Electronic Design

System Provides Precise Frequency, Time For T&M

The XLi time and frequency system functions as a very high-precision time and frequency source for test and measurement applications. As a GPS timing receiver, the XLi can track up to 12 GPS satellites, providing 1 × 1012 frequency output accuracy. Using the long-term stability of the GPS systems to steer the receiver's local oscillator, it supplies better than 30-ns accuracy compared to Coordinated Universal Time and the U.S. Naval Observatory.

The rack-mountable XLi can also act as a time code unit. It can combine up to 10 plug-in option boards as well as oscillator upgrades. Two power supplies can be combined for versatility. With available options, the unit provides an array of outputs: 1PPS (1, 5, 10 MPPS), IRIG-B (A, E, G, H, Xr3/2137, and NASA 36), serial I/O, T1, E1, and low phase-noise (5, 10 MHz). Every XLi option can be configured for redundancy to ensure performance in contingency situations.

For telecom networks, the XLi can accommodate a plug-in card that provides timing signals meeting ITU-T G.703/G.704 requirements. For synchronizing servers and workstations across the network, accurate time is generated by the host XLi and distributed over the network using the Network Time Protocol (NTP). To achieve this, the XLi has a network-centric interface that supports Telnet, DHCP, NTP, and SNMP.

This system includes a brilliant fluorescent display and a 16-key keypad. Available options include a low-phase-noise card and an upgraded clock oscillator. Shipping now, the basic XLi system costs $3300.

TrueTime Inc., www.truetime.com; (800) 328-1230.

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