MEASUREMENT BANDWIDTH: "Catch all the waves but don't be too far from shore"
In addition to checking the coherence of a tap-test you must also check that you have the proper bandwidth setting. There are three settings. The default is 5000 hz, the other two are 2000 and 10,000. After your first tap-test of an axis, click on the Freq. Response box. You will see a series of mode waves and it then should settle to almost flat line on the bottom up to 5000. If it doesn't and a wave is partially cutoff on the right, you need to increase the Frequency Bandwidth to 10,000, re-practice and re-tap the tool. You change the bandwidth by clicking on the set-up button and going to the sensors tab. If the waves settle to zero well before the 2000 mark and stay flat through 5000, you should decrease the bandwidth to 2000 to increase the measurement's accuracy. Do this and re-practice and re-tap the axis.