luke.leighton <luke.leighton <at> gmail.com> writes:
funny that....
What do you mean, my car's cell-phone system is only designed to last 2 years, and that was designed 5 years ago when the car was in design? And car companies are more interested in charging $1000 for a $100 dollar part since you can't get it "factory-finish" on the aftermarket.
Course, you could also have a car that runs on a generator (7kW) and seats 2 with some funky styling (for airflow reasons) and the "entertainment" and nav system is run from a pc card. Now if only I could remember who I knew that was working on that...
On Thu, Oct 24, 2013 at 3:14 PM, Derek dlahouss@mtu.edu wrote:
luke.leighton <luke.leighton <at> gmail.com> writes:
funny that....
What do you mean, my car's cell-phone system is only designed to last 2 years, and that was designed 5 years ago when the car was in design? And car companies are more interested in charging $1000 for a $100 dollar part since you can't get it "factory-finish" on the aftermarket.
you heard about why if you push a button a garage-door opener it will set car alarms off in the neighbourhood? it's because they use a $0.15 part @ 433mhz with a wide-band reception instead of a $1 part with proper narrow-band filtering. i assume that this is also the reason why, if you are locked out of your car, you can ask someone with a GSM mobile phone to press a duplicate door-opener AT THEIR END of the conversation...
Course, you could also have a car that runs on a generator (7kW) and seats 2 with some funky styling (for airflow reasons) and the "entertainment" and nav system is run from a pc card. Now if only I could remember who I knew that was working on that...
ha ha very funny derek :) actually the original design seated 3 (one staggered in the middle) and the new one seats 4. i'll get to that again after this is all underway....
l.
luke.leighton <luke.leighton <at> gmail.com> writes:
it's because they use a $0.15 part <at> 433mhz with a wide-band reception instead of a $1 part with proper narrow-band filtering. i assume that this is also the reason why, if you are locked out of your car, you can ask someone with a GSM mobile phone to press a duplicate door-opener AT THEIR END of the conversation...
Luke, you said this with too straight a face. Maybe you're just taking the piss, but GSM uses a voice codec with between 3k and 12k of bandwidth. If it's not an audible part of speech, the codec should drop it to the floor.
So, in Britain, are car-door openers audible?
On Thu, Oct 24, 2013 at 3:50 PM, Derek dlahouss@mtu.edu wrote:
luke.leighton <luke.leighton <at> gmail.com> writes:
it's because they use a $0.15 part <at> 433mhz with a wide-band reception instead of a $1 part with proper narrow-band filtering. i assume that this is also the reason why, if you are locked out of your car, you can ask someone with a GSM mobile phone to press a duplicate door-opener AT THEIR END of the conversation...
Luke, you said this with too straight a face. Maybe you're just taking the piss,
i'm not - it was however an apocryphal story. good one, too :)
but GSM uses a voice codec with between 3k and 12k of bandwidth. If it's not an audible part of speech, the codec should drop it to the floor.
my guess is that what's going on is that R.F.-level interference between the transmitters is resulting in a transmission that the broad-band car receiver ICs are capable of picking up, and that yes, the modulation rate is within the bandwidth of GSM codecs. if ever you've stood next to a stereo with a GSM phone and got "b-bp, b-bp, bzzzzz" when someone speaks, you'll have a ... ok you get the idea
anyway back to it... :)
l.
On 10/24/2013 10:14 AM, Derek wrote:
luke.leighton <luke.leighton <at> gmail.com> writes:
funny that....
What do you mean, my car's cell-phone system is only designed to last 2 years, and that was designed 5 years ago when the car was in design? And car companies are more interested in charging $1000 for a $100 dollar part since you can't get it "factory-finish" on the aftermarket.
We've mused on this subject before. "To the ARCHIVES!" *NaNaNaNaNaNa...*
http://lists.phcomp.co.uk/pipermail/arm-netbook/2013-May/007564.html
arm-netbook@lists.phcomp.co.uk
-
Derek -
luke.leighton -
Scott Sullivan