The Symmetricom Time Source 2700 primary frequency standard produces a very high precision 10 MHz signal that can be used to calibrate frequency dependent devices like frequency counters, spectrum analyzers and such. These same devises typically have a 10 MHz External reference input that can be driven with the Symmetricom giving the piece of equipment the ability to make very high precision measurements. Most equipment also has a 10 MHz output that allows multiple devises to share one Frequency standard.
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