gsm & hearing aids

On Tue, 17 Feb 2004 09:13:35 +1100, "John Henderson"
<jhenRemoveThis@talk21.com> wrote:

>"Tom" wrote:
>
>> Most of the carriers in my area use CDMA. That is fortunate
>> for me since the TDMA phones that I have tried cause so much
>> interference with my hearing aids that it is impossible for me
>> to use them.
>>
>> I've only tried one GSM phone, but it caused similar
>> interference. Is this a common problem with all GSM phones and
>> hearing aids, or might I just have had a bad one?
>
>You might find useful information at:
>http://www.gsmworld.com/using/health...ngaidfaq.shtml
>
>John
>
It is going to require careful design of the hearing to avoid the
problem with GSM, outside the USA where EMI shiedling requirements are
much lower, you can hear GSM phones being polled, and before they
start to ring, you often hear the 217 Hz tone on radios (even if
turned off!), TV's and anything else with a speaker!

Normall FCC compliance would prevent a problem in the USA, but a
Hearing aid is exempt because it is intended for mobil use.

matt weber wrote:
> On Tue, 17 Feb 2004 09:13:35 +1100, "John Henderson"
> <jhenRemoveThis@talk21.com> wrote:
>
>
>>"Tom" wrote:
>>
>>
>>>Most of the carriers in my area use CDMA. That is fortunate
>>>for me since the TDMA phones that I have tried cause so much
>>>interference with my hearing aids that it is impossible for me
>>>to use them.
>>>
>>>I've only tried one GSM phone, but it caused similar
>>>interference. Is this a common problem with all GSM phones and
>>>hearing aids, or might I just have had a bad one?
>>
>>You might find useful information at:
>>http://www.gsmworld.com/using/health...ngaidfaq.shtml
>>
>>John
>>
>
> It is going to require careful design of the hearing to avoid the
> problem with GSM, outside the USA where EMI shiedling requirements are
> much lower, you can hear GSM phones being polled, and before they
> start to ring, you often hear the 217 Hz tone on radios (even if
> turned off!), TV's and anything else with a speaker!

I hear this all the time in my car radio, tuned to the lower end of FM
with the handset in it's dash cradle. Sometimes it's an incoming call
and sometimes not. When the 6340i is in geek mode, the 0101 screen show
SDCC instead on CCCH while this 'noise' is heard on the car radio - and
often predictable on some street locations. I've always presumed it's
the handset chatting away with a BTS for reasons I'm not certain I
actually care about, but I don't hear this when using the CD player nor
with the radio off.

>
> Normall FCC compliance would prevent a problem in the USA, but a
> Hearing aid is exempt because it is intended for mobil use.


--
jer email reply - I am not a 'ten' ICQ = 35253273
"All that we do is touched with ocean, yet we remain on the shore of
what we know." -- Richard Wilbur

Thanks for the info. I guess that I am fortunate that most of the
carriers in my area use CDMA. The backlights sometimes cause
interference, but the phones themselves do not. I wonder what the
hearing-impaired to in Europe.

Again, thanks.

tom

tom.cowdery@bigfoot.com (Tom) wrote in message news:<f00f4c38.0402170555.712182ae@posting.google. com>...
> Thanks for the info. I guess that I am fortunate that most of the
> carriers in my area use CDMA. The backlights sometimes cause
> interference, but the phones themselves do not. I wonder what the
> hearing-impaired to in Europe.

Savor a much simpler way of life without the need for cell phones?
;-)

Seriously, I suspect headset use is more prevalent. Might not the
speaker in a headset be compatible with the T-coil in a hearing aid?
(Provided you use a headset that fits over the ear rather than wedged
in it!) Plus, leaving the handset on your belt might minimize any RF
interference.