I know one person who owns an HDTV. I'm lead to believe that that is
one more HDTV owner than most people know.
Modern PC's have more than enough CPU power to decode and display
digital video streams from the ethernet. Monitors have more than
enough resolution to display HDTV. 100mbit ethernet is fast
enough for HDTV. We just need cable boxes with ethernet ports.
HDTV could have an order of magnitude more viewers, if the entertainment
industry would get over their computer phobia.
USB is as close as you're going to get.
on
A Universal Power Bus?
·
· Score: 3, Insightful
USB provides 2.5 watts. There are some things out
there that recharge their batteries through the USB
connector already, and it is a much requested feature for the rest. There are a few things out there that use the USB for power, and don't even bother with the data pins.
The parts for a USB interface (with data) are probably still more expensive than a wall-wart type power supply. I think the cheapest wall-warts are around US$1. USB interfaces are 2 or 3 times as much.
If the USB connector is just used for power, then it's the cost of the connector, which is well under $1.
USB prices will continue to drop, so
no other low power bus is likely to be cheaper for the next few years.
If USB becomes more popular, it will probably develope a higher wattage version (or it may have already).
Those photogates have a resolution of 100 microseconds. Any I/O port that can do 10,000 samples a second or better is good enough.
You can measure events that accurately with the gameport, sound card, parallel port or even a serial port.
The photogate has a simple 3 wire digital interface. I betcha that the 3 wires are ground, +5volts and a logic level output. If you can't find the interface documentation on the web, you can use a voltmeter or oscilliscope to figure out the signal.
Here's a way to use the serial port as an accurate timer, even if your OS has terrible latency. Connect a 40 kohm resistor between data out and data in of the serial port. Drive the input of an opto isolator off of your photogate (which is an also opto-isolator, but I like redundancy). Use the opto-isolator to pull data in to +5 through a 1kohm resistor.
So when the opto isolator is off, data will flow through the serial port, when it is on, data won't flow. When the isolator switches, it will corrupt a character. Send an easy to decode series of characters down the serial port, say, 00000001:00000002: etc... Dump the data to a file. See what characters are missing to tell when the isolator is on.
At 115kbaud, each bit is 8.68 microseconds, each character is 86.8 microseconds. So character level timing is good enough, you don't even have to look at the bits of corrupted characters. You can look at those bits for more precision.
Figuring out speeds and accelarations from raw timing data is an excellent project for physics students.
Some data sheets give information on the static sensitivity of some or
all of the contacts on a part. So you can either have an engineer spend
days reviewing all of the data sheets for all the parts you use and plan
to use in the future, or you can buy a humidifier. The humidifier will
cost less.
I've thought similar things, but I didn't find an ISP that sold that sort of service. I needed a couple dozen IP addresses an AUP that allowed resale of services, since I sometimes resold bandwidth and web hosting. I hardly do any commercial stuff now, but I want to keep the option open.
I looked a couple years ago. Since then I moved out of DSL range. I'm stuck in colo mode.
There's not much advantage if any to service via VPN over service via colo. So I'm not willing to pay much of a premium for the service.
Mostly I want it because it would be cool. Getting moderate bandwidth by aggregating a few crappy connections is somewhat cooler than making a Beowolf cluster out of a few crappy systems. My idea of cool is different than most people.
Nope, sorry, that won't work at all. Under the Constitution (for us 'merkins), we are considered innocent until proven guilty. You can't force an innocent person to do any such thing as track down their impersonators.
In the USA,
you can be compelled to testify in a court of law, if the judge decides that your testimony is material to a case. Likewise, the judge can approve search warrants for your property and/or business records.
The trick is crafting the laws such that innocent parties are not unduly burdened, while preventing companies from using commission based sales as a means to avoid anti-spam laws.
I just recieved a spam advertizing DISH Network, it channels people through
redirect.virtumondo.com to www.vmcsatellite.com. I assume that the spammer would get a commission if I signed up through the URL in the spam.
A well crafted law would induce virtumondo.com, VMC Satellite and DISH Network to cooperate in tracking down the spammer. The law should support suing and/or fining non-cooperating businesses.
It's entirely possible that VMC Satellite and DISH Network were framed. If so, they should be happy to help track down the spammer(s).
I live in Michigan, which doesn't have any anti=spam laws yet. It's election time. The state legislature is easy to contact now. What law should I suggest they pass for Michigan?
The 802.11 stuff is pretty darn cheap, and available in rather high bandwidth flavors. Optical won't be cheaper, so its only niches are where 802.11 doesn't work, but optical does, or really high bandwidth, or just because it is cool.
I'll assume you want optical because it is cool.
The lens assemblies are specialized telescopes. You need to focus down to the tip of your fiber. This is a test of your optical skills instead of your electronic skills.
There are a gazillion tradeoffs. Each step creates some optical loss. You can buy bigger lasers, more sensitive receivers, better optics and/or optical amplifiers until the system works.
Tight focus gives long range, but the telescopes will require active tracking.
Looser focus means the telescopes don't have to be precisely aimed.
big mirrors or lenses on your telescopes can produce beams larger than most birds.... and expenses larger than most budgets.
Use "Wavelength Division Multiplexing", WDM, so you can put send and receive on the same fiber and telescopes. If the wavelengths are too far apart, then you can't focus both at the same time. Closer wavelength spacing is pricy. This will eliminate any problems with stray reflections.
Don't use WDM, make sure a receiver doesn't get blinded by its own transmitter. Use four telescopes instead of two. but the pieces are cheaper.
Use carrier grade fiber hardware and get carrier grade bandwidth.
Use stuff you can afford.
Use 802.11, its cheaper and more reliable, just not as cool.
The claimed new part is that the fibers are running through and around the joints of a 3 dimensional structure. It has been done with sheets of triangles. It has been done with bulk materials like steel. The claim is that it hasn't been done before with 3D meshes of fibers which are then cast in resin.
The weight savings is significant where most of the weight being supported is the weight of the support structure itself. Thus the importance for windmills and communication towers.
We won't see this stuff in use until someone figures out how to make it at a reasonable price.
What happens to the throughput when two links are active on one system?
Pretend I have 3 cheap Athlon based systems in one building. Assume one is acting as a server, and the other two are clients that aren't talking to each other.
Because these are the cheaper cards, I only expect 300Mbps when one client is active. What happens when both clients are active?
Ideally, throughput would be no worse than 150Mbps/per card. I suspect it would be much worse.
If multiple cards did work well, then you could buy 6 cards to directly connect 3 machines. Much cheaper than 3 cards and a GigE switch.
I think I'll have to wait until even cheap machines have 64bit/66Mhz PCI busses. I know I'll have to wait until I get all my machines into one building.
I must have missed something, check my numbers. .0005 amps * 1.5 volts * 24 hours/day * 365 days/year is 6.13 watt hours per year.
If your circuit could tolerate voltage droop, a single D-cell would run it for a few years. But voltage droop is probably annoying, so put in a few D-cells and a voltage regulator.
Alkaline batteries aren't rated to last more than 8 years or so, so use lithium batteries if you need something good for decades.
We need to know how many years this should work to give you more precise advise.
I can think of lots of ways to produce 0.75 milliwatts, just none of them will be more reliable than a lithium battery.
Get or make some shelves and/or cabinets too
on
Cable Chaos
·
· Score: 2
Every piece of equipment needs a home. Ideally, it should have ventilation, cable access, allow you to reach all the important openings and controls, and be sturdy.
By sturdy, I mean, that any flat spot larger than a drunken college student's foot, should be strong enough to support a drunken college student. Likewise, any piece of equipment not strong enough to support a drunken college student, should not be exposed.
Only look at the heaviest users on the biggest, fastest machines. Once developers have easy access to faster systems, they will use them much more than the small slow systems. The only developers whose use usage won't go up much, are the ones who already have machines that fast.
See what resources the folks on your fastest systems use, and assume everyone will use that much.
Expect it to ramp up to that usage over the coarse of a few months. Expect the usage to keep going up forever.
are there any potential problems with mounting these drives at an angle
Those drives, no. Some 5 1/4 inch drives needed to be reformatted if you mounted them a different way.
All the 8 inch drives were like that. I've never seen a 14 inch drive mounted anyway but horizontal.
It would be bad.
As the disk drive arms get shorter, the less the angle matters.
I've never heard of a laptop disk crashing because someone turned the laptop on its side.
I want last year's model, but not just any year old model. I want a model that has had a low failure rate.
Where would I find reliability ratings for disks?
Actually, for me, two year old models should be fine. 40 Gbytes is way more than I need for most of my systems. But, I want a new drive, not one that's been sitting on a shelf for 18 months. An old drive probably has some new failure modes, hardening of the lubricants or something.
a shopvac has more than enough power, even if the hose is sucking through the hole of the CDrom.
Actually, too much power, too much noise, too big, and to control it, you need to control a 120V motor.
A wimpy CPU fan doesn't have enough power to hold a CDrom. Much less to pick one up if things aren't in perfect alignment. (This particular CPU fan wasn't powerfull enough to keep my Athlon cool, that's why it was available for experiments.)
So a question for those who know pneumatics:
What is a good cheap, small, relatively quiet fan/blower/pump for a robotic pick and place CD changer?
I think I'll probably take apart a cordless vacuum cleaner and use its blower.
My application is unattended archiving of data to CDroms. 2 copies of each CDrom is enough for me.
One copy of 10 Gbytes of data takes about 15 CDroms. Pretty cheap if there isn't labor involved in swapping the CDs.
Liquid nitrogen has lots of uses around the lab, farm, shop and home. Cooling production computers isn't one of those uses and never was.
Search google for
liquid nitrogen ice cream
for recipes.
Try the string
liquid nitrogen amateur scientist
for experiments you can try at home.
Unless you've got a farm, farm uses aren't interesting. However, if there are farms near by that use it, there may be a liquid nitrogen vendor who delivers to your neighborhood.
Dang, I think I have everything I need to make a
Dean Drive. Some scientist type will ruin my attempt at fame by duplicating my experiment, but with good instruments. Bummer...
A Dean drive generates reactionless force of a special type. To measure this force, we use a special unit, the Bathroom Scale pound. BS pounds are whatever my bathroom scale measures.
My bathroom scale seems to be more sensitive than Dean's. When I stand still on it, I weigh about 195 BS pounds. If I shake my arms at the right speed, my weight drops to 175 BS pounds. That is better than.1 BS G thrust. I suspect a carefully tuned counter-weighted drill motor can do far better.
So when I finally get my device perfected and my paper published, some mean professor is going to explain that measurement equipment may produce incorrect readings in certain situations. That it isn't enough to get the reading you want, you actually have to show you got a valid reading.
For those who want to duplicate my experiments so far, get an aged Health-O-Meter spring scale. Other types of scale have some weird reality field around them that interferes with crack pot physics.
Cool. Fortunately, that's not fast enough to change the conclusion. Even if it really was that fast. The Plextor web page says: capable of burning a CD in just over three minutes.. The back of my envelope says that works out to an average of 25X.
The "burnproof" technology makes it so that nothing catastrophic will happen when the PCI bus bandwidth is saturated.
Seems to me this would be more applicable to VR goggles, or head's up displays.
What a coincidence, those devices seem to make up the rest of Microvision's product line.
Once they figured out how to scan the mirror fast and accurately enough, there are all sorts of uses. Bummer, most of them seem to be out of my price range for at least the next year, probably three.
You can tell it's not ready for primetime, the Spectrum color display system has a two pound piece that mounts on your head, tethered to a 40 pound box. I want one anyway.
Slashdot Mirror
Modern PC's have more than enough CPU power to decode and display digital video streams from the ethernet. Monitors have more than enough resolution to display HDTV. 100mbit ethernet is fast enough for HDTV. We just need cable boxes with ethernet ports.
HDTV could have an order of magnitude more viewers, if the entertainment industry would get over their computer phobia.
The parts for a USB interface (with data) are probably still more expensive than a wall-wart type power supply. I think the cheapest wall-warts are around US$1. USB interfaces are 2 or 3 times as much.
If the USB connector is just used for power, then it's the cost of the connector, which is well under $1.
USB prices will continue to drop, so no other low power bus is likely to be cheaper for the next few years.
If USB becomes more popular, it will probably develope a higher wattage version (or it may have already).
You can measure events that accurately with the gameport, sound card, parallel port or even a serial port.
The photogate has a simple 3 wire digital interface. I betcha that the 3 wires are ground, +5volts and a logic level output. If you can't find the interface documentation on the web, you can use a voltmeter or oscilliscope to figure out the signal.
Here's a way to use the serial port as an accurate timer, even if your OS has terrible latency. Connect a 40 kohm resistor between data out and data in of the serial port. Drive the input of an opto isolator off of your photogate (which is an also opto-isolator, but I like redundancy). Use the opto-isolator to pull data in to +5 through a 1kohm resistor.
So when the opto isolator is off, data will flow through the serial port, when it is on, data won't flow. When the isolator switches, it will corrupt a character. Send an easy to decode series of characters down the serial port, say, 00000001:00000002: etc... Dump the data to a file. See what characters are missing to tell when the isolator is on.
At 115kbaud, each bit is 8.68 microseconds, each character is 86.8 microseconds. So character level timing is good enough, you don't even have to look at the bits of corrupted characters. You can look at those bits for more precision.
Figuring out speeds and accelarations from raw timing data is an excellent project for physics students.
When CDR's became available, it only took a few disks to backup a typical disk. Now it takes 115 to backup a single $83 disk drive.
I looked a couple years ago. Since then I moved out of DSL range. I'm stuck in colo mode.
There's not much advantage if any to service via VPN over service via colo. So I'm not willing to pay much of a premium for the service.
Mostly I want it because it would be cool. Getting moderate bandwidth by aggregating a few crappy connections is somewhat cooler than making a Beowolf cluster out of a few crappy systems. My idea of cool is different than most people.
In the USA, you can be compelled to testify in a court of law, if the judge decides that your testimony is material to a case. Likewise, the judge can approve search warrants for your property and/or business records.
The trick is crafting the laws such that innocent parties are not unduly burdened, while preventing companies from using commission based sales as a means to avoid anti-spam laws.
A well crafted law would induce virtumondo.com, VMC Satellite and DISH Network to cooperate in tracking down the spammer. The law should support suing and/or fining non-cooperating businesses.
It's entirely possible that VMC Satellite and DISH Network were framed. If so, they should be happy to help track down the spammer(s).
I live in Michigan, which doesn't have any anti=spam laws yet. It's election time. The state legislature is easy to contact now. What law should I suggest they pass for Michigan?
I'll assume you want optical because it is cool.
The lens assemblies are specialized telescopes. You need to focus down to the tip of your fiber. This is a test of your optical skills instead of your electronic skills.
There are a gazillion tradeoffs. Each step creates some optical loss. You can buy bigger lasers, more sensitive receivers, better optics and/or optical amplifiers until the system works.
The weight savings is significant where most of the weight being supported is the weight of the support structure itself. Thus the importance for windmills and communication towers.
We won't see this stuff in use until someone figures out how to make it at a reasonable price.
I got Lego's as a tenth anniversary present from my wife.
- Show junior what dad does at work all day.
- Point out that our patent system needs some reforms.
- Provides a lot of advertizing for Dad's business.
I'm not sure what Dad intended at the start, but the last item is surely the most valuable to him now.Pretend I have 3 cheap Athlon based systems in one building. Assume one is acting as a server, and the other two are clients that aren't talking to each other. Because these are the cheaper cards, I only expect 300Mbps when one client is active. What happens when both clients are active?
Ideally, throughput would be no worse than 150Mbps/per card. I suspect it would be much worse.
If multiple cards did work well, then you could buy 6 cards to directly connect 3 machines. Much cheaper than 3 cards and a GigE switch.
I think I'll have to wait until even cheap machines have 64bit/66Mhz PCI busses. I know I'll have to wait until I get all my machines into one building.
So the requirements are something that lights up, is nifty, not too expensive, non-hazardous, and works most of the time.
So something that went dark during periods of unusual calm would be ok.
I doubt anything will outperform a lithium cell in any respect except for being more nifty.
Most of the devices I can think of, will stop working if they get coated with living stuff. How long does stuff stay clean 60 feet down?
If your circuit could tolerate voltage droop, a single D-cell would run it for a few years. But voltage droop is probably annoying, so put in a few D-cells and a voltage regulator.
Alkaline batteries aren't rated to last more than 8 years or so, so use lithium batteries if you need something good for decades.
We need to know how many years this should work to give you more precise advise.
I can think of lots of ways to produce 0.75 milliwatts, just none of them will be more reliable than a lithium battery.
By sturdy, I mean, that any flat spot larger than a drunken college student's foot, should be strong enough to support a drunken college student. Likewise, any piece of equipment not strong enough to support a drunken college student, should not be exposed.
See what resources the folks on your fastest systems use, and assume everyone will use that much.
Expect it to ramp up to that usage over the coarse of a few months. Expect the usage to keep going up forever.
Those drives, no. Some 5 1/4 inch drives needed to be reformatted if you mounted them a different way. All the 8 inch drives were like that. I've never seen a 14 inch drive mounted anyway but horizontal. It would be bad.
As the disk drive arms get shorter, the less the angle matters. I've never heard of a laptop disk crashing because someone turned the laptop on its side.
Where would I find reliability ratings for disks?
Actually, for me, two year old models should be fine. 40 Gbytes is way more than I need for most of my systems. But, I want a new drive, not one that's been sitting on a shelf for 18 months. An old drive probably has some new failure modes, hardening of the lubricants or something.
- a shopvac has more than enough power, even if the hose is sucking through the hole of the CDrom.
Actually, too much power, too much noise, too big, and to control it, you need to control a 120V motor.
- A wimpy CPU fan doesn't have enough power to hold a CDrom. Much less to pick one up if things aren't in perfect alignment. (This particular CPU fan wasn't powerfull enough to keep my Athlon cool, that's why it was available for experiments.)
So a question for those who know pneumatics:What is a good cheap, small, relatively quiet fan/blower/pump for a robotic pick and place CD changer?
I think I'll probably take apart a cordless vacuum cleaner and use its blower.
My application is unattended archiving of data to CDroms. 2 copies of each CDrom is enough for me. One copy of 10 Gbytes of data takes about 15 CDroms. Pretty cheap if there isn't labor involved in swapping the CDs.
Search google for liquid nitrogen ice cream for recipes.
Try the string liquid nitrogen amateur scientist for experiments you can try at home.
Unless you've got a farm, farm uses aren't interesting. However, if there are farms near by that use it, there may be a liquid nitrogen vendor who delivers to your neighborhood.
A Dean drive generates reactionless force of a special type. To measure this force, we use a special unit, the Bathroom Scale pound. BS pounds are whatever my bathroom scale measures. My bathroom scale seems to be more sensitive than Dean's. When I stand still on it, I weigh about 195 BS pounds. If I shake my arms at the right speed, my weight drops to 175 BS pounds. That is better than .1 BS G thrust. I suspect a carefully tuned counter-weighted drill motor can do far better.
So when I finally get my device perfected and my paper published, some mean professor is going to explain that measurement equipment may produce incorrect readings in certain situations. That it isn't enough to get the reading you want, you actually have to show you got a valid reading.
For those who want to duplicate my experiments so far, get an aged Health-O-Meter spring scale. Other types of scale have some weird reality field around them that interferes with crack pot physics.
For a month every time I tried to call Comcast tech support, I got an "all circuits busy"
Someone else would quickly correct it with:
You are exagerating, it was only like that for about a week.
The "burnproof" technology makes it so that nothing catastrophic will happen when the PCI bus bandwidth is saturated.
What a coincidence, those devices seem to make up the rest of Microvision's product line.
Once they figured out how to scan the mirror fast and accurately enough, there are all sorts of uses. Bummer, most of them seem to be out of my price range for at least the next year, probably three.
You can tell it's not ready for primetime, the Spectrum color display system has a two pound piece that mounts on your head, tethered to a 40 pound box. I want one anyway.