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Comment: Re:left out the most important steps (Score 2) 93

by b1t r0t (#47133073) Attached to: How LEDs Are Made

The articled failed to mention the most important aspects of the LED manufacturing: wafering and the MOCVD that deposits the light emitting materials

It didn't "fail to mention" that, it started with the pre-cut dies. This place turns cut dies into finished LEDs, and they documented what they saw. This was in China, and the dies are apparently made in Taiwan (so maybe they are crap), and they weren't anywhere near there.

And yes, fabs are serious alchemy. Like the time when Fairchild was a new company, and they found out that their transistor yields were being affected by workers not washing their hands after taking a leak. The chemicals in urine were fucking up the process.

Comment: Re:Somewhat off-topic: why not uncut LED panels? (Score 3, Informative) 93

by b1t r0t (#47133003) Attached to: How LEDs Are Made

I work in a part of the commercial lighting industry, and the current technology is indeed surface-mount LEDs, sort of like what you see on strip lighting, only on a metal PCB (for heat dissipation, naturally). Just run everything through a pick-and-place machine and roll it through the reflow oven. The lenses are clear plastic light pipes mounted through holes in a metal fascia. (And I was lucky enough to be able to pick up a bunch of LEDs that fell out of the PnP when we were making some a couple of years ago. Heavy parts do that.)

I doubt they're ever going to move to mounting bare dies (like in seven-segment displays) because they'd have to have their own wire bonder and epoxy, and I'm going to guess that white LEDs need the phosphor applied between mounting the die and molding the lens, so that's one more step. Some customers want Made in USA stuff, and that would be a true pain in the ass to do die-mount in the US vs. a tube of surface-mount LEDs and a normal pick-and-place machine.

I'm pretty sure just from the way they look that traffic lights are using regular 5mm or 8mm LEDs. Even if they used surface-mount LEDs, they'd still need a lens somewhere, and die-mounts would of course be even more trouble. You would have to buy the whole thing pre-made from China with die-mount. The only reason seven-segment (and presumably matrix) LEDs use die mounts is that they can be sold as a single pre-packaged part, and they're too small to even use 3mm molded LEDs.

Comment: I feel their pain (Score 1) 105

by b1t r0t (#46344459) Attached to: Crowded US Airwaves Desperately In Search of Spectrum Breathing Room

I just upgraded my wifi to a dual-band base station so that I could use some of that sweet 5GHz space. I live in a suburban neighborhood (built in the '70s, so not even one of those super-cramped Krap Box neighborhoods they make these days) and I can see at least eight other SSIDs at any time.

After all, I've gotta watch those ATSC .ts streams from my MythTV on my laptop.

Comment: Re:Things haven't changed (Score 1) 249

by b1t r0t (#46105949) Attached to: Google Planning To Remove CSS Regions From Blink

15 years ago my biggest problem when dealing with HTML was when the clients were print designers.

I guess it hasn't changed. We aren't going to have display postscript on the small mobile devices that are so prevalent now.

Sorry, the web and print are two different media. It isn't going to look the same.

If you need really fine control use PDF.

Stop trying to cram a month's work of clothing into an overnight bag.

&tc.

We aren't going to have display postscript on the small mobile devices that are so prevalent now.

Doesn't iOS use the Quartz layout engine from OS X, which was specifically designed as a replacement for NeXT's use of Display Postscript? It uses a PDF model instead of a full Postscript model, but that also stops the sillier uses of your graphics renderer as a general-purpose programming language.

Comment: Re: Computers don't know how to be racist or sexis (Score 1) 612

by b1t r0t (#45766095) Attached to: Is Computer Science Education Racist and Sexist?
I learned to code on a TRS-80. WIth no internet. And cassette tape for storage for the first two years. There's this amazing invention you may not have heard about. You see all those words and pictures on your screen? People have figured out how to put them on paper, then they stack a bunch of these pieces of paper and glue them together. There are even places where you can read these stacks of paper for free.

Comment: Re:No. (Score 1) 612

by b1t r0t (#45765807) Attached to: Is Computer Science Education Racist and Sexist?
I was already playing with digital electronics and thinking like an engineer before high school. I even tried to build a computer from the chips available at Radio Shack in 1978, but sadly I hadn't quite grasped the concept of gate fan-out, or testing things in sections, at the age of thirteen. Not that it would have been easy without any test equipment more complicated than LEDs and an analog multimeter.

Comment: Re:CS Grads are unemployable (Score 1) 612

by b1t r0t (#45765769) Attached to: Is Computer Science Education Racist and Sexist?

Unfortunately, due to the economy, I there haven't been too many potential new hires for me to be involved in interviewing them. But when I did have some involvement, your observation was correct. The CS grads of today can barely code their way out of a wet paper bag, and they don't know any other language than Java when they even try. Like "write a file copy subroutine, and why did you make the choices you did". Yeah, computer science grads, they don't even understand how to do a buffered copy, much less how to determine your buffer size, which is one of the basic concepts of Computer Science. Nor do they seem to understand how to work with linked lists. (Were they asleep through their sophomore year data structures class, or what?) The EE grads actually knew how to program.

I was a CS grad of the '80s, but I already knew how to program and hook up TTL chips from my teen years, when it was all 8-bit, and from disassembling a Z-80 MS-BASIC. (That was MY "summer of code" from Bill Gates, with zero cultural bullshit.) For me, CS filled in a lot of the things I didn't know, like data structures class. The uni's equivalent of "Computer Engineering" was too hard to get through (mostly because low participation meant that the classes weren't taught every semester), but what classes from that major that I took as electives were for the FUN of it. Build a serial transmitter from TTL chips? No sweat, and then watch me flip those switches to make messages, since I knew the entire ASCII code chart in hexadecimal. Again, zero cultural bullshit, just me against some chips and wires.

Actually the main reason I didn't go EE was that I only wanted to mess with digital electronics. I didn't fucking care what the beta of a transistor was, or even why it mattered. Just give me a handful of 2N2222, some 220ohm, 1K, and 5K resistors, and LEDs. I know to respect transmission line characteristics because they will bite you in the ass, but beyond that "There be dragons here". Maybe that's why I'm so big on encapsulation in my code.

These days I'm doing embedded systems programming. Not much ageism in this part of the industry. I'm 49, and I have the least gray hair of the half a dozen or so programmers where I work. I'm the whippersnapper who actually figured out how C++ could make my code better. Just this past week I got an Ethernet chip working for the first time (which was kind of a bucket list thing for me), on a system with no OS. (So is there a pull-string Barbie that says "interrupt handlers are hard"?)

Comment: Re:Wait, what? (Score 1) 77

by b1t r0t (#45218567) Attached to: Book Review: <em>Minecraft</em>

Notch takes Infiniminer

Sorry, bullshit. First Minecraft video posted by Notch on 2009-05-13. Infiniminer source release on 2009-05-16. This means that Notch had been working on Minecraft for some time before Infiniminer's source code was released. Also, Infiniminer: .NET, Minecraft: Java.

So he didn't plagiarize anything more than the basic idea of a big world full of blocks. But Notch actually followed through to completion (more or less), while Infiniminer didn't.

As Steve Jobs was fond of saying, "Real artists ship."

Comment: Re:*Cough* United Kingdom *cough* (Score 1) 1387

I saw an article on one of the major UK newspaper web sites in the past week or two about some guy who lost hundreds of pounds after getting a stomach bypass. It referred to his weight / weight loss in stone. I was rather surprised that they still use stone over there beyond old men talking to each other.

Comment: Re:Shitfest of Kuro5hin (Score 2) 162

by b1t r0t (#42486955) Attached to: Rusty Foster Isn't Dead

I think part of the problem is that K5 has a mod system that lets everybody, even new accounts, rate every post with no limits, which encourages sock-puppeting and circle-jerking. (Kind of like... Digg and Reddit? Two down, one to go.)

Slashdot literally makes you lurk more, as an important factor in getting mod points is simply reading a lot of articles. Among other things, this makes it difficult for sock puppet accounts to ever get mod points. I guess it does require a certain critical mass of users to work properly, but below that level is probably admin-moddable anyhow.

There is nothing so easy but that it becomes difficult when you do it reluctantly. -- Publius Terentius Afer (Terence)

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