A full scan is scheduled for about an hour, but depending on heart rate or irregularity, it may be significantly longer. I recommend using a Quarter scan for the first time to get a feel for how you respond to it.
The preset has a fixed number of frequencies and moves up one for each validly registered heartbeat. If consecutive beats are too erratic, the last one is discarded, the heart allowed to settle for several beats, then it continues. If this happens once, no big deal, but if it happens continuously, your scan never ends.
When the scan completes, the software knows to prompt the user if you've left the sound on both the computer and in the software.
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