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The CRA-100 is a free running counter/timer continuously updating a Digital to Analog Converter [DAC] after each time base period. The major difference between the CRA-100 and a conventional rate meter is that while the conventional rate meter’s output reads counts per second [CPS] the CRA-100 outputs an analog signal representing counts per selected time base. Only the one (1) second time base will produce voltage directly corresponding to CPS. This time base will produce the 10 V output for 1024 CPS at the 10 bit range or 16,384 CPS for the 14 bit range. The other time bases will produce an analog output proportional to the input’s count rate.

An overload indicator lights up every time the maximum count is reached to warn the user that the analog output reached it’s limit and the time base needs to be reduced.

Maximum Count Rate 100 MHz
Input Pulses TTL (at least 5ns wide)
Pulse Pair Resolution 10ns
Counter Sizes 10bit or 14bit (Switch Selectable)
Time Base 10µs, 100µs, 1ms, 10ms, 100ms, 1s
Time Base Stability 100ppm
Synchronization Negative TTL Pulse or GND
Analog Output Signal 0V to +10V low impedance
Maximum Output Current 5mA
Output Voltage/1 Count 10mV/10 bit, 0.61mv/14 bit range
Dead Time 300ns


in US dollars
  Domestic International
CRA-100 $2,100.00 $2,625.00

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