Section 3: Operation
NetClock/GTP Instruction Manual
Page 3-29
The Model 8185, TimeBurst
, provides a digital time-of-day data burst to a radio
transmitter. The TimeBurst, when used with the Spectracom Model 8186
TimeBridge
, provides community-wide time synchronization from a single
NetClock/GTP. The TimeBurst accepts only Format 0. Connect the TimeBurst
to the RS-485 data bus using a 3-position terminal block as shown in Figure 3-
15.
FIGURE 3-15 TIMEBURST RS-485 INTERFACE
3.4.3 Termination
A termination resistor is required on devices located at the ends of the RS-485
transmission line. Terminating the cable end preserves data integrity by
preventing signal reflections.
For a one-way bus installation (shown in Figure 3-8), terminate the last device on
the bus. The RS-485 data bus can be split in two directions as shown in
Figure 3-9. In a split bus configuration, terminate the devices installed on each
end of the bus. Most Spectracom products include a built in termination switch to
terminate the RS-485 bus when required.
