AGILENT 35670A
Supplemental Operator’s Guide
window time constant of 62.5 ms. To set up these Force/Response windows, follow these steps:
•Press the [Window] hardkey.
•Press the [FORCE EXPO] softkey (F4).
•Press the [FORCE EXPO SETUP] softkey (F6).
•Press the [FORCE WIDTH] softkey (F6).
•Enter 36 and then press the [mS] softkey (F2).
•Press the [EXPO DECAY] softkey (F7).
•Enter 62.5 and then press the [mS] softkey (F2).
To view the effects of theForce/Response window,
•Press the yellow [Start] hardkey.
•Tap the structure with the hammer.
Observe the time trcaes. Compare them to their windowed time records. Determine if the Force/Response windows met their object. Adjust windows if necessary. If it appears that no window would be required, then it is possible to test with a “UNIFORM” (meaning factor of 1) window instead of a force/response window. To select a UNIFORM window,
•Press the [Window] hardkey.
•Press the [UNIFORM] softkey (F3).
Displaying Hammer Test Results
The results of hammer testing are frequency response functions, and the indicator of measurement quality is coherence. These traces can be set up as follows:
•Press the [Disp Format] hardkey.
•Press the [UPPER/LOWER] softkey (F3).
•Press the [Active Trace] hardkey.
•Press the [A] softkey (F1)
•Press the [Meas Data] hardkey.
• Press the [FREQ RESP 2 / 1] softkey (F6)
•Press the [Scale] hardkey.
•Toggle the [AUTOSCALE ON OFF] softkey (F1) until ON is highlighted..
•Press the [Active Trace] hardkey.
•Press the [B] softkey (F1)
•Press the [Meas Data] hardkey.
•Press the [COHERENCE 2 / 1] softkey (F7)
Averaging
Averaging is a very effective technique for improving the quality of frequency response measurements. A minimum of four averages reduces noise and variance
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