BNC 1120 - 1pS Time Interval Counter User Manual
Page 10

Model 1120 - 1pS Time Interval Counter
NUT 012
Ed. 6
Date : 18/01/2011
BERKELEY NUCLEONICS
Page
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3.1.3. Event mode
In this mode the BNC 1120 counts events at Start and at Stop inputs.
Event counting can be gated:
Internally with a gate ranging of 1 second,
Externally through the duration of input gate.
The trigger level and slope for a transition event are adjustable on both the Start and
Stop inputs.
Event rate up to 10MHz can be counted with a maximum of 10 000 000 digits.
3.1.4. Auto-calibration
The BNC 1120 has a powerful built-in auto-calibration routine that compensates the
nonlinearities in time to digital converter. The auto-calibration is done through a software
command and takes about 30 seconds to be performed.
To calibrate the BNC 1120, send an Ethernet command or send CALIBRATE with the
front panel.
3.1.5. 10 MHz Time base
The accuracy of the BNC 1120 depends of the quality of the selected time base.
The internal 10MHz standard time base is an ovenized oscillator with stability of
±0.005 ppm.
A rear panel input allows you to connect an external 10MHz source as a time base.