A.When the speaker of a smartphone or tablet is too close
Mechanical watches are precision instruments made up of fine metal parts such as springs and gears. For this reason, people who own watches are probably careful enough to prevent them from being dropped or submerged in water, but did you know that there are actually traps lurking in unexpected places? It is an electronic product that generates magnetism. The reason why you have to be careful is that if the watch is exposed to magnetism, it will affect the position and movement of the internal movement parts, resulting in a drop in accuracy. This is called "magnetic banding".
General non-magnetic watches have a JIS (Japanese Industrial Standard) guarantee level of 1600 amperes per meter of magnetic resistance. It is defined as a class 1 anti-magnetic watch at 4,800 amperes per meter, and a class 2 anti-magnetic watch at 16,000 amperes per meter. It may not be clear from this figure alone, but a smartphone's speaker generates a magnetic field of about 16,000 amperes per meter, and a tablet terminal's speaker generates a magnetic field of about 32,000 amperes per meter. Resulting in. Therefore, if you place it in close contact with your smartphone's speaker, even a Class 1 anti-magnetic watch will be affected by the magnetic force and lose accuracy.
The photo shows a Rolex Milgauss with excellent magnetic resistance. By equipping the case with magnetic shields made of different ferromagnetic alloys, it has a magnetic resistance of approximately 80,000 amperes per meter.
Once a mechanical watch is magnetized by the influence of magnetism, it immediately loses accuracy, such as lagging or advancing, and it affects the accuracy in the future. Since it does not heal naturally, it is necessary to bring it to a watch repair shop and have it demagnetized. Therefore, it is especially important to keep the watch away from the speakers of smartphones and tablet terminals within 5 cm. By the way, quartz watches with analog display use a motor that uses the properties of magnets, and if it receives magnetism from the outside, it will affect the normal rotation of the motor, causing it to stop, lag, or advance. It's not broken, so if you move it away from the magnetism, it will return to its original accuracy. If you set it to the correct time again, there is no problem. Now that we are constantly exposed to magnetism, if you want to wear your watch without worrying about magnetism, it is important to choose an item with a higher degree of anti-magnetic properties.
Sentence ◎Yuki Matsumoto (editorial department)
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