johnny_software

Is it just my T637 that is poorly shielded? If I place it in the storage bin in the dashboard (the small one right by the shifter with the power outlet), when I'm on an HFL call, I can hear interference from the phone through the speakers. If I have the phone in the center arm rest or in my pocket, there's no interference...well, less, anyway.

What's worse, though, is that if the phone is near my computer, and I'm on a call, I can *see* the interference on my monitor. The image rolls. I can also hear the interference through my computer's speakers, which are ostensibly shielded themselves. The closer I put the phone to the PC, the worse it is.

Would somebody with a T637 be so kind as to try an experiment like this, either with their TL's HFL or their PC? I'd like to determine if it's just my phone that's bad or if it's just due to the design of the phone. My LG VX6000 never caused interference that I noticed. Thanks.

mobilezen

The magents inside the T637 are a lot smaller than those that are in your car, stereo, computer, etc. Comparing the LG and the T637...keep in mind CDMA and CSM use different frequencies as well that would cause other little mishaps.

Stewie

Yes, my T637 inteferes with stuff, though not normally my car stereo.

If I leave it on my nightstand when I go to sleep it will actually make noise through the clock radio speaker even though the radio is off!

But this weekend I was talking to my cousin who got a new Moto phone (non-Bluetooth) also from Cingular and he said his does the same thing. He thinks its the GSM network and not the Bluetooth.

Brewmaster

I see it with my T637 as well, but no where near as bad as my old Nextel ... I just use the bleeps to count the tumors that are on their way

johnny_software

Thanks guys. I guess I'm not alone...urgh.

Mobilezen: I'm not sure I understand what the size of the magnets (presumably you mean the ones driving the speakers) have to do with the RF signal being put out by the phone. But I do take your point that GSM has a different signal profile than CDMA and that it might be more prone to interfering with consumer electronics. The point of my post was to determine whether the interference was due to my particular handset or to GSM in general...given that I don't personally know anybody else who has a GSM phone

Stewie: I'm sorry if I was unclear. My phone doesn't interfere with the car stereo; it transmits a "noisy" signal through the stereo speakers when I'm on a Bluetooth call, which I assume is due to RF interference between the handset and some piece of electronics in the car.

Brewmaster: "It's not a tumah"

Attorney

What you're experiencing is symptomatic of all cell phones: If you place the phone near audio circuitry, the transmitted R.F. energy leaks into the nearby audio cabling and the radio case through mutual coupling.

It isn't that the T637 is not adaquately shielded: to the contrary - in order to completely resolve the interference problem, the phone manufacturers would need to limit the power output of the cell phone or make the internal antenna less efficient which will result in poor coverage. If anything, the TL's audio system could be better shielded against stray R.F. energy leakage.

I have three cell phones, including the T637 and each produces the same level of interference to the TL audio system when the phone is placed into one of the dashboard storage slots. It's simply the laws of physics at play.

Prior to becoming a lawyer, I worked as an R.F. systems engineer for AT&T and other communications companies in the broadband and broadcast industries.

Stewie

>>Stewie: I'm sorry if I was unclear. My phone doesn't interfere with the car stereo; it transmits a "noisy" signal through the stereo speakers when I'm on a Bluetooth call, which I assume is due to RF interference between the handset and some piece of electronics in the car.

Yeah, that's what I meant. It puts noise through the speakers. Does it to my notebook too if I leave the phone too close to it.

My friend has a Nextel through his work and that thing really messes with his car stereo.
In fact, he knows he's getting a call before the phone rings because the radio goes wacky!

johnny_software

Thanks for all the responses, guys. Really clears things up.

PG2G

I wonder if that's why those Klipsch PC Speakers I bought kept making loud ass howling noises randomly, even when powered down...

Damn T616.

mobilezen

I was just tossing out ideas. Everything that I have owned after the T637 never made my computer speakers or my stereo buzz...that's the K700i, S700i, P910i.

johnny_software

Your ideas are much, much appreciated

That's interesting about the K700i et al. Given Attorney's obviously well-informed description of how things work, does that mean that your newer toys don't get as strong a signal?

mobilezen

I found Attorney's description both entertaining and educational. I love learning and physics and aerodynamics are just plain sweet. In any case, I have in my possession right now a slew of phones...P910i, S700i, K700i, Motorola V180 (no bt...just a basic phone), Nokia 6310i, Nokia 6820, hmmm what else.... in any case, I'll run a quick test on all of them this weekend unless if someone is interested in buying my P910i or S700i....the k700 is mine.

irelandn2000

It's not the phone it's the signal it out puts. Any GSM phone will cause any system to have a noise every once in awhile. If I have my Sprint phone on my sub at home it will not make any noise. If I take it away and place my At&t phone there in its place it will make a slight noise. It's GSM only, not TDMA or CDMA or I-DEN. Just keep the phone away from the main part of the system and you will be fine.