What Li-Ion might improve on is mAh (read: how long they last before needing to be recharged)
Not quite. mAh specifies the charge, not energy; a battery than can supply 100mA for an hour at 100V has much more energy than the one at 3V. With the above two cells, the Li-Ion stores 4.6kJ, which is more than the NiMH with 3.6kJ.
Double the voltage, with a little less than half the mAh rating of a same size NiMH cell. Therefore, it provides a little less energy capacity. (mAh gives Coulombs, not Joules).
On the plus side, its discharge curve is more abrupt, so it tends to be better for powering electronics. Further, it provides many more charge cycles, has no memory effect, and has great shelf life (won't discharge as quickly as NiMH if not used).
Good point. But it seems like a double-edged sword. If Google, or, even worse, a coalition of Internet companies, refused to pay ISP X, they might drive a lot of X's customers away.
What do you mean, Li-Ion AA[A] are cost prohibitive? They cost $3.59 and $2.99, respectively, on, say, batteryspace.com. And each has more than double the voltage of a NiMH cell.
1. If this puts the bandwidth hogs into a higher price tier, so be it.
2. Will this really allow the telcos to blackmail internet company X? I would imagine, say, Google already pays an enormous amount of money for their multiple OC-3*2^zillion links. Couldn't they go to a different ISP?
3. If this made general Internet access suck it could (here's to hoping) force deregulation of transmission lines.
What happens when I download a file just to find out it's corrupt and have to download it again?
You would pay for it. It's not that big a deal, really. Do you kick yourself when you forget to turn off the lights in the basement overnight? It's still a far cry from running a 20 kW air conditioner.
Truly such a thing would kill the Internet.
It would kill the provider who tried it, thanks to the good old competition. As long as the statistics hold up, the flat-rate model is viable.
I know, but I was thinking more along the lines of filing a small claims suit to the tune of $5k for lost time, dealing with cleanup, reinstalling Windows, etc. (outside of the terms of the class action). Without having actually gotten or used the CD the claim wouldn't be very credible.
Actually, you could. Light exerts a very small force as it bounces (the principle proposed for light sails) so in theory given enough time and precision it could be done.
I had a boss who loved to get dual-CPU systems. Why? "Because that way one CPU can run the web server and one CPU can run the database." No matter how often I tried to shake that view from his head it never left. (In point of fact, both were context switching in and out of both CPUs pretty regularly).
Those are not exactly CPU-hungry applications that could take advantage of multiple CPUs. No scheduler in the world will help run a webserver and database better on that machine if the I/O subsystem is the bottleneck.
Any practical antenna such as a half wave dipole will eventually start to fall off as 1/r^2 in free space in a given direction. Of course, the radiation pattern will not be perfect like on an isotropic radiator.
Anyone interested in antenna radiation patterns should look at the NEC2 family of open source simulators which can deal with quite sophisticated geometries. There is even a windows-only front end, called 4nec2, that dramatically simplifies the usage.
I believe that's also known as an arc welder. How do you think your mp3 player with in-ear headphones would behave in the (very common) dead-short failure mode?
Probably nothing too spectacular, maybe smoke a little bit and melt down. I use.1mm wire across a few volts power supply all the time, it's great for cutting styrofoam.
ahh.. the magic of a good HF multi-band vertical.. maybe not so much magic, but lots of coils:)
Don't I wish... I was trying to put together an impedance matching network for a 802.11a antenna, figuring I'd just get some coils from Digikey. Unfortunately 1nH is way out of their ballpark:)
Finally bandwidth to compete with a stationwagon loaded with backup tapes.
Hah, the problem is that I can put one of your universal radios on the van, get close to the sender, load up, drive to receiver, and unload. For a big enough distance with a large near/far radio capacity ratio the van always wins:)
Antennas only affect the shape of the RF output, and the frequency range at which you can efficiently radiate.
I wouldn't call that "only..." it's actually a big problem for UWB radios, where antennas need to be especially wideband.
Most of what software defined radios is talking about modulation changes, not frequncy changes.
I think that's because changing frequencies is really not hard; either you sample the whole spectrum and do everything in software, or switch between front ends. (I love to see a gigasample per second ADC, that would be a thing to behold!)
Omni-directional wifi antennas on most APs: a single stick with a fraction of the wavelength of 2.4ghz.
Yes, if by fraction you mean one quarter or half wavelengths. Lambda for 2.4GHz is about 12cm, not that much.
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I'm pretty sure all AAA, AA, C, and D batteries provide roughly the same voltage.
No. Their AAA cell provides 3.7V (that's the Li-Ion cell voltage dictated by physics) and 350 mAh. Compare this to a 1.2V NiMH cell with 850mAh.
Li-Ion cells
NiMH cells
What Li-Ion might improve on is mAh (read: how long they last before needing to be recharged)
Not quite. mAh specifies the charge, not energy; a battery than can supply 100mA for an hour at 100V has much more energy than the one at 3V. With the above two cells, the Li-Ion stores 4.6kJ, which is more than the NiMH with 3.6kJ.
Double the voltage, with a little less than half the mAh rating of a same size NiMH cell. Therefore, it provides a little less energy capacity. (mAh gives Coulombs, not Joules).
On the plus side, its discharge curve is more abrupt, so it tends to be better for powering electronics. Further, it provides many more charge cycles, has no memory effect, and has great shelf life (won't discharge as quickly as NiMH if not used).
Good point. But it seems like a double-edged sword. If Google, or, even worse, a coalition of Internet companies, refused to pay ISP X, they might drive a lot of X's customers away.
Maybe you could build in a small diesel-powered generator and use that to recharge the car.
What do you mean, Li-Ion AA[A] are cost prohibitive? They cost $3.59 and $2.99, respectively, on, say, batteryspace.com. And each has more than double the voltage of a NiMH cell.
1. If this puts the bandwidth hogs into a higher price tier, so be it.
2. Will this really allow the telcos to blackmail internet company X? I would imagine, say, Google already pays an enormous amount of money for their multiple OC-3*2^zillion links. Couldn't they go to a different ISP?
3. If this made general Internet access suck it could (here's to hoping) force deregulation of transmission lines.
What happens when I download a file just to find out it's corrupt and have to download it again?
You would pay for it. It's not that big a deal, really. Do you kick yourself when you forget to turn off the lights in the basement overnight? It's still a far cry from running a 20 kW air conditioner.
Truly such a thing would kill the Internet.
It would kill the provider who tried it, thanks to the good old competition. As long as the statistics hold up, the flat-rate model is viable.
Joel Spolsky, famous for his essays about the software industry, also founded a source control business. What is going on here :)
I know, but I was thinking more along the lines of filing a small claims suit to the tune of $5k for lost time, dealing with cleanup, reinstalling Windows, etc. (outside of the terms of the class action). Without having actually gotten or used the CD the claim wouldn't be very credible.
Man, I wish I bought their rootkitted CD :)
After all, AMD typically performs better when it runs at a smaller clock speed. :^)
they are able to provide "lifetime cancer protection"
:)
I see, so the protection lasts right until they die... from cancer. I think Aleve can do this just as well
Actually, you could. Light exerts a very small force as it bounces (the principle proposed for light sails) so in theory given enough time and precision it could be done.
That doesn't always work. For example, my girlfriend can't get enough of Heroes of Might and Magic 3, I barely get time for anything else!
Anyone know any other good games with hot-seat type of play?
He didn't say they are the same, he said that there should be no legal distinction.
I had a boss who loved to get dual-CPU systems. Why? "Because that way one CPU can run the web server and one CPU can run the database." No matter how often I tried to shake that view from his head it never left. (In point of fact, both were context switching in and out of both CPUs pretty regularly).
Those are not exactly CPU-hungry applications that could take advantage of multiple CPUs. No scheduler in the world will help run a webserver and database better on that machine if the I/O subsystem is the bottleneck.
http://www.kinderstart.com:8080/kindertoday/114264 8153
The funny thing is, it looks like they are using slash!
They will be writing computer simulations of spores!
He's asking *how* to move away. He came to the right place.
Any practical antenna such as a half wave dipole will eventually start to fall off as 1/r^2 in free space in a given direction. Of course, the radiation pattern will not be perfect like on an isotropic radiator.
Anyone interested in antenna radiation patterns should look at the NEC2 family of open source simulators which can deal with quite sophisticated geometries. There is even a windows-only front end, called 4nec2, that dramatically simplifies the usage.
I believe that's also known as an arc welder. How do you think your mp3 player with in-ear headphones would behave in the (very common) dead-short failure mode?
.1mm wire across a few volts power supply all the time, it's great for cutting styrofoam.
Probably nothing too spectacular, maybe smoke a little bit and melt down. I use
RAIP: Redundant Array of Inexpensive Platters
ahh.. the magic of a good HF multi-band vertical.. maybe not so much magic, but lots of coils :)
:)
Don't I wish... I was trying to put together an impedance matching network for a 802.11a antenna, figuring I'd just get some coils from Digikey. Unfortunately 1nH is way out of their ballpark
Finally bandwidth to compete with a stationwagon loaded with backup tapes.
:)
Hah, the problem is that I can put one of your universal radios on the van, get close to the sender, load up, drive to receiver, and unload. For a big enough distance with a large near/far radio capacity ratio the van always wins
Antennas only affect the shape of the RF output, and the frequency range at which you can efficiently radiate.
I wouldn't call that "only..." it's actually a big problem for UWB radios, where antennas need to be especially wideband.
Most of what software defined radios is talking about modulation changes, not frequncy changes.
I think that's because changing frequencies is really not hard; either you sample the whole spectrum and do everything in software, or switch between front ends. (I love to see a gigasample per second ADC, that would be a thing to behold!)
Omni-directional wifi antennas on most APs: a single stick with a fraction of the wavelength of 2.4ghz.
Yes, if by fraction you mean one quarter or half wavelengths. Lambda for 2.4GHz is about 12cm, not that much.