Review on JDS C 88Quake Earthquake Alarm by Abidzar Olivas

This is a simple alarm that detects vibrations, particularly those caused by earthquakes. This is a simple but effective mechanical design where the brass rod/pendulum hangs freely and with enough movement/vibration touches the sides of the brass V-notch/triangle around it (see photos of my review). This triggers the alarm circuit. The alarm is a loud metallic "Dingyyyy" sound that fades a few seconds after the last vibration. In a real earthquake with constant vibrations for many seconds or more, there will be a more or less continuous bell sound until the vibrations stop. The volume of the alarm clock is not adjustable, it is always loud. Given that this is an emergency (potentially life-saving) device, that might be a good thing. However, I find it too loud and would have preferred to have had a volume control. You can mount it to a wood or steel stud wall, but you'll need to turn the sensitivity down to avoid constant false alarms due to vibration from passengers (doors slamming, foot stomping, etc.). To be used at high sensitivity settings, it must be attached to a solid concrete wall. The block needs to be mounted perfectly vertical (straight up and down), but it will work if it's not perfectly vertical. Velcro strips allow you to change positions until you get it right, but velcro is a crappy attachment scheme. Sensitivity is adjusted by turning the white plastic screw on the front panel, increasing or decreasing the distance between the pendulum shaft and the V-notch. For high sensitivity, the pendulum should be literally a hair from the edges of the V-shaped groove. To check that it's set up correctly (both mounting orientation and sensitivity adjustment), lightly touch the device - an alarm should sound (see my video review). At very high sensitivity settings, even passing large trucks can be triggered. It can be annoying, but it means it works. The big question is: does it work? Yes, if configured correctly. He worked in the basement for about 15 seconds one morning, although I didn't feel a thing when I sat on the floor above. The next day, local news reported a magnitude 4.1 earthquake 135 km (84 miles) away at the exact time it happened.