important information on how to kill a Roomba if you get trapped in a sci-fi horror flick with one threatening to suck up your breakfast.
I'll remember that, next time that happens. Though, if it's a typical sci-fi/horror flick, my breakfast would be trying to eat me anyway.
The best way to kill one, though, would be to make a little trail of dirt that it follows around a corner, where you are waiting with a sledgehammer....
Nice hack, but it can be done for much less money.
BG Micro sells Motorola OnCore GPS boards for about $20. They also have just the pigtail connector for a serial port, but who's complaining?
The single-board computer is nice, but you can find similar (and better) boards for much, much less than $200. Simply graze eBay for a few weeks, get a feel for what's there. I recently picked up a single-board for $40, comes with everything including four serial ports, and still retails for about $500. Same board that John uses in the Armadillo project.
And using Basic Stamps...well, let's just say I never liked the idea of paying $50 to $90 for the exact part I could buy from Microchip for a couple bucks. Nor the idea of writing slow code in Basic, as opposed to tasty assembler and absolute hardware control.
The chase description was great though; trucking down the freeway trying to log into a balloon that's well over any airline traffic, hoping it doesn't land in someone's windshield...or swimming pool. Makes the model rocket hunts of my youth seem pretty tame, even the time we found the rocket neatly draped on the front doormat of the mean neighbor lady's house....
Well...of course it does. Kind of neat how that works, eh? Totally undocumented.
Instruction manuals all say to use two strokes for "x". Most of us figured out that Graffiti was a one-stroke alphabet anyway (the "x" really stuck out too much), but apparently the ruse didn't work this time.
One could craft a mini-conspiracy theory about the choice of the letter "x".
Since a BIOS is only part of a motherboard: what steps will hardware vendors have to take, in order to incorporate your BIOS? Will they have to adhere to certain hardware design rules or controls in order to maintain the TCPA? Is there going to be a licensing procedure for hardware manufacturers?
Wasn't Harvey Mudd started by some individuals from Rose-Hulman? Mudd was on my short list, but I ended up going to Rose.
Not that it's helped: managed to graduate after four years in 2002 and still looking. Nobody I've talked to believes the projects I've done were more important than a 4.0 GPA, or thinks I'm worth four times my weight in silver. Probably closer to low-grade steel, or plastic.
Someday I may be slashdotted, and my provider is probably not going to withstand it (I have shell access, and can see that my site is hosted on a Cobalt with about 150 other sites).
The slashdot FAQ's excuse "well, do you want to wait six hours for a cool breaking story while we ask permission?" is just ludicrous. This guy's site was obviously going to be there for a long time, it wasn't a breaking-news item by any stretch of the imagination. In fact, most sites that end up Slashdotted are just this type. The major breaking news stories are all hosted on servers that should be able to take a Slashdotting. The "look what I did in my garage" stories are not time-sensitive and just aren't set up for crushing traffic.
I've noticed an overall sense of degeneration on slashdot for quite a while. No one's complaints are ever taken into consideration: there is a problem with repeat posts. Most of us recognize a repost within seconds of reading it. Either the editors have sub-average memory retention, or they don't read slashdot. And what's with Cliff? Nothing happens on Ask for a week, then suddenly there are 20 stories, all of them complete crap.
I seriously have been surfing slashdot less. I find that I get more interesting news and articles on Google. The only thing that keeps me around slashdot is the community. And if enough of us get tired of having complaints and obvious solutions go unanswered, there won't be a community either.
You're obviously not a BSEE, or any type of engineer for that matter. I'm not even sure you're an adult.
This may surprise you, but calculus (specifically integration) is not the end of mathematics. The Nyquist theorem states that in order to accurately reproduce a frequency, the sample rate must be twice or more than the frequency. Using just two samples per waveform, the sine wave can be reconstructed.
And if you remember Fourier transforms, you'll realize that any waveform can be broken down into component sine waves. With enough samples, the original waveform can be reconstructed with practically no measurable difference from the analog source. And, yes, with today's technology, quite possible and commonly done.
No, the digitally-reproduced waveform is not going to be 100% the same. It will be something like 99.999%. And I'd like to see you get that with an analog signal, taking into account the capacitance and inductance effects of the transmission line, thermal noise from resistances, and analog processing done with parts that commonly are 10% away from specified value.
I'm not worried about what your opinion is of my competence. Any other electrical engineer knows what I just told you.
We're talking about cell phones, not pure sound. And many of us have taken signal processing and data transmission classes.
Digital sound does not suffer from signal degradation. Hold true for communications, CD/vinyl, whatever. You only need two samples per cycle to accurately reproduce a sine wave...once enough samples are taken, the output sound will become identical to the analog waveform for all practical purposes. You don't have to go much higher than CD quality to fool the audiophiles; the CD sample rate was a compromise between widely acceptable quality and the cost of manufacture.
Yeah, peri pumps are great. We have hundreds of impeller pumps to recirculate ink on our presses, and the are always dying, going off balance, or developing other problems. Plus, they have to be meticulously cleaned with every ink color change. We're moving to peri pumps exclusively in the next few months...just rinse out or throw away the tube, snap in, and go.
Assuming the magnetron and cell phone have identical spherical radiation patterns, the energy from the magnetron would be about seven times more than the cell phone.
Additionally, the magnetron will penetrate much deeper: 5mm deep into your skull, the cell phone's power will be 400% less, and the magnetron's power will be 15% less. That assumes zero blocking effects from the tissue.
Considering I recently paid about $25 each for unscreened, unmasked boards from ExpressPCB, and that was a "buy three tiny boards for one low price" deal.
Olimex's site is pretty crappy, but the guy'd board doesn't look too bad. That $26 board is 6"x4" and my other boards were limited to 3.8" x 2.5".
From my experience, the people running the school paper websites are doing it because they want the experience. What looks better on a resume: "Developed custom applications for automatic formatting and publishing a news website" or "Found free software to do my job so I could play more Everquest"?
Right now, I'm interested in the construction. I have a project going right now that uses a lot of surface-mount parts (robotic pan-tilt webcam mount, with a Motorola USB microcontroller and integrated USB hub). I had a few boards made, but the tough part is getting those flat-pack devices soldered down. No access to hot-air soldering equipment, so I do it with a fine-tip soldering iron (which is way too big) and a magnifier. I've heard rumors of solder paste and toaster ovens.
Unless he has access to hot-air soldering equipment, the construction cost was probably a bit more than $100. Especially with that etched, drilled, plated, silk-screened, and solder-masked circuit board.
Soldering these things really slows me down, I want to have this project done so I can show it off at interviews, and control/view it through my cell phone.
No, the RFID tags are much less complicated than the ankle bracelet.
There are several problems, though. A detector must be placed at every possible exit point, rather than a radius-based system. Also, the RFID tag has no way of triggering an alert if it is tampered with.
Maybe guarding one or two entrances is ok, until the child figures out how to climb out of a window. The ankle bracelet system works well for actual house arrest cases; they don't use RFID tags.
RF is also too easy to defeat: tinfoil. My RF passcard for work used to set off store alarms, until one of the stores gave me a "Schlage Shield" (piece of tinfoil covered in paper). The autistic child may not actually think of wrapping their RFID bracelet in tinfoil to get past the alarm, but this could happen accidentally; foil-lined potato chip bags, or anything metallic like a watch or pie plate could shield the RF tag. An active bracelet would trigger if communication is interrupted.
I agree completely, you can't just lock the kid inside the house.
Imagine the huge risk you face, if the rest of your family has to use keys, or pass biometric testing, to exit the house.
If there is an emergency and the system works, the autistic kid won't be able to get out. If he was following you, and the door shut behind you and was locked from the outside, that's a huge problem.
If the system failed, no one can get out. At the very least, you have delayed your exit while you break a window, each family member crawls out, etc.,.
All I can see working here is a "house arrest" type of solution. An ankle bracelet will sound an alarm if the wearer wanders too far away, or if the bracelet is tampered with. Commercial solutions exist, obviously. They do usually call the police department in an alarm situation; the best solution would involve some kind of pager your wife would wear. If a ready-made solution is not available, a local consulting engineer may be able to provide a one-off solution for a reasonable (considering the risk) price. You may even be able to find a senior project group at a nearby engineering school, who may be able to get funding in other ways (grants, Lemelson funding).
Wall. Fixable with a $2.00 can of spackle and a dab of paint, but still, it's a bad idea. A nice accumulation of mold will begin to cost quite a bit. And I'd lose my $500 computer to overheating.
So he made up this little kit, invested in some bandwidth (notice the servers are just fine?) and submitted as AC.
Disgusting. And stupid. And an example of what happens when geeks rush in where engineers fear to tread. He might as well produce a water-cooling kit that runs water from a faucet adapter, through a heatsink, and then into the wall. Hey, we have a limitless untapped void in there, right?
Only if you believe the premise behind Dexter's Laboratory.
Re:Chemistry is fun-damental
on
Uncle Tungsten
·
· Score: 3, Funny
And *I* disagree with all of you. Obviously it is the study of electricity that forms the base of all scientific progress.
I can't prove why this is so, but had to get my two cents in for the EE's, even though we aren't pure science. Leave that to the nuclear physicists (*hint hint*).
Slashdot Mirror
important information on how to kill a Roomba if you get trapped in a sci-fi horror flick with one threatening to suck up your breakfast.
I'll remember that, next time that happens. Though, if it's a typical sci-fi/horror flick, my breakfast would be trying to eat me anyway.
The best way to kill one, though, would be to make a little trail of dirt that it follows around a corner, where you are waiting with a sledgehammer....
Oops! Yeah, bgmicro is sold out.
Crap, I was going to get a couple. Guess I should have learned by now, to move fast on surplus.
Anyway, eBay has a few of them. Looks like one can be found under $45, maybe.
Crap.
Nice hack, but it can be done for much less money.
BG Micro sells Motorola OnCore GPS boards for about $20. They also have just the pigtail connector for a serial port, but who's complaining?
The single-board computer is nice, but you can find similar (and better) boards for much, much less than $200. Simply graze eBay for a few weeks, get a feel for what's there. I recently picked up a single-board for $40, comes with everything including four serial ports, and still retails for about $500. Same board that John uses in the Armadillo project.
And using Basic Stamps...well, let's just say I never liked the idea of paying $50 to $90 for the exact part I could buy from Microchip for a couple bucks. Nor the idea of writing slow code in Basic, as opposed to tasty assembler and absolute hardware control.
The chase description was great though; trucking down the freeway trying to log into a balloon that's well over any airline traffic, hoping it doesn't land in someone's windshield...or swimming pool. Makes the model rocket hunts of my youth seem pretty tame, even the time we found the rocket neatly draped on the front doormat of the mean neighbor lady's house....
"v-paper" eh?
I suggest the brand name 'Vaper'.
Well...of course it does. Kind of neat how that works, eh? Totally undocumented.
Instruction manuals all say to use two strokes for "x". Most of us figured out that Graffiti was a one-stroke alphabet anyway (the "x" really stuck out too much), but apparently the ruse didn't work this time.
One could craft a mini-conspiracy theory about the choice of the letter "x".
Supposedly, Jot uses two strokes for some of the letters, and therefore escapes patent infringement.
I just grabbed my Visor and wrote "x". Two strokes.
Since a BIOS is only part of a motherboard: what steps will hardware vendors have to take, in order to incorporate your BIOS? Will they have to adhere to certain hardware design rules or controls in order to maintain the TCPA? Is there going to be a licensing procedure for hardware manufacturers?
Wasn't Harvey Mudd started by some individuals from Rose-Hulman? Mudd was on my short list, but I ended up going to Rose.
Not that it's helped: managed to graduate after four years in 2002 and still looking. Nobody I've talked to believes the projects I've done were more important than a 4.0 GPA, or thinks I'm worth four times my weight in silver. Probably closer to low-grade steel, or plastic.
Right.
Someday I may be slashdotted, and my provider is probably not going to withstand it (I have shell access, and can see that my site is hosted on a Cobalt with about 150 other sites).
The slashdot FAQ's excuse "well, do you want to wait six hours for a cool breaking story while we ask permission?" is just ludicrous. This guy's site was obviously going to be there for a long time, it wasn't a breaking-news item by any stretch of the imagination. In fact, most sites that end up Slashdotted are just this type. The major breaking news stories are all hosted on servers that should be able to take a Slashdotting. The "look what I did in my garage" stories are not time-sensitive and just aren't set up for crushing traffic.
I've noticed an overall sense of degeneration on slashdot for quite a while. No one's complaints are ever taken into consideration: there is a problem with repeat posts. Most of us recognize a repost within seconds of reading it. Either the editors have sub-average memory retention, or they don't read slashdot. And what's with Cliff? Nothing happens on Ask for a week, then suddenly there are 20 stories, all of them complete crap.
I seriously have been surfing slashdot less. I find that I get more interesting news and articles on Google. The only thing that keeps me around slashdot is the community. And if enough of us get tired of having complaints and obvious solutions go unanswered, there won't be a community either.
You're obviously not a BSEE, or any type of engineer for that matter. I'm not even sure you're an adult.
This may surprise you, but calculus (specifically integration) is not the end of mathematics. The Nyquist theorem states that in order to accurately reproduce a frequency, the sample rate must be twice or more than the frequency. Using just two samples per waveform, the sine wave can be reconstructed.
And if you remember Fourier transforms, you'll realize that any waveform can be broken down into component sine waves. With enough samples, the original waveform can be reconstructed with practically no measurable difference from the analog source. And, yes, with today's technology, quite possible and commonly done.
No, the digitally-reproduced waveform is not going to be 100% the same. It will be something like 99.999%. And I'd like to see you get that with an analog signal, taking into account the capacitance and inductance effects of the transmission line, thermal noise from resistances, and analog processing done with parts that commonly are 10% away from specified value.
I'm not worried about what your opinion is of my competence. Any other electrical engineer knows what I just told you.
We're talking about cell phones, not pure sound. And many of us have taken signal processing and data transmission classes.
Digital sound does not suffer from signal degradation. Hold true for communications, CD/vinyl, whatever. You only need two samples per cycle to accurately reproduce a sine wave...once enough samples are taken, the output sound will become identical to the analog waveform for all practical purposes. You don't have to go much higher than CD quality to fool the audiophiles; the CD sample rate was a compromise between widely acceptable quality and the cost of manufacture.
Yeah, peri pumps are great. We have hundreds of impeller pumps to recirculate ink on our presses, and the are always dying, going off balance, or developing other problems. Plus, they have to be meticulously cleaned with every ink color change. We're moving to peri pumps exclusively in the next few months...just rinse out or throw away the tube, snap in, and go.
Creative math there.
Assuming the magnetron and cell phone have identical spherical radiation patterns, the energy from the magnetron would be about seven times more than the cell phone.
Additionally, the magnetron will penetrate much deeper: 5mm deep into your skull, the cell phone's power will be 400% less, and the magnetron's power will be 15% less. That assumes zero blocking effects from the tissue.
Paranoia and hearsay does not equal fact.
You can't hear 150KHz.
Not even dogs can.
Ummm...yeah, that is totally insane.
Considering I recently paid about $25 each for unscreened, unmasked boards from ExpressPCB, and that was a "buy three tiny boards for one low price" deal.
Olimex's site is pretty crappy, but the guy'd board doesn't look too bad. That $26 board is 6"x4" and my other boards were limited to 3.8" x 2.5".
Not really.
From my experience, the people running the school paper websites are doing it because they want the experience. What looks better on a resume: "Developed custom applications for automatic formatting and publishing a news website" or "Found free software to do my job so I could play more Everquest"?
Not bad, not bad at all.
HMMMM. I work in a place that prints mass quantities of stuff. Wonder if flexographic or litho plate processes could be adapted to this.
Yes, it's cool, and I'd like to build one.
Right now, I'm interested in the construction. I have a project going right now that uses a lot of surface-mount parts (robotic pan-tilt webcam mount, with a Motorola USB microcontroller and integrated USB hub). I had a few boards made, but the tough part is getting those flat-pack devices soldered down. No access to hot-air soldering equipment, so I do it with a fine-tip soldering iron (which is way too big) and a magnifier. I've heard rumors of solder paste and toaster ovens.
Unless he has access to hot-air soldering equipment, the construction cost was probably a bit more than $100. Especially with that etched, drilled, plated, silk-screened, and solder-masked circuit board.
Soldering these things really slows me down, I want to have this project done so I can show it off at interviews, and control/view it through my cell phone.
within in inch of two of the correct height, which would be near impossible to do.
In other words, very possible to do.
No, the RFID tags are much less complicated than the ankle bracelet.
There are several problems, though. A detector must be placed at every possible exit point, rather than a radius-based system. Also, the RFID tag has no way of triggering an alert if it is tampered with.
Maybe guarding one or two entrances is ok, until the child figures out how to climb out of a window. The ankle bracelet system works well for actual house arrest cases; they don't use RFID tags.
RF is also too easy to defeat: tinfoil. My RF passcard for work used to set off store alarms, until one of the stores gave me a "Schlage Shield" (piece of tinfoil covered in paper). The autistic child may not actually think of wrapping their RFID bracelet in tinfoil to get past the alarm, but this could happen accidentally; foil-lined potato chip bags, or anything metallic like a watch or pie plate could shield the RF tag. An active bracelet would trigger if communication is interrupted.
I agree completely, you can't just lock the kid inside the house.
Imagine the huge risk you face, if the rest of your family has to use keys, or pass biometric testing, to exit the house.
If there is an emergency and the system works, the autistic kid won't be able to get out. If he was following you, and the door shut behind you and was locked from the outside, that's a huge problem.
If the system failed, no one can get out. At the very least, you have delayed your exit while you break a window, each family member crawls out, etc.,.
All I can see working here is a "house arrest" type of solution. An ankle bracelet will sound an alarm if the wearer wanders too far away, or if the bracelet is tampered with. Commercial solutions exist, obviously. They do usually call the police department in an alarm situation; the best solution would involve some kind of pager your wife would wear. If a ready-made solution is not available, a local consulting engineer may be able to provide a one-off solution for a reasonable (considering the risk) price. You may even be able to find a senior project group at a nearby engineering school, who may be able to get funding in other ways (grants, Lemelson funding).
Wall. Fixable with a $2.00 can of spackle and a dab of paint, but still, it's a bad idea. A nice accumulation of mold will begin to cost quite a bit. And I'd lose my $500 computer to overheating.
Apparently, someone decided to do two things:
1: Spoof Slashdot
2: Possibly make money due to massive advertising
So he made up this little kit, invested in some bandwidth (notice the servers are just fine?) and submitted as AC.
Disgusting. And stupid. And an example of what happens when geeks rush in where engineers fear to tread. He might as well produce a water-cooling kit that runs water from a faucet adapter, through a heatsink, and then into the wall. Hey, we have a limitless untapped void in there, right?
Only if you believe the premise behind Dexter's Laboratory.
But, where steam come from? Need fire. Fire Good!
And *I* disagree with all of you. Obviously it is the study of electricity that forms the base of all scientific progress.
I can't prove why this is so, but had to get my two cents in for the EE's, even though we aren't pure science. Leave that to the nuclear physicists (*hint hint*).