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 MO input for frequency measurements up to 100 MHz. Channel B is a 50 O 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. Features & Benefits 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

Performance Characteristics
• Form Factor Benchtop
• Number of Channels 2 ch
• Minimum Frequency, Ch. 1 1 Hz
• Maximum Frequency, Ch. 1 100 MHz
• Sensitivity, Channel 1 50 mV
• Maximum Input Voltage, Ch. 1 4.9 V
• Input Impedance, Ch.1 1 MOhm
• Minimum Frequency, Ch. 2 80 MHz
• Maximum Frequency, Ch. 2 1.3 GHz
• Sensitivity, Channel 2 35 mV
• Maximum Input Voltage, Ch. 2 1 V
• Input Impedance, Ch. 2 50 Ohm
• Time base stability 1 /yr
Measurements/Features
• Attenuation - 3 V to 42 V (HI); 50 mV to 5 V (LO)
• Low Pass Filter - -3 dB at 100 kHz
• Attenuation - 3 V to 42 V (HI); 50 mV to 5 V (LO)
• Pulse Width Range - 0.25 µs to 0.5 Second
• Selectable Slope - No
• Ratio CH A: CH B - No
• Display Hold - Yes
• Remote Start/Stop - Yes
• Time Interval CH A: CH B - No
• EMC - Meets Directive 89/336/EEC
Programmability/Connectivity
• User Interface Proprietary
Life Cycle Data
• Out of Production May-26-2002
Compliance
• CE Compliance Compliant
• UL Compliance Not compliant
• Safety Issue UL1244, CSA231.
Power Requirements
• Input Power USA (110V/60Hz)
Standard Accessories
• Operator manual /Operator manual /Qty:1