Example Night 2
3/31/2019 - This was recorded on the wall in my garage at 1 minute intervals. The y-axis is acceleration, an indicator of the vibration intensity. The x-axis is in time, roughly from 9:00 pm to 7:00 am.
Some nights it seems like the vibrations don't stop or only stop for short periods. On nights like this, we all wake up and fall asleep over and over. At 3:23 AM the series of on/off cycling is 6 minutes on every 20 minutes.
For comparison, some nights don't show measurements over 0.4 mm/s2, until the vibrations start in the morning (typically seems to be between 4:30 AM to 6:00 AM)
On a night like this, we really don't sleep much. I wake almost immediately every time the vibrations start. The baby and toddler wake a minute later. Even if the vibrations last only a few minutes, it causes problems. In this example, maybe by 4:30 AM, the kids are so tired that they sleep through it, but it is really disturbed sleep, they still toss and turn, and cry out.