Why do so many USB and charging cables have a strange piece of plastic built into them?

Anyone who has ever held a charging cable in their hands will have noticed a strange, round plastic part. But what is it and what exactly does it do?

USB charging cables often come with a round part. Most of the time, the part is cylindrical and fairly inconspicuous.

Many have probably already noticed that notebooks, microphones and other devices also work with a USB cable without such a small cylinder on the cable. Why do you need it at all if you don’t need it at all?

Ferrite plastic part eliminates electrical noise

What does the part do? There is a ferrite core in the cylinder on the cable. The ferrite core acts as a noise filter, canceling out the electromagnetic waves before they can be radiated down the cable. You can imagine these waves like radio waves that interfere with other devices, for example your WLAN on your computer.

As a rule, these are two half-cylinders made of iron ferrite that are wrapped around the cable and filter out high-frequency interference. These are grey-silver if you cut open the cylinder.

This is to prevent electrical noise from leaking out from the connected device and affecting other devices that are also connected to the mains.

Such electrical disturbances on the PC are more common

Incidentally, such problems are not uncommon if you want to play on the computer. For example, one user had to hear strange voices coming from his computer, which only disappeared after he turned off his speakers.

Another player recently showed just how strong an effect such foreign “antennae” can have. Because he could always switch off his monitor with his soda can. You can read the full, crazy story right here on MeinMMO:

A gamer’s monitor keeps turning off – the culprit is a soda can next to his gaming PC

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