The CNT-91 from Pendulum Instruments is a frequency counter/timer/analyzer that compliments the CNT-90 with higher speed, greater resolution, and added features. The frequency range for the unit extends to 20 GHz. Added features include continuous data "streaming" and the ability to program a pulse output from 0.5 Hz to 50 MHz for defining pulse-rate frequency.

Other features include a measurement speed of up to 2600 individual measurement results per second via a GPIB/USB interface; 50 ps single-shot (time) or 12 digits per second (frequency) resolution; modulation domain analysis; and zero-dead-time counting to provide period back-to-back measurements and the correct input for Allan Deviation calculation. This counter also has true graphic capabilities on-screen for expanded statistical processing.