Paper shredder interferes with wireless mouse/keyboard from over 20 ft away! - Page 1
Forum section: electronics / general

author: edy
author_rank: Super Contributor
timestamp: April 18, 2016, 07:54:47 pm
content: Hi folks,In my office I use a Logitech wireless mouse and keyboard. Whenever my front desk staff (who are at least 20+ feet away in another room) use the paper shredder installed under their desk, I can't move my mouse. The keyboard is not affected so much, but that could be that the battery strength on the keyboard is better than the mouse.Some times I am going absolutely crazy as I am trying to work and they are shredding sheet after sheet, basically making it impossible for me to use my computer as I can't move my mouse and click on anything.Ok, it's not as bad as that otherwise I would have tossed the shredder long ago. But still, shouldn't this be regulated? I don't remember where I bought it but it was a while ago and I guess the RF it puts out is dangerously high or exactly at the frequency that my wireless mouse operates?I've noticed if I use a fresh pair of AA's in my mouse it isn't too bad... but after a while it becomes more noticeable. Still, my mouse is at most 2 feet away from the computer.

author: Cubdriver
author_rank: Unknown
timestamp: April 18, 2016, 07:59:26 pm
content: Perhaps see if you could put one of those clip-on clamshell ferrite noise supressors on the linecord where it emerges from the shredder and see if that helps?-Pat

author: Augustus
author_rank: Regular Contributor
timestamp: April 18, 2016, 08:02:59 pm
content: Use a USB extension cable and move the receiver dongle onto your desk

author: Zbig
author_rank: Frequent Contributor
timestamp: April 18, 2016, 08:35:38 pm
content: Not once but at least twice my colleague has deleted a bunch of unread e-mails when his wireless keyboard git stuck in the "DELETE key down" state.

author: David_AVD
author_rank: Super Contributor
timestamp: April 18, 2016, 08:43:52 pm
content: Quote from: Augustus on April 18, 2016, 08:02:59 pmI've done this with a couple of computers. A P-clamp fixes the end of the USB cable (with receiver plugged in) to the underside of my wooden desk.

author: Zbig
author_rank: Frequent Contributor
timestamp: April 18, 2016, 08:51:09 pm
content: Quote from: David_AVD on April 18, 2016, 08:43:52 pmSwitch that for a small USB hub and you get a few extra sockets for USB sticks and such.

author: edy
author_rank: Super Contributor
timestamp: April 18, 2016, 08:56:32 pm
content: My receiver is already on my desk, just under the monitor. Normally it works fine. The shredder is the only device in the office that causes problems when active. Lack of compliance with RF interference guidelines? Heck, all it is supposed to do is activate a small motor.... how does it emit so much RF noise? Is there any easy way to pick it up on an oscilloscope? Can I set up an antenna and view it on a 100 Mhz scope?

author: suicidaleggroll
author_rank: Super Contributor
timestamp: April 18, 2016, 09:36:11 pm
content: Quote from: Augustus on April 18, 2016, 08:02:59 pmOr switch to a wired keyboard/mouse?I never did understand the draw of the wireless ones. They always seem to be more of a nuisance than anything else...characters not making it through, characters getting stuck and repeating on their own, interference locking out the interface, batteries need to be replaced every so often, etc. For an application where the keyboard/mouse and the computer are separated by a significant distance (eg: HTPC) then I get it, but for a work machine at a desk? Why wouldn't you just use a wired keyboard/mouse since nothing is going anywhere anyway?

author: David_AVD
author_rank: Super Contributor
timestamp: April 19, 2016, 12:03:50 am
content: I use my mice a lot and hate using a corded type. A wireless keyboard is also handy on a bench so you can pop it out of the way without the cord to worry about.Having use wireless keyboards and mice for years I can't say I've had any issues with missed characters, etc. The mouse gets a bit intermittent when the battery is almost dead, but that's bot really a fault.

author: Brumby
author_rank: Unknown
timestamp: April 19, 2016, 02:02:41 am
content: Quote from: David_AVD on April 19, 2016, 12:03:50 amPretty much the same for me.My receiver is mounted on the underside of my wooden desktop. Out of the way and works well.

author: Rerouter
author_rank: Super Contributor
timestamp: April 19, 2016, 02:35:55 am
content: It would be broadband noise from the shredder due to it likely having almost no internal filtering for motor noise,It should have an EMI socket (they have always been more for keeping noise in), and likely for the torque required it would be a DC motor, if so should have a nice big filter cap across the brushes to soak up the transitions and the case of the motor should be grounded, with some small caps between the brushes and case,

author: Jeroen3
author_rank: Super Contributor
timestamp: April 19, 2016, 07:24:05 am
content: Quote from: Augustus on April 18, 2016, 08:02:59 pmThe wireless signal is very very low power. It's has to run months on one or two AA batteries. Consider the wireless to not be of any more than 30cm line-of-sight range.It's a convenience not having a cable, but don't expect it to work flawless when the receiver is buried at the back panel of your desktop.Quote from: edy on April 18, 2016, 08:56:32 pmNot that surprising if there is a brush motor inside. The brushes will spark all over the place and cause all sorts or noise.Ever noticed how a petrol engine could severely disrupt radio/video and WiFi communications? Same thing: sparks.Relevant video about logitechHow tonotembed a youtube video?