Fujitsu LIFEBOOK Notebook User Manual page 63

Critical Points
When you connect a data / fax modem for the modem model PC, attach a core onto a
modular cable to reduce unnecessary radio to reduce unnecessary electromagnetic wave.
And insert the plug with the core to the PC unit.
1 Round a cable once immediately after the
modular cable plug.
Core Plug
2 Close the core.
Make sure not to pinch the cable when you
close the core.
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