Siemens NFR2001¶

Overview¶

The Siemens Normalfrequenzeinrichtung NFR2001 is a clock processing, selection and distribution unit for PDH and SDH networks. It receives one or multiple reference signals [traditionally from atomic clocks], processes the signals to compensate for transmission errors and synchronizes a two-stage PLL to remove high frequency jitter and wander.

The NFR2001 generates a local clock referecne which can be provided to PDH and SDH transmission equpment.

In case the active reference signal fails, the NFR2001 provides fail-over from its internal reference until the firmware has switched over to a new reference signal.

NFR2001 is internally redundant; all components/modules exist twice and can fail-over whenever needed. This also allows servicing or upgrade/downgrade while remaining fully operational.

The NFR2001 allows for the following clock inputs:

• 2.048 Mbit/s data signal
• 2.048 MHz clock signal
• 10 MHz clock signal

The NFR2001 provides the following clock outputs:

• [up to 60] 2.048 MHz clock reference outputs (G.703) 75 ohms unbalanced or 120 ohms balanced.

Hardware¶

Manuals (German)¶

• NFR2001 Information.pdf
• NFR2001 Bedienung.pdf