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I ran across Plucker about six months ago. Loaded the software on my Palm M100 and my main (Linux-based) machine at home. Now, any time I run across a neat article on Slashdot, if I don't have time to read it now, I create a quick script which "plucks" it and I put it on my Palm. At that point, I can read it whenever I like.

Current contents: Contracts in Cyberspace and the VCR-faq. I was trying to fix a VCR which didn't want to play EP tapes and was always having problems with the tracking. I didn't have to bring the VCR to my computer, and I didn't have to kill any trees.

That aside, I use the daylights out of the Calendar function; medical and dental appointments for myself, my wife and my kids, when certain bills are due, when I'm expecting such-and-such check or refund, etc. It makes it a lot easier to follow-up on something when you can put it in the calendar, with a note, and have it trigger an alarm a month or more down the road.

The Memopad gets used a lot, as well. If I'm talking to the insurance agent about my vehicles, I have the VIN numbers at my fingertips, as well as the license plate numbers. I keep a file with all my passwords for the various online places where I have accounts. I also have birthdates and SSN's for my wife and kids (I'm notoriously bad at remembering dates; having an alarm go off a week prior to a birthdate or the anniversary helps).

If we're planning a roadtrip (to visit family members elsewhere), I can put together a list (in the To-Do list) of everything which needs to go, and check them off when it comes time to leave. This also comes in handy when going to the grocery store. My wife will be telling me hours beforehand, "oh, and we need this and this and this," and I can mark them all down and check them off when I pick them up.

If you have a Palm, and you haven't gotten your hands on BrainForest, you need to look at it. I tend to think in "outline fashion," and this program help tremendously. Excellent for keeping notes which are more structured and organized than you might keep with MemoPad (and you aren't as limited in the size of your file, either).

Finally, get your hands on TextPlus. It takes a little getting used to, but once you do, it definitely improves your data input speed, even in graffiti. I just wish there was a way to use it in Windows and Linux; this kind of program could actually make a pen-based system an realistic replacement for a keyboard.

I swear by my Palm. I wish I had one with more RAM (M100 = 2 MB, not expandable or upgradeable in the firmware category). I used to have a IIIx, which had more RAM and upgradability; I miss it. Also, my M100 has a problem with NOT retaining its data when the batteries come out, so I have to sync mine regularly, then restore the whole thing after I replace the batteries (rechargeable NiMH batteries). In spite of that rather large pain in the neck, I still love my Palm. I'd be a completely unorganized mess without it. I hated carrying a paper-based planner; my Palm fits in my pocket, so size really isn't an issue.

Easier said than done.

If they use a CRC, it could be difficult to get something to the same checksum. Even if it's only a 32 bit CRC, there are a lot of numbers between 0 and 2^32 - especially when they are the result of some unknown hash function.

That's not to say it couldn't be done - the idea is akin to the 'The Club'(TM).....

Here is some background on lasers.

Let's put this falsehood to rest already:

NiCd Batteries do NOT have "memory"

>Anyway, that's what I learned. But, again, since I never took an EE course, I'm probably wrong.

No, you're not too far off, and I did say I flunked out, and there's good reason for that.

It's really not been my week. But I'll make up for my paragrah of less-than-prime information by providing a page of real information!

Anyways, unfortunately, since I haven't had a lot of real-world LCD experience, I can only tell you this -- LCDs are probably AC PWM (or duty cycle modulated) because LCDs last longer under an AC charge, and it is just easier to use PWM rather than a direct change in AC voltage due to the minute changes in AC voltage required to change contrast in an LCD without using PWM.

[Not that you can't change an AC voltage, of course...]

Basically you can either design a really stable circuit that can control the small amount of voltage change necessary to keep the LCD in its middle state, or you can fake it by turning it fully on and fully off fast enough that it appears grey. PWM is used all the time to save a few bucks, and there's no problem with it, except that you trade the effort involved in making a good circuit with the effort involved in finding the "magic numbers" that keep the LCD in the grey zone.

I was going to say similar comments. The Sci.Electronics.Repair FAQ has a wonderful section on salvaging parts which you could easily look to as inspiration or as just a great resource. Check it out.

Find it at
http://repairfaq.org/REPAIR/F_gadget.html

Not so. Macrovision works by pulsating the intensity of the video sync signal. This fluctuation in intensity fools the AGC circuit in the recieving deck causing the picture colors to become distorted, and brighter and dimmer. TVs do not contain this AGC circuit, and therefore, are unaffected by macrovision. A more detailed explanation can be found here: http://www.repairfaq.org/filipg/LINK/F_MacroVision 1.html#MACROVISION_016

2) lasers are generally grossly in-efficient when the power gets high; putting 1kw into a laser (i am drawing info from CO2 lasers, which is one of the easiest high-power infrared laser you can make) -- would yield a beam of ~ 100W. I am curious when they say it's a such such power rating -- is it the CONSUMED power, or DELIVERED power?

3) unless the IR radiation is really on the brink of visible, glass does not pass it. so, while your window might melt etc, you don't have to worry about getting blind *so* much. but indeed NIR passes through glass -- so there is still a danger, depending of what frequency the damn thing is -- if they want to be humane, however, it is easy to make the laser not pass through glass, though. however, with a high powered laser shooting down at me, i am somewhat certain that the first thing i will worry about is the melting metal and scorching skin.

p.s. IR radiation causes sub-surface burns -- so technically you won't have "scorching skin", but erm... die from IR laser is not something pleasant... FYI.

*lastly: i know i linked it before, but it's such a good site on lasers: Sam's laser faq

Don't forget that CDs spin backwards in Australia.

I have spent days pouring over the mass abundance of information there -- and it has convinced me that building a kilowatt CO2 laser to burn though buildings really is something everyone should consider doing for fun.

What ever happened to the Metamoderator. The /. l337 h4kr faggots who modded this up should be slapped silly.

Anyway, Here's how Macrovision works, and here is a link for a Macrovision remover that will actually work (I built one!).

MacroVision works by putting false sync and colour burst signals into the interlaced fields in a composite video signal.

This fools AGC (Automatic Gain Control) circuits into thinking they have a very bright picture, and so they reduce the gain. By varying the signal you can make the picture brightness pulse, or in some cases cause it to loose track of the synchronisation all together.

Conventional display devices don't have to have such accurate control of the gain of the signal, so are not very heavily effected, although it is possible to see the effects on some devices. You could see the high amplitude bursts, but these occur in the 'off screen' section of the field that holds the sync signals, and stuff like teletext - if you have vertical hold then you might be able to see them.

(For a great technical and non-technical explanation check Repair FAQ for an easy explanation check How Stuf Works)

Now originally this was intended to specifically block VHS style recorders, but as things have developed there is another device now in common use that can be effected, that wasn't around in consumer products when MacroVision was invented - the frame store.

These are handy digital devices that read the composite video signal in and store it in real time. The video can then be read out in any format you want. Why would you want to do this?

1) Stabilise the signal
2) Change video formats from 50/60 interlaced fields.

Now the first one is done during video editing so that different sources can be synchronised and things like picture in picture and wipe effects between 2 video sources will actually work. They are also now common in good prosumer VCR's for this reason. Digital camcorders have them by default because of point 2...

The second point is that it allows you to do standards conversion in real time - such as in a capture card where you digitise the signal to a different frame rate.

And here is the point - digital projectors such as LCD and DLP tend to use progressive scan rather than interlaced signals, so they contain conversion technology including frame stores to do the de-interlacing (good notes at SourceForge)

So any device that uses a frame store approach can be effected by MacroVision, it just depends on how good the AGC in the framestore is.

How do you avoid this? Simple really don't use a video signal that can have MacroVision on it. If you have RGB (component) then this won't have protection, and is the superior connection anyway for a projector. The S-Video source is normally ok as it seperates the chrominance and luminancne (colour and brightness) signals - although I've heard of a new 'level 2' MacroVision that can disrupt this - sorry no tech details on that I'm still looking, but I think it has to do with messing about with the chrominance.

Of course the fact you regenerate the signal from the framestore means a good one is able to strip the MacroVision out, but there are cheaper ways to do that, and no I'm not giving the links - spend 2 minutes on Google, and remember that MacroVision is specific to PAL/NTSC so don't go ordering abroad! A good legal reason to have such a device is to connect a non AV socket TV to a non RF output player via a normal VCR, or to connect a projector sensitive to MacroVision when you don't have RGB Component output. Of course in the US you will fall foul of the DMCA, but we already know what a mess that is!

Huh, it uses battery power. Well then, that makes the rifle thing easier.

BTW, the Sciam article shows plans for a laser that uses a capicitor made with foil and pcb electronic board. The capicitor made with this setup would be a couple feet wide. Some other people's designs call for a capicitor made with garbage bag plastic and foil. I think this is a better design because it has better capacitance. Anyway, for the rifle thing, I was thinkin' you could use the plastic and foil and just kind of put it into folds to save space, so you wouldn't have a 3 foot wide rifle. (of course each fold would have to be seperated! Need to use some kind of nonconducting support.)

Also, the Sciam design is not powerful enough. It produces 60 milliwatts. There are other designs with larger lasers that can make over 500 MW. That would be enough power to ionize air.

Anyway, a rifle of this design would weigh about 3 pounds, and be 1 meter long. The power supply and battery would be carried on your back and maybe weigh 20 lbs.

Anyway, this laser thing is very dangerous. Not only the electric beam, but the capacitor. The capicitor would be charged with 15,000 volt electricity. Nothing to screw with. People have been electrocuted when building homemade lasers before.

The best site for homebuilt lasers is Sam's Laser FAQ, Here

"A word about the philosophy of this site: These pages are declared to be a fluff-free zone! There will be no unnecessary, superfluous, or useless graphics of any kind - including but not limited to: dancing, gyrating, or other animated icons, colored textured backgrounds that are impossible to read through, or forced downloading of bit intense pictures that may be of no interest to you. Nor, will I ever expect you to use a particular brand of Web browser to be able to effectively access these pages. There are and never will be any advertisements, cookies, or other impositions on your time and space. In the time that it may take wading through a single monstrosity of the professional Web page designers at other sites, you will be able to find out what you want to know, when you want to know it! What a concept. :-) (Note, however, that your browser needs to be configured properly to make sense of the many ASCII diagrams, schematics, and tables. See the document: Suggested Browser Settings for font and other related information.)"

Amen.

Jesus!
I hope anyone using that kind of power makes sure they know what they are doing.
Because the IR beam is invisible your eye will not have a blink reflex to bright IR light. The first you will know about getting an eyefull of a powerful IR laser is when you blind yourself (or someone else)
You have no pain receptors on your retina.

Remember home made lasers can be an absolute bastard to align! A good staring point for information on home made lasers is Sams Laser FAQ
A good background to semicondutor lasers is Britney Spears Guide to Semiconductor Physics (Yep, its true! check out the link.)

This circuit was not isolated from the power line and has been removed due to the danger involved in such a setup.

Although web archive's archives of the Repair FAQ only go back to 15 Feb 2K1, if I remember correctly the removed link went to the page Slashdot is linking too. Word from the wise: I'm not saying Nixies are inheirently dangerous, but many schmatics involving Nixie tubes do not isolate from the power line. And don't forget the big red warning on the page:

Warning! As this design uses a transformerless power supply, the whole circuit is at mains potential. Disconnect before making any adjustments etc. If you need to use an oscilloscope for debugging, the circuit MUST be operated through an isolating transformer.

You might try building a device like this which would allow you to interface directly with the drive controller. [If you don't need something as complex as shown at that link, I'm sure with the references linked from there, you could put together something].
By doing this, you could apply power to your drives before you boot, and use something similar to what's described above to spin them up.

This would allow you to control the high current draw by spinning the drives up in whatever order you'd like before you electrically remove the "spinner-upper" from the drive electronics and allow the computer to boot normally. (This is assuming that a 2nd spin-up signal from the BIOS wouldn't freak out the drive.)

You can find an IDE Hardware Reference & Information Document here.

To be very honest, I can't really see anybody implementing something as complex and convoluted as what's described above, particularly for multiple drives - but a properly programmed PIC chip or development board, with a bunch of IDE headers for the drives, that could spin up the drives however you'd like, then pass-through the original IDE signals from the motherboard, at boot time - POTENTIALLY, Potentially Could ... save you the forty bucks an additional PS would cost you.... :)

You can see another suggestion of mine for this project here.

Good luck!

Linkie

This is a popular myth.

Check out http://www.repairfaq.org/ELE/F_NiCd_Memory.html and the full NiCd Battery Frequently Asked Questions file at http://www.repairfaq.org/ELE/F_NiCd_Battery.html before you flame me about this.

This is a popular myth.

Check out http://www.repairfaq.org/ELE/F_NiCd_Memory.html and the full NiCd Battery Frequently Asked Questions file at http://www.repairfaq.org/ELE/F_NiCd_Battery.html before you flame me about this.

That's a bit oversimplified. See this note on octane measurement for a more comprehensive version.

Before you try to educate someone else, start with yourself! The light/dark pattern thats seen with the experiment you describe is nothing more than an interference pattern created when the monochromatic and coherent light reflects off the surface of the object you're looking at and strikes your retina.

For a more complete description, take a look at:

http://www.repairfaq.org/sam/laserioi.htm#ioiscs0

Now, as far as eye resolution goes:

"For an eye with 20/20 vision, the angular resolution is 1 arcminute (1/60th of a degree)"

With this information, we can make a good guess at what a monitors resolution "ought" to be.

Take the sine of 1/60&#186 and multiply this by the aproximate distance from the monitor.

At 3 feet, you get about 0.0105 inches. So you need about 100 pixels per inch. Thats 10,000 per square inch.

A 17" monitor is about 13"x10", so a resolution of 1300x1000 should do the trick at 3 feet.

Also, notice the qualifications I made

A 17" monitor...

...at 3 feet.

This shows that the statement: "The human eye can see aliasing artifacts at resolution up to and even beyond 4000x4000, so obviously 1600x1200 is not sufficient.

is meaningless without knowing the viewing distance.

But even knowing the viewing distance still gets us no where. Notice the ought above in quotes. No matter what the resolution of the monitor, there exists textures that will cause aliasing unless other steps are taken. Outline of a proof:

1) Cast one ray from the virtual eye (POV) through each pixel of the screen onto a surface parallel to the screen, but some distance away in the virtual world.

2) Where the cast rays meet the surface, find the texture element of the surface at this intersection and color it white.

3) Color the rest of the texture elements black.

It should be obvious that the surface viewed at this distance with this texture and without anti-aliasing will appear totally white. It should also be obvious that for any resolution we can create a texture that will cause this effect.

This reminds me of Microsoft's response when I pointed out a problem with one of their C++ libraries: "It isn't a bug. It's a limitation." That slogan was my .sig for years.

"It isn't a bug. It's an exclusive Microsoft feature."

This would make Windows 95/98/2000/Me/CE/NT what, a cockroach motel?

Where did I put that rare earth magnet? ;']

And this lead leaches out of the glass in the landfill how?

And while we're at it, the talk of banning lead solder seems also to be a crock - the non-lead alternatives to solder have higher melting points, meaning changes to manufacturing processes for chip and board alike.

Now, leaving aside the expenses that these changes will add to your gear (because like a good envionmentuhlists, we all believe that any cost is justified "even if it saves one chiiiyuld"), you've solved one problem, but created another one, namely:

Crappy solder means higher failure rates, which means even more crap thrown into landfill.

This is fine if you're a manufacturer - you get to sell the customer two $59.99 VCRs and a $150 TV every couple of years as the solder joints - already crap in most consumer gear as witnessed by the flood of complaints in sci.electronics.repair - go cold on you and the customer can't be bothered to get it fixed because the cost of "junk it and buy a new one" is less than the cost of "fix it".

All that's changed in this wacky EU proposal is that the gummint gets to charge the company another ~10-20% as a penalty for making disposable crap - the company then passes the costs on to you. It's no skin off their nose when the consumer would rather have a $150 (or $150+$20 "green" tax buried in the price = $170) piece of crap than a $500 piece of equipment.

You wanna really help the environment? Screw this "gummint oughta tax manufacturers who make products we don't like" crap. Just do two things:

• Press manufacturers to build quality into their products the way they used to. Gear made in the mid-80s is still going strong - gear made in the mid-90s is mostly crap. Be willing to pay 15% more for a screen that'll last 5 years longer than its bargain-bin neighbor.
• Reuse, don't recycle. My current TV is a 27" set that someone left out for garbage. The fault was a $0.25 capacitor that took out a $3.20 amplifier chip. Because the previous owner cut the AC cord on the thing (presumably they didn't want anyone trying to fix it - fsck that!), I spent another $5.00 on a cord from Rat Shack. The goddamn cord was my biggest expense.

Now, not everyone can (or should!) fix their own gear, especially if it's a TV set. But that fix was trivial, and any repair tech would have recognized the failure instantly (vertical deflection failures are common on this model), and said "$5 for the new parts, $50 for knowing which parts you need".

Hell, even if you don't want it fixed, consider giving it to a local repair tech. "Hey, if you can fix it, it's yours, find someone who wants it".

Back to my set - that set was made in 1993, just at the start of the decline in consumer electronics quality. But it's still going strong a couple of years after I picked it up. I fully expect this set to last until HDTV renders it (and all our other sets) obsolete in 6-8 years.

(And yeah, I'll be stocking up on lead solder, just in case it's banned by the time I need it to fix something!)

Side note -- the real cause of failure in that set - and many monitors and TVs - was dust buildup. High voltages used in monitors and TVs mean lots of static to attract dust. The dust coats the components, trapping heat. The heat is what killed the capacitor, resulting in the failed amp chip.

Practical upshot -- if you read a few FAQs (e.g. http://www.repairfaq.org) and learn the basic safety rules for working in a monitor, you can probably save yourself a lot of headaches by just getting in there and cleaning out the dustbunnies every 5 years.

Less heat. Less stress on parts. Less landfill. Happier planet.

Or to borrow an old WWII slogan: "Use it up, wear it out, make it do, or do without."

This ain't new, kids.

Ooooooh no they don't. Well, not in any way that's relevant for pretty much anyone's purposes.

I direct your attention here and here for a detailed explanation.

In brief, what most people call "memory effect" is really a combination of voltage depression resulting from the overcharge performed by all consumer battery chargers, and natural cell aging. Voltage depression does not greatly reduce cell capacity, but it does change the shape of the cell discharge curve - the cell's voltage drops abnormally early in the discharge cycle from the normal 1.2 volts to 1.05 volts or so, which may cause some devices to believe the cell is flat, because a normal NiCd IS very nearly flat when its terminal voltage has fallen this far. A voltage depresed cell, however, can actually deliver about the same amount of energy as it ordinarily would.

Genuine memory effect is very, VERY seldom seen, only occurs in sintered plate NiCd cells, and is in fact CURED by overcharging! Nickel metal hydride batteries are utterly immune to genuine memory effect, although they, too, can suffer from voltage depression.

Ooooooh no they don't. Well, not in any way that's relevant for pretty much anyone's purposes.

I direct your attention here and here for a detailed explanation.

In brief, what most people call "memory effect" is really a combination of voltage depression resulting from the overcharge performed by all consumer battery chargers, and natural cell aging. Voltage depression does not greatly reduce cell capacity, but it does change the shape of the cell discharge curve - the cell's voltage drops abnormally early in the discharge cycle from the normal 1.2 volts to 1.05 volts or so, which may cause some devices to believe the cell is flat, because a normal NiCd IS very nearly flat when its terminal voltage has fallen this far. A voltage depresed cell, however, can actually deliver about the same amount of energy as it ordinarily would.

Genuine memory effect is very, VERY seldom seen, only occurs in sintered plate NiCd cells, and is in fact CURED by overcharging! Nickel metal hydride batteries are utterly immune to genuine memory effect, although they, too, can suffer from voltage depression.

For all those without a PS2, try reading this

It's called Macrovision and it's still in use today --- a nastier version is in use in DVDs. As for the 'descramblers' they are still around, check at SIMA.
---

WARNING: DO NOT EVER AS LONG AS YOU LIVE THROW AWAY THE BOX OR ANY OF THE PIECES OF STYROFOAM EVEN THE LITTLE ONES SHAPED LIKE PEANUTS.

If you attempt to return the device to the store, and are missing one single peanut, the store personnel will laugh in the chilling manner exhibited by Joseph Stalin after he enslaved Eastern Europe.

Besides the device, the box should contain:
...
Eight rectangular snippets of paper that say "WARNING"

...
...

WARNING: WHEN YOU ARE LAYING THE PLUG ON THE FLOOR, DO NOT HOLD A SHARP OBJECT IN YOUR OTHER HAND AND TRIP OVER THE CORD AND POKE YOUR EYE OUT, AS THIS COULD VOID YOUR WARRANTY.

...
...

WARNING: WE MANUFACTURE ONLY THE ATTRACTIVE DESIGNER CASE. THE ACTUAL WORKING CENTRAL PARTS OF THE DEVICE ARE MANUFACTURED IN JAPAN. THE INSTRUCTIONS WERE TRANSLATED BY MRS. SHIRLEY PELTWATER OF ACCOUNTS RECEIVABLE, WHO HAS NEVER ACTUALLY BEEN TO JAPAN BUT DOES HAVE MOST OF "SHOGUN" ON TAPE.

...
...

WARNING: IT MAY BE A VIOLATION OF SOME LAW THAT MRS. SHIRLEY PELTWATER HAS "SHOGUN" ON TAPE.

if I understand Macrovision correctly, it is basically a non-chaotic bit o' noise added to the NTSC signal).

Macrovision works by periodically flipping the signal in the vertical blanking region from black to white. It flips it every few seconds (somewhere in the range of 5-30 seconds, it seems) and does it randomly. The reason this works is that almost all VCRs manufactured after 1986 or so do some manner of auto-gain-control, by assuming that the blanking region is the reference black level. So when it goes white, the intensity of the recorded picture goes all wonky.

Most televisions don't do this gain-control trick, which is why this works: it will mess up VCRs but not CRTs. Of course, it also messes up any TV that behaves more like a VCR than a CRT, such as LCD projectors.

You can get a device that defeats Macrovision for about $40 from the back of any video magazine. The way they work is by taking the input video signal and painting a black stripe over the blanking interval. As far as I've seen, this causes no loss of picture quality.

There is a Macrovision FAQ, including schematics on how to build your own filter.

if I understand Macrovision correctly, it is basically a non-chaotic bit o' noise added to the NTSC signal).

Macrovision works by periodically flipping the signal in the vertical blanking region from black to white. It flips it every few seconds (somewhere in the range of 5-30 seconds, it seems) and does it randomly. The reason this works is that almost all VCRs manufactured after 1986 or so do some manner of auto-gain-control, by assuming that the blanking region is the reference black level. So when it goes white, the intensity of the recorded picture goes all wonky.

Most televisions don't do this gain-control trick, which is why this works: it will mess up VCRs but not CRTs. Of course, it also messes up any TV that behaves more like a VCR than a CRT, such as LCD projectors.

You can get a device that defeats Macrovision for about $40 from the back of any video magazine. The way they work is by taking the input video signal and painting a black stripe over the blanking interval. As far as I've seen, this causes no loss of picture quality.

There is a Macrovision FAQ, including schematics on how to build your own filter.

Heh. Reminds me of Dave Barry's "Read This First" column.

Instructions: For results that can be the finest, it is our advising that: Never to hold these buttons two times!! Except the battery.

I love it. The full text can be found in "Dave Barry's Greatest Hits" or the sci.electronics FAQ under humour. ( www.repairfaq.org).

Careful, such methods of preventing copying have happened, worse yet, without most people knowing it.
For example, try renting Disney's Aladdin. Now try copying it. Ugh, why is it so dim? Why so bright? It's MACROVISION. It's stops all but the most "avid" pirates (willing to buy/build protection defeats) from copying VHS tapes and DVDs to VHS tapes... See Macrovision FAQ for more details. Of course, you'll also be prevented from making backup copies of tapes too... Try it and find out! Macrovision was an afterthought to VCRs as well... Bummer.
Since audio is unprotected on CDs I guess this doesn't count. Just think of it as a friendly reminder of how copy protection HAS at least once worked as an "aftertought" to a medium/format.