G.811 Reference Clock Source using the Digital Cesium technology


Telecommunication networks require highly accurate clocks for the effective transmission of digital signals. One of the primary objectives of telecommunication networks is to guarantee, at the connection between different networks, a slip rate of less than one slip in 72 days. Meeting these stringent specifications requires the implementation of a Primary Reference Clock (PRC) that must generate signals with an accuracy greater than 1E-11, at all times. Generally, this is achieved using Cesium clock technology, often combined with GPS receivers as backup sources. Unlike off-air receivers, Cesium clocks are autonomous, self-contained primary references immune from external influences.

The Oscilloquartz’s OSA 3230B Cesium Clock is specifically designed and produced with the latest technology to serve complex applications where an extremely accurate reference signal is needed in a minimum size.



  • Performance exceeding ITU-T G.811/Stratum 1 PRC
  • Accuracy better than ±1×10-12 during entire life
  • Long life 10 years cesium tube
  • Extremely compact size
  • 10MHz and 5MHz low noise outputs
  • 100kHz to 50MHz programmable sine wave analog output
  • 3xoutputs configurable between 1pps/1MHz/5MHz/10MHz-TTL level
  • 1PPS external synchronization input
  • Optional Signal Expansion, providing 5 additional outputs
  • Redundant DC power supply inputs or mixed AC+DC power supply
  • Control and monitoring via alarm contacts and RS 232 communication
  • TCP/IP Remote management port for TL1 and/or SNMP management