When using an Ethernet cable that is 10 m or less, shielded cable is recommended.
(1) Make sure the printer is turned off.
(2) Affix the ferrite core onto the ethernet cable as shown in the illustration below.
(3) Pass the fastener through the ferrite core.
(4) Loop the fastener around the cable and lock it. Use scissors to cut off any excess.
10 cm
(maximum)
Ethernet cable
Ferrite core
Fastener 
(5)Connect the interface cable to the connector on the rear panel of the printer.
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