Where can I buy an earthquake alarm that uses P wave detection?

Hey Anon, Just a wild guess... do you live near a seismographic active area?? (earthquakes)..near Yellowstone maybe..San Fransisco ..or Memphis area..??
Just a thought.. https://earthquake.usgs.gov/monitoring/seismograms

Tsunamis happen when there is an underwater earthquake, causing the ocean floor to move violently up or down. When the ocean floor moves like that, the water above it has to go somewhere so it spreads out in a very fast wave. The wave is a tsunamis.

It doesn't. In deep water a tsunami isn't even a big wave. A boat can go right over one without even noticing it. The problem is when the tsunami hits shallow water.

Unlike normal waves which are only on the surface, a tsunami goes all the way to the bottom. So what happens when a miles (or kilometers) high wall of water hits the shallower seabed near a shore? It piles up. Not miles high, of course, since the water crumbles, but still rather high. And with the forward momentum it just keeps piling up and driving forward.

Random is truly a difficult problem to solve, if no pattern of failure can be detected. It sounds as though the alarm may be at fault. Is the alarm on and set to radio, CD, or beep? If radio, that could pinpoint the problem. If you have another, mechanical alarm, use it for a couple nights with the Bose Wave alarm off. If the Bose still acts up, then it isn't the alarm. Try unplugging the unit, waiting at least 30 seconds, and plugging it back in, which will cause you to need to reset the alarm. Alternately, remove the Bose cover and blow out dust. I find the Bose susceptible to dust as a cause of malfunction, which may point to the cause being the compact design of the unit. Good luck.

what happens when an earthquake alarm goes off in japan?
read the article to find out!
http://www.japan-talk.com/jt/new/when-an-major-earthquake-alarm-goes-off-in-Japan

An earthquake alarm provides an early warning by detecting an earthquake's soundwaves before the shear wave hits your area. The alarm will detect a quake that is even many miles away! A loud alarm will then go off.

They cost anywhere between $20 to $100. $30 is the average.

Earthquake alarms are important if you live in an earthquake prone area and if you are a deep sleeper. Some people can sleep through an earthquake and risk injury, therefore an alarm will help wake you up.

Tsunami is a Japanese word meaning ''huge wave'' that refers to a series of large ocean waves. It is caused basically due to underwater earthquake, Richter magnitude exceeding 7.5 to produce a destructive tsunami.


Concept can be summarized as follow:


The earth is constantly moving on large tectonic plates. When these tectonic plates moves past each other, collide and/or slide under one another an earthquake results. This is what happened with the recent tsunami that devastated Southern Asia. A massive earthquake in the Indian Ocean measuring 10.0 on the Richter scale jolted the seabed causing the sudden displacement of a very large volume of water. The earthquake temporarily produces a fluctuation in the mean sea level of a specified area. Waves quickly form as the displaced water tries to recapture equilibrium by filling the vacuum that was created. Tsunamis are a series of extremely long waves that are created after a large volume of water is displaced. The amount displaced must be significant enough to create waves underwater in the vast ocean. Waves are formed as the displaced water mass moves under the influence of gravity to regain its equilibrium. The larger the displacement, the larger the wave generated.

The PWM IC is an SG3525. Which IC are you calling the protection IC?