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#160175 - 06/10/05 02:37 PM keyfobs and computers
ruggedscotty Offline

Registered: 06/09/05
Posts: 17
Loc: Edinburgh Scotland
Im trying to locate some information - and hope that you can help me here, I saw an article a long time back now that talked about the possibility of car alarm remote fobs interferring with computers. I cant find the blessed thing now and its annoying the c**p outta me.

Im not talking about home PC's either but proper servers and computer room equipment, Ive seen the effect that mobiles and radio walkie talkie can have and well I just think that there is a risk with key fobs, trying to back this up and refind that article if I can - anyone seen anything ?

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#160176 - 06/10/05 07:56 PM Re: keyfobs and computers
gfretwell Offline


Registered: 07/20/04
Posts: 9058
Loc: Estero,Fl,usa
I think it is a non-issue. For most of the 80s and 90s I carried an 800mz Motorola PT (the first "blackberry" type device) and originally they had dire warnings about using them in the computer room. Of course we still did. After a few years they decided they had never found a case where it bothered anything, even when we were actually under the covers.
These things were a lot more powerful than a cell phone or key fob (5 watts) They were also listed as being "intrinsically safe" for you classified location fans.
This is the same BS that they spread about cell phones crashing airliners and blowing up gas pumps.
Greg Fretwell

#160177 - 06/11/05 07:23 AM Re: keyfobs and computers
hbiss Offline

Registered: 12/16/03
Posts: 893
Loc: Hawthorne, NY USA
Key fob transmitters are so low in power that I can't believe they would cause any problems with computers. We carry Nextels and they don't cause a problem except up close with some audio equipment.

The fact that you mention servers and computer room equipment makes me even more certain that this is just a myth probably started by some computer geek with a pocket protector being overly protective of his babies.


#160178 - 06/11/05 07:30 AM Re: keyfobs and computers
brianl703 Offline

Registered: 05/16/05
Posts: 165
Loc: Manassas, VA
Computers are far more likely to interfere with a radio device than the other way around.

That goes double for the "FCC Class A" certified computers used in commercial environments--they are allowed to radiate more than an "FCC Class B" certified computer intended for residential use.

Any computer geek who thinks that a keyfob would interfere with their computer ain't much of a geek, but more like a clueless newb.

#160179 - 06/11/05 12:33 PM Re: keyfobs and computers
mkoloj Offline

Registered: 01/03/05
Posts: 134
I found something of interest while working for my former employer. We had company issued cel phones that we would hate answering in the middle of the day because the boss would have us running out to the truck checking VIN #'s or something that to an employee just seemed annoying. One day I am working in a daa center at one of our accounts and I put my cel phone on top of a server in a cabinet and the cel service went from 5 bars to no service when it came within 6" of this one Compaq server. Needless to say I was never again to be bothered while at that customer's site.

[This message has been edited by mkoloj (edited 06-11-2005).]

#160180 - 06/12/05 02:24 AM Re: keyfobs and computers
pauluk Offline

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
I'd go with the comment already made that these things are so low-powered that the chances of affecting a computer are about nil.

I've had RF sources radiating much stronger fields than you would get from these keyfobs next to computers with no effect.

#160181 - 06/12/05 03:55 PM Re: keyfobs and computers
gideonr Offline

Registered: 12/18/04
Posts: 152
Loc: Edinburgh, Scotland, UK
Keyfobs are (in most countries) limited to 10mW compared to several watts for cellphones.

You would have to be very lucky, or unlucky, to cause some kind of effect on a computer with a cellphone, but it is possible if there is a cable that happens to be just the right length that it resonates at the cellphone transmit frequency. Usually it's just the monitors that show cellphone signals (and radiate the interference). If the computer system were in a bank, I for one would prefer not to take the chance with it.


#160182 - 06/13/05 10:47 AM Re: keyfobs and computers
ruggedscotty Offline

Registered: 06/09/05
Posts: 17
Loc: Edinburgh Scotland
I have seen a UPS take a fit when a radio was near it - so i do know that some RF can in the wrong place wreck havoc - doing risk assesments and trying to work out what can and cant be taken into a computer hall in regards to these things. Phones are a major no-n0 as I have seen the effect that they have had on some units but the key fob was something that I was trying to find out about.

Thanks for the help and assistance.

#160183 - 06/13/05 12:25 PM Re: keyfobs and computers
Prodiem Offline
Junior Member

Registered: 06/01/05
Posts: 3
Loc: Santa Maria, CA, USA
I have been working out at a site with fringe service. We decided to purhase and use some Radios, nice 5 mile range ones too. I still haven't bothered to find the actuall output on them but once in the server room I replied to a call and one of the servers nearest to me rebooted. But after retrying it several times I never got anything else to happen. (Right moment in time)
Also once I had my cell phone next to my car stereo waiting to drive back into signal to make a call. Stereo went nuts when it got reconnected. Now that I can say was damaged as the Left speakers are blown. (Volume was set to 100%, 6 month old loved that one)
Both of these occations were either right on top of or within inches of to cause the interference, and have never been done again despite trying. Still I am incharge of the server room, and I respect the possibility, and keep a few feet between me and them when useing an radio.

#160184 - 06/14/05 08:35 AM Re: keyfobs and computers
ruggedscotty Offline

Registered: 06/09/05
Posts: 17
Loc: Edinburgh Scotland
This is the problem that we face - sometimes it does it sometimes it doesnt, it all depends on where the machine is in its process and what it is doing at that time. With servers handling processes at the time that could be crutial to the business the implications are huge - talking £millions£ here and that is something that we want to avoid, remove the risk manage it and ensure that the impact remains minimal.
Also with other equipment you have the issues regarding power - a UPS handles a hell of a lot of power and to have that taking a fit well you really wouldnt want to be near it, radios phones and key fobs being generally about the person, means that you would be close proximity. Not a great place to be.



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