Go ahead and write a proposal for telescope time on Keck II for an Apollo landing site observation run. You'd better have some funding from the moon conspiracy theorists in hand to pay for that expensive time, since it's not likely to lead to a paper in the ApJ.
I wondered about that also, but then I realized that these checks are treated as trophies and are presumably posted on the web as scanned images. The check that you or I write to the phone company is never posted on the web, so it's not likely to be scammed from.
Yeah, I though that as well until one day I sent a $14,000 check to my mortgage company and they deposited it for the default payment amount of $1400. The scary part is that the bank didn't read the check at all, using the mortgage company's data tape instead of the actual document to learn the deposit amount. Seems they are not willing to take the time to read the numbers written on their checks! Momentum is the only thing sustaining the banking industry.
This is all addressed in the article. Part 15 has nothing to do with the behavior of the cellphone itself - it's governed by Part 22. The phone is doing its job properly, but the authors of Part 15 did a cop-out to allow the production of $10 clock radios. You'd have to spend $12 on a clock radio for it to be well made enough to not emit the GSM buzz.
They don't want the chips to get hotter than they already do. They want them to work correctly when they are run hotter. This allows them to use passive cooling in more climates, which saves big bucks on the cooling bill.
I used to think that until I started to work for astronomers. They actually take photos of noise, and then add noisy images together ("stacking") until pictures of interesting faraway things emerge from the noise. That's why a nightly sky survey is so useful - you can add together a few months of images and see stuff that you would never have seen in a single image.
I work on helium-cooled radio telescope receivers. They have trouble regularly - it sometimes takes five or six tries to get the thing cooling properly. These poor folks have over a thousand giant Dewars to keep cold! Give them a break.
In the radio astronomy world, the picture is most often a graph. Once in a while, we make low-resolution false-color pictures, created by scanning the antenna over the sky region in a raster pattern. Very tedious work.
If you read the article, you'll see a graph with wiggly lines representing the interference fringes. This is as close as you'll get to a picture, and believe me, when an astronomer sees a graph with the right wiggles, they get very excited!
The LSST is a ground-based telescope, so the mount can be adjusted if it's not in the right place. Besides, the engineers are, shall we say, "sensitized" to this particular error for some reason.
The paper filler was useful in some cases - it kept the record from falling apart, so it would still play (albeit extra-noisily) if cracked.
There was a spectrum of record pressing quality back then, too. I have some Billy Holiday records on Columbia that are nearly unplayable due to surface noise, yet many other records sound very clean.
Some later 78s were pressed with vinyl, such as Elvis stuff. It sounds very good.
That's one reason it gets such good battery life. It uses the magic of diffraction gratings to use nearly all the light that it receives.
I read that the creator of the screen is in the process of commercializing it, and I can't wait for it to get into the world of readily-available products.
The elevators in my office were built in the late 1970s using relay logic. Our radiotelescope, on the other hand, runs some FORTRAN code left over from the PDP-11 days.
Don't worry, the signal won't get far enough to be "pir8" with that optimally-bad FM broadcast antenna placement. It should be placed on top of the WiFi high-gain antenna when pir8ing. Then it would have a range greater than the radius of the bike and not blow out the WiFi receiver's front end when turned on. (I'm assuming you turn off WiFi when transmitting,since an FM broadcast signal emitted from right there will wipe out any chance of receiving anything else.)
Yes, that would have been nicer. In a hallway in the Steward Observatory office building, there was once a poster illustrating the proposed Super Huge Interferometric Telescope I think the poster was done by bored grad students.
I've been in the LBT a couple times. It's B-I-G! And it's on top of Mt. Graham, for which I have a red squirrel permit issued by USFS to visit the site for work purposes only. I don't know what telescope you're thinking of.
The point isn't that he's closing the magnetic circuit, it's that he closes it with an alternating field that alternates 4 times faster than the rotor's inherent frequency. Feeding a higher-frequency signal into the motor will make it want to accelerate, no?
I think you're missing an important part of the puzzle.
When I watched the video, I was struck by how the coil on the right doesn't have a pole piece on its far end to take the magnetic flux back to the permanent magnet wheel. Then I saw him demonstrate the difference between having a brass motor shaft and a steel shaft, and I had an inkling of what was going on.
An induction motor is a very complex device whose complexity is masked by its physical simplicity. The induction motor builds a rotating magnetic field in the rotor by inducing current flow into the aluminum rotor windings from the AC stator coil (as any power transformer does). The interaction between the induced field and the stator field causes the motor to turn. The rotor has specific requirements with regard to the shape of the windings to achieve maximum efficiency. Understanding the current flow and the magnetic flux is a job for theoretical experts (which I'm not).
Notice that the apparatus is mounted on a steel table. This provides a flux path from the motor housing to the black coil at the right end of the machine. The addition of his steel shaft has "completed the magnetic circuit" between this coil (an AC generator) and the induction motor rotor, which will do very interesting things to the magnetic field on the rotor! Especially since the field he generates is an AC field with what, 16 poles? I think he has a four pole 1750 RPM induction motor.
As you point out, prosthetics can be designed with any parameters you like. The manufacturer of the Cheetah feet could design an Olympic-qualified model that gives just as much spring as a real foot and no more.
The question is whether the IAAF would be interested in permitting such a device to be used at all. If it were an American group instead of international, the Americans with Disabilities Act would have something to say about that.
Slashdot Mirror
You'd only need a megawatt or so to get 100kW of laser power out the spigot. You can get a megawatt form Caterpillar Power in a 30 foot semi-trailer.
Go ahead and write a proposal for telescope time on Keck II for an Apollo landing site observation run. You'd better have some funding from the moon conspiracy theorists in hand to pay for that expensive time, since it's not likely to lead to a paper in the ApJ.
Try crunching those numbers by income instead of skin color and see what comes out.
Yeah... my wife Terry would agree with that sentiment.
I wondered about that also, but then I realized that these checks are treated as trophies and are presumably posted on the web as scanned images. The check that you or I write to the phone company is never posted on the web, so it's not likely to be scammed from.
Yeah, I though that as well until one day I sent a $14,000 check to my mortgage company and they deposited it for the default payment amount of $1400. The scary part is that the bank didn't read the check at all, using the mortgage company's data tape instead of the actual document to learn the deposit amount. Seems they are not willing to take the time to read the numbers written on their checks! Momentum is the only thing sustaining the banking industry.
This is all addressed in the article. Part 15 has nothing to do with the behavior of the cellphone itself - it's governed by Part 22. The phone is doing its job properly, but the authors of Part 15 did a cop-out to allow the production of $10 clock radios. You'd have to spend $12 on a clock radio for it to be well made enough to not emit the GSM buzz.
They don't want the chips to get hotter than they already do. They want them to work correctly when they are run hotter. This allows them to use passive cooling in more climates, which saves big bucks on the cooling bill.
I used to think that until I started to work for astronomers. They actually take photos of noise, and then add noisy images together ("stacking") until pictures of interesting faraway things emerge from the noise. That's why a nightly sky survey is so useful - you can add together a few months of images and see stuff that you would never have seen in a single image.
...as the Internet (and even ARPANET) didn't exist in 1958, as you may have guessed.
I work on helium-cooled radio telescope receivers. They have trouble regularly - it sometimes takes five or six tries to get the thing cooling properly. These poor folks have over a thousand giant Dewars to keep cold! Give them a break.
In the radio astronomy world, the picture is most often a graph. Once in a while, we make low-resolution false-color pictures, created by scanning the antenna over the sky region in a raster pattern. Very tedious work. If you read the article, you'll see a graph with wiggly lines representing the interference fringes. This is as close as you'll get to a picture, and believe me, when an astronomer sees a graph with the right wiggles, they get very excited!
Roger Angel likes to make mirrors this way. If they wanted to use a segmented mirror, then it wouldn't be cast in Tucson.
The LSST is a ground-based telescope, so the mount can be adjusted if it's not in the right place. Besides, the engineers are, shall we say, "sensitized" to this particular error for some reason.
The paper filler was useful in some cases - it kept the record from falling apart, so it would still play (albeit extra-noisily) if cracked.
There was a spectrum of record pressing quality back then, too. I have some Billy Holiday records on Columbia that are nearly unplayable due to surface noise, yet many other records sound very clean.
Some later 78s were pressed with vinyl, such as Elvis stuff. It sounds very good.
That's one reason it gets such good battery life. It uses the magic of diffraction gratings to use nearly all the light that it receives. I read that the creator of the screen is in the process of commercializing it, and I can't wait for it to get into the world of readily-available products.
I keep one of these in my wallet. It's wafer-thin. Pretty much the size of a flash chip plus a USB connector wafer. They come in sizes up to 8GB.
The elevators in my office were built in the late 1970s using relay logic. Our radiotelescope, on the other hand, runs some FORTRAN code left over from the PDP-11 days.
Don't worry, the signal won't get far enough to be "pir8" with that optimally-bad FM broadcast antenna placement. It should be placed on top of the WiFi high-gain antenna when pir8ing. Then it would have a range greater than the radius of the bike and not blow out the WiFi receiver's front end when turned on. (I'm assuming you turn off WiFi when transmitting,since an FM broadcast signal emitted from right there will wipe out any chance of receiving anything else.)
Yes, that would have been nicer. In a hallway in the Steward Observatory office building, there was once a poster illustrating the proposed Super Huge Interferometric Telescope I think the poster was done by bored grad students.
I've been in the LBT a couple times. It's B-I-G! And it's on top of Mt. Graham, for which I have a red squirrel permit issued by USFS to visit the site for work purposes only. I don't know what telescope you're thinking of.
The point isn't that he's closing the magnetic circuit, it's that he closes it with an alternating field that alternates 4 times faster than the rotor's inherent frequency. Feeding a higher-frequency signal into the motor will make it want to accelerate, no?
I think you're missing an important part of the puzzle.
When I watched the video, I was struck by how the coil on the right doesn't have a pole piece on its far end to take the magnetic flux back to the permanent magnet wheel. Then I saw him demonstrate the difference between having a brass motor shaft and a steel shaft, and I had an inkling of what was going on.
An induction motor is a very complex device whose complexity is masked by its physical simplicity. The induction motor builds a rotating magnetic field in the rotor by inducing current flow into the aluminum rotor windings from the AC stator coil (as any power transformer does). The interaction between the induced field and the stator field causes the motor to turn. The rotor has specific requirements with regard to the shape of the windings to achieve maximum efficiency. Understanding the current flow and the magnetic flux is a job for theoretical experts (which I'm not).
Notice that the apparatus is mounted on a steel table. This provides a flux path from the motor housing to the black coil at the right end of the machine. The addition of his steel shaft has "completed the magnetic circuit" between this coil (an AC generator) and the induction motor rotor, which will do very interesting things to the magnetic field on the rotor! Especially since the field he generates is an AC field with what, 16 poles? I think he has a four pole 1750 RPM induction motor.
that anyone had any doubt that the RIAA were anything but money-grubbing middlemen.
The question is whether the IAAF would be interested in permitting such a device to be used at all. If it were an American group instead of international, the Americans with Disabilities Act would have something to say about that.