powerbook making weird sounds when moved
dont get why, but when i move the powerbook. like tilt it forward or something, it makes a weird sound coming from the keyboard, and i muted the speakers so its something internal
the sound .. sounds like a lightsaber kind of
anyone know whta im talkin about? and why?
the sound .. sounds like a lightsaber kind of
anyone know whta im talkin about? and why?
Comments
Between the normal spinning of the Hard Disk and possibly CD/DVD, plus the fan, and even an audible hum from the LCD itself, there are plenty of things to hear normally.
I imagine tilting the hinge both slightly alters the frame as well as airflow, and I assume the fans are the smart type that adjust to tiny differences in both heat and flow.
It can seem radically louder or quieter depending on the environment you are in.
For instance I typically have iTunes playing through my iBook via headphones (which hang in my neck if I'm not using them but i can hear the music a bit) while also having the TV running (usually with XBOX on, even though I might be watching cable) with my AC about 10 feet from me.
You can be sure my iBook is quiet relative to that. But if I take it to a soundproof boardroom while waiting for a client, it sounds like a squadron of TIE bombers.
Originally posted by djmb
havent heard it since today though, coincidently i just got my wireless router today so im using that. but .. could it have anything to do with the aiport being used?
You were going through wired ethernet then? or phone line?
Probably radio interference. That would change when the cable is moved and probably come through the speakers somewhat.
and it happens with speakers muted also
Originally posted by djmb
i was going through ethernet before, but when i unplugged and just watched movies on the couch i never heard this noise
and it happens with speakers muted also
Radio interference happens though long lengths of cable and can cause speakers to hum even if the system has the sound off.
Originally posted by djmb
im completely wireless right now though
The antenna is in the display portion.
Moving an antenna = noise (potentially).
Honestly, johnq had it right. The machines only make noise when we move them about a bunch, and it's even more obvious if there is HDD or CDROM access going on when we move the machine.
Fan noises are normal for machines that have fans to cool them off. That accounts for the normal noise we sense.
johnq correctly stated that the fans, HDDs, and CD spinners are moving at RPMs that make our automobile engines jealous (in the 5 K to 15 K RPM range, depending on device). The angular momentum of the spinners tend to work against the lateral movement of the spinning mass that is caused by your moving the laptop. The little DC electric motors have to work harder to keep the spinners moving at constant velocity, due to conservation of energy. When you move your machine, angular momentum fights the move, and causes the spinners to slightly slow. This causes the speed sensors on the motors to compensate for the slight deceleration by pumping more electrons through the motor's armature windings, helping the motor to keep up. The entire process is usually quite hidden from us. However, the small gap between the read/write heads of your HDD and its magnetic platters is so minute, that when you move your laptop and the read/write heads move laterally in the direction you move your laptop, but the angular momentum of the spinning HDD platters holds the platters from moving with the laptop for a brief moment. If the movement is severe enough, it can cause the read/write heads to scratch the surface of the magnetic media, thus causing bad sectors to start appearing on your HDD.
Okay, maybe the alien idea was a more logical one. I give up.
Karrick