Time Interval Counter

Product Benefits:

  • Compare to the best counters on the market
  • Superior capability at a remarkably low price
  • Exceptional resolution in time and frequency
  • 100 pS (0.1 nS) without averaging
  • 10 digits/S in frequency (7 digits in 1 mS)
  • Matched 100 MHz input channels
  • Complete instrument-on-a-card


The GT200-10 Time Interval Counters are currently in use in thousands of applications ranging from satellite tracking to monitoring of atomic clocks. They include all of the functions normally found on premium counters: Time Interval, Frequency, Period, Totalize, Ratio, Time Interval Delay, and Pulse Width. Unlike many other boards of its kind, these instruments deliver worry-free results, and their inputs are high instrumentation quality, with the sensitivity and damage protection features common to all high quality counters.

The ability to precisely resolve frequency and time yields both increased accuracy as well as reduced measurement time. For example, with the GT200-10 you can determine any frequency to 0.1 part per million (seven digits) in just 1 mS, and resolve each time measurement to 100pS. Couple that with 2300 measurements per second, one of the fastest rates available and you can acquire more data in a single second than a typical GPIB counter can in one minute! Faster measurements and higher resolution, along with built-in statistics functions give you a more thorough analysis of your signal. Standard deviation, peak to peak jitter, or a graph of the measurements are available at the push of a button.


You can operate the GT200-10 counters just like conventional bench-top instruments with the standard Virtual Front Panel software which uses the power of a PC to speed and simplify data acquisition and analysis. You can view instant plots of your measurements or save them to disk without any programming. In system applications, you can read and control the GT200-10 from a test program using a set of library functions for C, a Windows DLL, or a labVIEW driver.


Because these instruments reside inside a PC, you can acquire superior counter capability for a remarkably low price. The GT200-10 compares very well, in terms of performance, flexibility, and ease of use, the premium priced instruments that sell for $4,000 to $12,000.



Channels A and B

  • Frequency range: DC to 100 MHz
  • Signal operating range: +5 V to -5 V
  • Coupling: DC
  • Impedance: Software selectable, 1 KΩ || 30 pF or 50Ω   
  • Auto Trigger Option


  • Frequency A or B
  • FastFrequency A or B
  • Width A or B
  • Time Interval A to B or Time Interval B to A
  • Totalize and Gated Totalize, A or B
  • Period A or B (Single Period)
  • Period A or B (Multiple Period Average)
  • Ratio A/B or B/A


Maximum Measurement Rate

  • For any PC:
    • 2300/sec for FastFrequency and all time modes
    • 1400/sec for Frequency and Period modes


  • Available on all modes, except Totalize
  • Arm setup time: Min. 40 ns before selected event

Time Base

  • Standard: 10 MHz TCXO
    • Temperature: ± 1 ppm, 0o to 50o Celsius
    • Aging: < 1 ppm/yr. or < 1×10-7/month
    • Supply voltage: < 1×10-9
    • Short term: <2×10-10
  • External reference input
    • Oscillator input (all modes)
    • Second signal channel (in single-channel measurements)