When locked to Global Positioning System (GPS), the 58503 GPS time and frequency reference receiver from Symmetricom (San Jose, CA) generates a 10-MHz reference sine-wave signal with accuracy of better than 1 x 10-12 for a one-day average. The generator also provides a 1 pulse-per-second (PPS) signal with less than 750-ps root-mean-square (RMS) timing jitter. Even when the GPS signal is lost, the receiver enters an intelligent holdover mode in which frequency accuracy is maintained to better than 1 x 10-10 per day using the company's proprietary SmartClock technology. Although based on a quartz-crystal oscillator, the SmartClock technology enables the 58503 receiver to approach the performance of a more expensive rubidium-based time-and-frequency standard. The receiver is ideal for any measurement application requiring a precise external reference source for improved stability and enhanced synchronization capability.

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