When the Double HRV Tolerance is checked that will most likely double the scan time. This parameter is useful when a slightly erratic heart rate is giving the software sustained error messages. If you need to use the Double HRV Tolerance option, I would reduce the scan range to get the time to a manageable range for your wife's ability to maintain stationary. If not, I would uncheck the box. A checked Single Scan box is what you want for a shorter scan. I'm not sure if any frequencies can be retrieved from the cancelled scan.
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