Pendulum CNT-91
The CNT-91 Timer/Counter/Analyzer is the highest performance counter for measurement, analysis and calibration of frequency, time interval and phase. The CNT-91 is very suitable for production test systems, for R&D, in calibration labs, or in the field.
The CNT-91R is basically a combination of the high resolution CNT-91 and a Rubidium Frequency Standard, all in one box. 
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