1. 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.
2. The two biggest reasons for delayed scan finish are 1) poor connection so pulse isn't being "read" effectively., or 2) an irregular heart beat which causes some "out of range" readings, which then requires 4 readings in the normal zone prior to moving on.
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