R&S M3SR 4100 Series, Operating Manual

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M3SR Series 4100 Basics of ALE-2G LP
4.8 Operating Manual 6175.4760.02 – 01
Installing a net station:
1. Enter the linking protection key.
2. Set the configuration parameters for example as follows:
- Link protection level: 1 or 2
- Fine time request: ON
- Coarse time request: ON
- Unprotected time request: ON
- Passive time acquisition: ON
- Time request interval: 5 min
- Time server: OFF
3. Enter the ALE net time with a precision of ±10 s or better.
After the time request interval has elapsed the net station sends a time request to the server.
The station can be switched off, although in this case the time quality quickly deteri-
orates.
4.3.2.2 Maintaining Network Synchronism
Due to the inaccuracy of the internal clock, synchronism of the net stations will be lost in the
course of time. The table below shows how long a net station on protection level 1 or 2 is
able to keep itself synchronized.
Table 4.3 Time to Keep Radio (Net Station) Synchronized
The table assumes that the time server is not switched off.
When the time quality of a station falls below a certain threshold, the time acquisition protocol
is started automatically. Using this protocol the station tries to improve its time quality. The
intervals between these attempts can be programmed with the parameter time request inter-
val. The protocol runs until the time quality reaches a sufficient value.
Protection level Radio switched on or off all the time
Radio switched on Radio switched off
AL-1 approx. 2 years approx. 3 months
AL-2 23 days 2.5 days