TELECOM Digest OnLine - Sorted: Re: Nokia 6010 Reporting in to Mama -- Radio Interference?

Re: Nokia 6010 Reporting in to Mama -- Radio Interference?

Phil McKerracher (phil@mckerracher.org)
Sat, 05 Mar 2005 00:24:39 GMT

Joseph <JoeOfSeattle@yahoo.com> wrote in message
news:telecom24.94.8@telecom-digest.org:

> On Thu, 03 Mar 2005 15:59:30 -0500, Ted Koppel <tkoppel@adelphia.net>
> wrote:

>> My new Nokia 6010 has an interesting and somewhat annoying habit. If
>> it's anywhere within a 5 foot radius of my PC speakers, I can hear it
>> periodically transmitting something (sort of a rhythmic
>> dum-diddy-dum-diddy-dum-dum-dum). Sounds like static, but definitely
>> with a paced rhythm. I haven't timed the intervals exactly, but it
>> seems to take place every 17-20 minutes. In a related activity, I
>> hear a big burst of static on my PC speakers, and then some rhythmic
>> noise, about 5-7 seconds before the cell phone begins to ring.

>> This is the first cell phone I've had that caused these noises. Do I
>> have a mutant phone? Is this anything to be concerned about?

> It's not just the Nokia 6010. *Any* GSM will exhibit the
> characteristics you refer to. It's the phone communicating with the
> system periodically...

True. I was told by a contact at ETSI (the organisation that defined
many of the GSM standards) that this was originally an oversight --
they had not realised that the modulation scheme was effectively 100%
amplitude modulation, which would be "detected" by any rectifying
circuit nearby. It caused a lot of consternation in the early days.

The "solution" they eventually agreed was to reduce the power
transmitted by the phones by a factor of 10. This had been proposed
anyway, to reduce the cell size and hence increase system capacity
(also to increase battery life).

Phil McKerracher
www.mckerracher.org

Post Followup Article Use your browser's quoting feature to quote article into reply
Go to Next message: Mark Atwood: "Re: Nokia 6010 Reporting in to Mama -- Radio Interference?"
Go to Previous message: Jack Decker: "It's Degrading: VoIP Firms Urge More FCC Action"
TELECOM Digest: Home Page