Warthog Systems LabHelper X
Y-axis scaling; sample averaging
This operation sets the upper and lower Y-axis limits for the screen display of a particular channel. The default values are -5 to 5. If you pick one of the pre-defined voltage conversions, the Y-axis scaling will be preset automatically. Similarly, if you use the 'Direct calibration' function, scaling will be based on the range of values used during the calibration procedure. If you wish to set a different scaling from the default or the pre-defined values, enter your choices in the two edit fields before you click the 'Selection OK' button.
Note that the scaling you select applies only to the SCREEN display. Even if values are offscale on the screen, they will still be recorded correctly in the data file -- provided they do not exceed the voltage limits of the A to D hardware.
These menu options let you select the number of voltage readings to be averaged for each recorded Chart sample value. Averaging is useful for eliminating background electrical noise, or other short-term variation that may obscure long-term trends. It may also be used to obtain single integrated readings from long intersample intervals. Some important aspects of averaging:
NOTE: sample averaging is automatic if you have selected Oscilloscope plus Chart mode. In this mode a voltage reading is made from ALL channels when the oscilloscope reading is made. When the sample interval for chart channels has elapsed, the stored readings for the chart channels are averaged, plotted, and saved. Thus the number of samples averaged for chart channels is roughly equal to the value:
chart sample interval / oscilloscope sample interval
Use of this method simplifies calculations and allows the highest possible oscilloscope sampling rate.