Download
Download

Download Manuals, Datasheets, Software and more:

DOWNLOAD TYPE
MODEL or KEYWORD

CMC251

Counter

The products on this datasheet are no longer being sold by Tektronix. Contact Technical Support for alternative products View Tektronix Encore for used test equipment Check support and warranty status for these products Find more support information for these products

Read Online:

Features & Benefits

CMC251
  • 1 Hz to 100 MHz (CH 1), 80 MHz to 1.3 GHz (CH 2)
  • ±1 ppm Time Base
  • Period Average, Period, Frequency, Totalize Self-test
  • Display Hold
  • Remote Start/Stop
  • One Year Warranty

Applications

  • Training
  • Manufacturing
  • Production Test
  • Field Repair
  • Bench Calibration and Repair
  • Product Design
  • Laboratory and Research
  • Education

CMC251

The CMC251 1.3 GHz Multifunction Counter measures the frequency of sine, square and triangle waves from 1 Hz to 1.3 GHz. The CMC251 also provides period, totalize and pulse width measurements. The counter has two input channels. Channel A is a standard 1 MΩ input for frequency measurements up to 100 MHz. Channel B is a 50 Ω terminated input for use in high-frequency systems. This counter is of interest to radio amateurs because of its ability to measure high-frequency systems. The temperature-compensated, crystal-controlled time base is stable to ±1 part per million per year.

Characteristics

Channel A

Frequency Range - 1 Hz to 100 MHz.

Sensitivity - 20 mVRMS, 1 Hz to 30 MHz; 50 mVRMS, 30 MHz to 100 MHz.

Attenuation - 3 V to 42 V (HI); 50 mV to 5 V (LO).

Max. Input Voltage - 1 Hz to 5 MHz: 42 V pk. 5 MHz to 100 MHz: 4.9 V pk.

Low Pass Filter - -3 dB at 100 kHz.

Impedance - 1.0 MΩ, paralleled by 40 pF.

Channel B

Frequency Range - 80 MHz to 1.3 GHz.

Sensitivity - 5 mVRMS, 80 MHz to 600 MHz; 15 mVRMS, 600 MHz to 900 MHz; 35 mVRMS, 900 MHz to 1.3 GHz.

Impedance - 50 Ω.

Max. Input Voltage - 1 VRMS.

Period

Range - Direct: 0.4 µs to 1.0 s. Prescale: 0.04 µs to 1.0 s.

Resolution - Direct: 100 ps to 100 ns. Prescale: 10 ps to 10 ns.

Min. Pulse Width - Direct: 0.2 µs. Prescale: 20 ns.

Frequency Range - Direct: 1 Hz to 2.5 MHz. Prescale: 1 Hz to 25 MHz.

Events Averaged (N) - 1, 10, 100, 1000, 10,000 cycles.

Totalize Range - 0 to 99,999,999.

Pulse Width

Range - 0.25 µs to 0.5 s.

Period Range - 100 ps to 100 ns.

Events Averaged (N) - 1, 10, 100, or 1000 cycles.

Time Base Stability

Temperature - <1 ppm from 0 °C to 40 °C.

10% Line Voltage Change - <0.4 ppm.

Accuracy

Frequency - ±(time base error + 1 count).

Period - ±(time base error + 1 count + trigger error).

Pulse Width - ±(time base error + 1 count + trigger error + 10 ns).

Plus

Selectable Slope - No.

Ratio CH A: CH B - No.

Display Hold - Yes.

Remote Start/Stop - Yes.

Time Interval CH A: CH B - No.

Safety - UL1244, CSA231, EN61010-1.

EMC - Meets Directive 89/336/EEC.

Ordering Information

CMC251

1.3 GHz Frequency Counter with High Stability Time Base.

Includes: Operator's manual, US power cord, one year warranty.

Available Accessories

10X Probe, 250 MHz - Order P6106A.

Tektronix Measurement Service

Tektronix CAL and REP service programs allow you to prepurchase genuine Return to Tektronix Services - ask your Distributor for details.