There are a few things to consider here.
The speed of the scan depends on your resting heart rate. So the estimated time of just over an hour may be close, but is just an estimate.
The scan needs to process 3,800 frequencies. For each of these frequencies it needs valid data from the pulse unit.
3,800 frequencies, scanned one every second (using an average heart rate of 60 BPM) would take 63 minutes.
However, if your resting heart rate is slower, the scan will take longer due the slower rate of data coming in from the pulse.
Furthermore, if you have at any time a bad data read from the pulse, it will pause the scan.
To resume, it needs 4 consecutive valid reads before continuing.
If you get one bad data read every 10 seconds, the scan will take 50% longer, and that is provided that you don't have more than one bad read. So now the 1 hr scan just turned into a 1 hr 30 min scan.
Sources that contribute to bad reads. Too loose of a sensor when worn, too tight (constricts blood flow), weaker pulse rate for that day, bad sensor location, etc.
To help with sensor placement, try to wear it on the left side as the pulse is stronger here.
Also, it helps to know that the sensor is taking readings by shining a light through your tissue, and monitoring the shadows that are cast by blood cells.
So don't wear the ear sensor over a piercing hole, wear the finger sensor on a finger nail (there are two dimples inside which need to be on flesh), etc.
I hope this helps you get your scans going again with good results.
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