Electronic – How to improve USB EMI insensitivity


I have several devices and some long cables on my PC's USB buses and every now and then I get a message like hub 6-0:1.0: port 2 disabled by hub (EMI?), re-enabling... on my Linux machine. Especially the devices on my desk (keyboard, mouse, 2 Arduino's) are being disconnected and reconnected. These devices respond to electric shutters for the windows, but also from passing motorbikes.

What can I do to improve immunity to EMI?

Tried ferrite cores on the mains cable of the shutters and some other equipment, but doesn't really improve much.

Bus 006 Device 025: ID 1a40:0101 Terminus Technology Inc. 4-Port HUB
Bus 006 Device 026: ID 0403:6001 Future Technology Devices International, Ltd FT232 USB-Serial (UART) IC
Bus 006 Device 027: ID 03f0:0324 Hewlett-Packard SK-2885 keyboard
Bus 006 Device 028: ID 046d:c046 Logitech, Inc. RX1000 Laser Mouse
  • Moved the keyboard off the hub, errors still appear.
  • Moved the mouse off the hub, errors still appear.
  • Moved the Arduino off the hub, errors still appear.

Eventually replaced the long extension cable with a shorter one and haven't had any errors for over a day. The longer cable is required to reach my desk though without cables dangling halfway in the air.

Best Answer

I took a rather thin USB extension cord, ran it 4 times through a ferrite core (one that comes in two halves in a piece of plastic and can be closed with a click) and ever since I haven't had any errors on my PC.