AGILENT 35670A
Supplemental Operator’s Guide
•Press the [XDCR UNIT CONVERT] softkey (F4)
•Press the [inch (DISP)] softkey (F7)
•Press the [Scale] hardkey.
•Toggle the [AUTOSCALE ON OFF] softkey (F1) until ON is highlighted.
This accomplishes the equivalent of multiplying “g” by 386.4 to get “inches per second squared” (ips^2), and dividing by (jω)^2 to integrate twice in the frequency domain to get displacement.
Math Functions and XDCR UNIT CONVERT
When you have specified a “provided” transducer label using XDCR UNIT SETUP that is a “motion” engineering unit such as:
g inch/s^2 inch/s inch mil m/s^2 m/s
m
then do not try to convert acceleration to displacement using Analysis: Math Function and divide by (jω). Instead use the above example to convert directly using XDCR UNIT CONVERT in Trace Coord, Y UNITS. If this is attempted with Math Functions, the analyzer will sense that a power spectrum of a known unit “label” is being integrated or differentiated and will do it using trace coordinates anyway. It is easier to use the provided capability in XDCR UNIT CONVERT.
Converting Frequency Response Units to Compliance
Unlike power spectrum measurements, frequency response measurements cannot be automatically converted into other units. Howvere, it is often desired to express a frequency response result as the ratio of displacement to force, which are units of compliance, instead of acceleration to force, which are units of 1/mass. To convert a frequency response measured as “g/lb.” into terms of “inch/lb.”, then proceed as follows:
Converting “g” to “inch/s^2” requires multiplication by 386.4. This must be entered as a constant. Converting “inch/s^2” to “inch” requires double integration in the frequency domain by dividing by (jω) two times. These steps may be entered as follows
•Press the [Analys] hardkey.
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