On 2007-04-25, DougSlug wrote:
In my office we often experience instances of a "galloping" sort of buzz
periodically coming from the PC speakers near co-workers who have Cingular
GSM cell phones.......

Might be bees screaming in agony.

nb

"DougSlug" wrote in message
...
In my office we often experience instances of a "galloping" sort of buzz
periodically coming from the PC speakers near co-workers who have Cingular
GSM cell phones. A preliminary Web search turns up many instances of this
problem. My understanding is that these phones periodically communicate
with the network, and during these brief bursts the carrier is modulated
at around 200 Hz resulting is a clear, repeatable buzz pattern. How is
this buzz getting into the PC speaker amplifier, and, more importantly,
how can it be prevented?

Thanks,
Doug

every so often all gsm phones communicate with the tower. Thats when the rf
interferes with stuff or when its about to ring. Just keep a little farther
away from other appliances.

"Sarge" wrote in message
...

"DougSlug" wrote in message
...
In my office we often experience instances of a "galloping" sort of buzz
periodically coming from the PC speakers near co-workers who have
Cingular GSM cell phones. A preliminary Web search turns up many
instances of this problem. My understanding is that these phones
periodically communicate with the network, and during these brief bursts
the carrier is modulated at around 200 Hz resulting is a clear,
repeatable buzz pattern. How is this buzz getting into the PC speaker
amplifier, and, more importantly, how can it be prevented?

Thanks,
Doug

every so often all gsm phones communicate with the tower. Thats when the
rf interferes with stuff or when its about to ring. Just keep a little
farther away from other appliances.

Thanks, but you basically just re-stated the problem. I was hoping to get a
more technical explanation of the mechanism by which the noise is coupled
with the goal of using that information to determine what techniques might
be used to prevent it. Keeping it a little farther away isn't usually an
option because the owner keeps it clipped on his belt, and it isn't
practical for him to remove it when he is at his workstation since he comes
and goes all day. I'm figuring that use of a ferrite on the amplified
speaker power cord is likely to be the most effective solution.

"DougSlug" wrote in message
...
In my office we often experience instances of a "galloping" sort of buzz
periodically coming from the PC speakers near co-workers who have Cingular
GSM cell phones. A preliminary Web search turns up many instances of this
problem. My understanding is that these phones periodically communicate
with the network, and during these brief bursts the carrier is modulated
at around 200 Hz resulting is a clear, repeatable buzz pattern. How is
this buzz getting into the PC speaker amplifier, and, more importantly,
how can it be prevented?

GSM is your problem. Find a cell company that doesn't use the GSM standard,
and you problems will go away; and just maybe the honey bees will survive...

GSM is junk, and should have never seen the light-of-day. The wife's phone
uses GSM, and it interferes with EVERYTHING. Any speaker in the house
buzzes, doesn't matter what it's connected to, screws up the picture on the
TV, computer monitor, etc. Causes all kinds of interference to nearly every
radio in the house (communication or otherwise).

Thankfully my cell carrier uses CDMA, and I don't have ANY of these types of
issues, or any others for that matter. To top it off, I can use my phone in
MANY locations that hers will not work.

"PowerHouse Communications" wrote in message
...

"DougSlug" wrote in message
...
In my office we often experience instances of a "galloping" sort of buzz
periodically coming from the PC speakers near co-workers who have
Cingular GSM cell phones. A preliminary Web search turns up many
instances of this problem. My understanding is that these phones
periodically communicate with the network, and during these brief bursts
the carrier is modulated at around 200 Hz resulting is a clear,
repeatable buzz pattern. How is this buzz getting into the PC speaker
amplifier, and, more importantly, how can it be prevented?

GSM is your problem. Find a cell company that doesn't use the GSM
standard, and you problems will go away; and just maybe the honey bees
will survive...

GSM is junk, and should have never seen the light-of-day. The wife's
phone uses GSM, and it interferes with EVERYTHING. Any speaker in the
house buzzes, doesn't matter what it's connected to, screws up the picture
on the TV, computer monitor, etc. Causes all kinds of interference to
nearly every radio in the house (communication or otherwise).


But why is this? I'd like to understand what GSM does that the other
systems don't do. Is a higher transmit power needed from the handset for
some reason? Guess I need to do some more background research.

- Doug

GSM uses Time division multiple access a.k.a TDMA with a 30kc wide signal.
The carrier freq it uses hops around with in a band near 1.9Ghz as CW
packet bursts.

Unshielded speaker components act as diodes, which in turn acts a AM
radio detector,
and turn your speaker into a receivers of the AM resulting signal.
That is the noise you hear.

I hope that helps.

-SN


DougSlug wrote:
"PowerHouse Communications" wrote in message
...

"DougSlug" wrote in message
...

In my office we often experience instances of a "galloping" sort of buzz
periodically coming from the PC speakers near co-workers who have
Cingular GSM cell phones. A preliminary Web search turns up many
instances of this problem. My understanding is that these phones
periodically communicate with the network, and during these brief bursts
the carrier is modulated at around 200 Hz resulting is a clear,
repeatable buzz pattern. How is this buzz getting into the PC speaker
amplifier, and, more importantly, how can it be prevented?

GSM is your problem. Find a cell company that doesn't use the GSM
standard, and you problems will go away; and just maybe the honey bees
will survive...

GSM is junk, and should have never seen the light-of-day. The wife's
phone uses GSM, and it interferes with EVERYTHING. Any speaker in the
house buzzes, doesn't matter what it's connected to, screws up the picture
on the TV, computer monitor, etc. Causes all kinds of interference to
nearly every radio in the house (communication or otherwise).



But why is this? I'd like to understand what GSM does that the other
systems don't do. Is a higher transmit power needed from the handset for
some reason? Guess I need to do some more background research.

- Doug

This is normal. Just keep the phone away from the speakers.
"DougSlug" wrote in message
...
In my office we often experience instances of a "galloping" sort of buzz
periodically coming from the PC speakers near co-workers who have Cingular
GSM cell phones. A preliminary Web search turns up many instances of this
problem. My understanding is that these phones periodically communicate
with the network, and during these brief bursts the carrier is modulated
at around 200 Hz resulting is a clear, repeatable buzz pattern. How is
this buzz getting into the PC speaker amplifier, and, more importantly,
how can it be prevented?

Thanks,
Doug

"DougSlug" wrote in message
...
In my office we often experience instances of a "galloping" sort of buzz
periodically coming from the PC speakers near co-workers who have
Cingular GSM cell phones. A preliminary Web search turns up many
instances of this problem. My understanding is that these phones
periodically communicate with the network, and during these brief bursts
the carrier is modulated at around 200 Hz resulting is a clear,
repeatable buzz pattern. How is this buzz getting into the PC speaker
amplifier, and, more importantly, how can it be prevented?

Thanks,
Doug


"Verizon" wrote in message
news:fvw3i.3491$kf1.1314@trnddc01...
This is normal. Just keep the phone away from the speakers.

No, this is NOT normal. This is stupidity on the part of whom ever came up
with the GSM standard... Any NORMAL person, business, corporation, etc.,
would have properly tested for interference potential prior to releasing or
even accepting such a standard.

"PowerHouse Communications" wrote in message
...

"Verizon" wrote in message
news:fvw3i.3491$kf1.1314@trnddc01...
This is normal. Just keep the phone away from the speakers.

No, this is NOT normal. This is stupidity on the part of whom ever came
up with the GSM standard... Any NORMAL person, business, corporation,
etc., would have properly tested for interference potential prior to
releasing or even accepting such a standard.

Yes, it is normal. The PC speakers are not bypassed for the RF the phones
generate. They save a few cents by not doing this. There is nothing wrong
with the phones.

I agree, this is normal, and FCC rules say it's the speakers
responsibility/fault to protect themselves from the RF. Not the phones
responsibility for the speakers being unprotected.

-Smile


Ralph Mowery wrote:
"PowerHouse Communications" wrote in message
...

"Verizon" wrote in message
news:fvw3i.3491$kf1.1314@trnddc01...

This is normal. Just keep the phone away from the speakers.

No, this is NOT normal. This is stupidity on the part of whom ever came
up with the GSM standard... Any NORMAL person, business, corporation,
etc., would have properly tested for interference potential prior to
releasing or even accepting such a standard.


Yes, it is normal. The PC speakers are not bypassed for the RF the phones
generate. They save a few cents by not doing this. There is nothing wrong
with the phones.