length of cable used in the daisy-chain must not exceed 50m (165 feet).
15.1
Setting the Synchronisation Source
Each EtherSpaceLink unit waits to synchronise with a time reference unit and the chain must include ONE
reference unit which provides the time for all of the others. Any EtherSpaceLink unit may be used as the time
reference and must be set as such by using the switch on the front panel.
Pushing the front panel switch up and down (or down and up) followed by up produces a synchronisation status
screen (See section 6.1, “IP address”). Settings that can then be selected by pushing the switch down are:
Synchronise to an external time reference, when available (default);
Isolated - times are local, even if a reference is available;
Act as a time reference for other EtherSpaceLink units.
When several EtherSpaceLink units are synchronised together, one of them must be set to be the time reference,
and all of the others may be left at their default setting to cause them to synchronise their timetags to that unit.