Measurement Functions - Racal Instruments 2251A Operator's Manual

1.2

Measurement Functions

1.2.1 The following measurement functions are available in the 2251A Counter.
1.2.1.1 Frequency A. This provides frequency measurement up to 200 MHz using input A.
1.2.1.2 Frequency B. This provides frequency measurement up to 160 MHz using input B.
1.2.1.3 Period A. This provides period measurement from 5 nS using input A.
1.2.1.4 Period B. This provides period measurement from 6.25 nS using input B.
1.2.1.5 Time Interval. This provides Time Interval measurements in two modes; Separate mode,
where events at inputs A and B start and stop the measurement, and Common mode, where
events at input A both start and stop the measurement.
1.2.1.6 Total A by B. This counts the number of events occurring at input A between events at input
B.
Manual Totalize. This counts the number of events between device dependant
commands to open and close the counter's gate.
1.2.1.7 Ratio A/B. This measures the ratio of the frequencies applied to inputs A and B.
1.2.1.8 Rise/Fall A. This measures the rise or fall time of a signal at input A, depending on the slope
selected.
1.2.1.9 Pulse Width A. This measures the interval between successive rising to falling, or falling to
rising edges, depending on the trigger slope conditions specified.
1.2.1.10 Phase A rel B. This measures the phase difference between signals at inputs A and
B.
1.2.1.11 Check mode. This mode allows the user to verify the 2251A is operating correctly.
Note the capabilities of the Check mode may be extended by the use of special
functions.
1.2.1.12 Frequency C. The frequency measurement range of the 2251A is extended to 1.3
GHz with Option 41.
1.2.1.13 Ratio C/B. Frequency ratio measurements up to 1.3 GHz are available when Option
41 is fitted to the 2251A.
1-2
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com