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Comment Blast from the past! (Score 1) 147

I built a 68000 based single board computer using parts from Motorola's M68000 development kit (or whatever that was called - it included a M68000, M68010, M68008, a couple of other 68k family peripherals, and a ream of documentation) as part of my master's thesis. Did a two-sided PCB with photoresist boards and hand-drilled and wired vias. The big difference then and now is the size of memory you can get in a single device - I was using 16K or 32K EPROMs and static RAM devices because that was pretty much the largest device available at the time (at reasonable cost, anyway - like $25 per chip). In your case if you're going forward with the full M68000 plan then I'd push forward with a real PCB. Those solderless breadboards really have horrible pin-to-pin capacitance and the inductance of all your wiring is going to give you nightmares. Nowadays you can lay out a board using free or cheapware tools and get a local shop to fab it (or you can do your own etching for the true back-to-the-80's experience) and you'll have something that's robust and repeatable. Good luck!

Comment Re:Just cheating themselves (Score 1) 438

One interview tactic I've used in the past (not with phone interviews) is to get the applicant to talk about some project they did, then dig into their understanding of the problem they were trying to solve until we hit bottom. This can make each interview pretty unique because not everyone thought the same thing was hard. And, every interview ends up with the applicant having to say "... I don't know", and there is no right answer. I'm sure that with enough effort, an HR contracting firm could game that process too, but it would take a while and it's still easy to punch outside of their envelope.

Comment Re:Worthless degrees (Score 2) 438

The cheaters and rote-regurgitators (just made that word up...) have effectively devalued all Indian scholarship. When you look at the questions posted on the various technical LinkedIn groups by Indian "engineers", it's immediately obvious that despite their "education" and job titles, they actually don't know anything and they don't even know how to go about learning something about what they don't know. Their attitude, overwhelmingly, is "I'm trying to do this thing, please give me the exact solution".

Comment Re:Charging amperage (Score 4, Informative) 395

Absolutely correct. Most electric cars (if you're keen, check out run at least 72V in a series string of at least 20 lithium-ion cells, and some run over 250V. Charging is done using a state-of-the-art high frequency AC/DC switching power supply with power factor correction, so that charging efficiency is maximized. For any given power transfer, double the voltage means half the amps, and that cuts the resistive power losses to 1/4, so it's always worthwhile to maximize the operating voltage within the bounds of the electronics (and safety considerations).

Comment Re:Charging amperage (Score 1) 395

Most electric cars run at least one series string of cells so that each cell will see the same charging (and discharging) current. There are 'battery monitor systems' that monitor the terminal voltage of each cell so that you can detect if one cell is reaching its capacity limit in either direction... that's when you're done charging or driving. The trick with series strings is to know that the cells are at least nominally identical in capacity and internal impedance; then, to set them each to the same state (either zero state of charge or fully charged; and then to connect them all, and drive or charge until you hit the other limit on state of charge. If you work within the limits, you will be able to do series charging and discharge with no damage, and you'll get a long life out of the cells.

Comment Re:This is good! (Score 1) 528

Maybe they're just not that smart....?



Perhaps they are behind where you were in terms of rote numeracy, but perhaps they have a deeper understanding of numerical objects than you did at that age?

I've spent pretty much my entire engineering career (25 years and counting) doing digital signal processing for realtime systems (voice coders, radio modulation and demodulation, GPS, inertial navigation, and graphics tomfoolery) and over time I've developed a pretty good grasp on numerical objects, algebra, and calculus, in fixed point, floating point, and modular field arithmetic. Certainly I know that stuff a lot better now than when I graduated, and I can think back through my schooling and see what was and what wasn't effective, from the basics through to a decently high level of applied math.

What I see my kids being taught, is basically a shotgun approach; but they spend so much time blasting them with alternate methods for doing things, that there is no time to teach the kids the underlying fundamentals which might help them tie things together; and the kids get confused between the different parts of the different methods so that instead of learning one or two methods fully and practicing it until they have it cold, they learn five methods superficially and forget the solution processes two days after the math unit ends.

Comment Re:This is good! (Score 1) 528

My kids went through the same thing with the multiple methods of doing multiplication... holy sh!t did it frustrate the hell out of the younger one because once he had figured out a method that was intuitive to him, all the other methods were just, in his opinion, superfluous wastes of time. Now I hear that the "new thought" is that, for some things such as basic single digit multiplication, rote memorization is in fact the most effective method and it leaves time free to work on higher level problems.

FWIW, I did my grade school curriculum in the Netherlands in the 70's and it was like this (from a math perspective): Grade1: Addition/subtraction; Grade2: Multiplication tables. Lots of recitation to drive the numbers into your head. Grade 3: Long division. Grade 4: Fractions. Grade 5: Decimals and bigger numbers. Grade 6: Common factor elimination in fractional expressions.

My kids are three to four years behind that timeline because of the unnecessary fluffery that seems to pervade North American education.

Comment Re:This is good! (Score 1) 528

Rote memorization is enough for math, hey? As others have already remarked, that will not work so well with division. Or algebra, or any other form of applied math. Or pure math. But I guess Ohio doesn't need to produce any math prodigies from here on. If you say "well, we can teach math methods so our kids don't have to be dumber than birds" then you have to teach logic (induction/deduction etc) so the kids can do proofs. Logical methods applied to everyday events (why do things fall?) begat the scientific method.

Comment Re:Years ago, I was involved in an edit war. (Score 2) 219

Having recently been involved in somewhat of an edit war (well, more of a "spirited discussion"... I'm in it for the long haul on behalf of my fellow Sunbeam Tiger owners), the "reliable citation" requirement is pretty much a nuclear handgrenade. Information is considered "reliable" if it's in a printed and published book by a "reliable source" which can be taken to mean "someone that writes a lot" - regardless of whether or not their writings are well researched in general or in particular. In our particular case, even appeals to demonstrable fact were treated with disdain because it was "original research" which is not permitted.

Comment Re:That is the best use of text messaging (Score 1) 211

But they're not. SMS messages are sent over the control channel on the cellular network (which is why they use much less of the system infrastructure than a voice call, which requires assignment of a voice/data channel, etc.) and they can stay fully within the cellular phone system infrastructure. No email relays involved.

Comment Re:Push the asteroid at the earth plz k thx bye (Score 1) 57

Ummm... orbital velocity is inversely proportional to its altitude above the earth. For LEO stuff, it's about 17,000 MPH (sorry about the units). If you want a faster velocity, you have to orbit lower, and then atmospheric drag would take it out within a few orbits. The moon's tangential velocity, relative to the earth, is only about 2700 km/h (or 1700 MPH).
The Internet

The Puzzle of Japanese Web Design 242

I'm Not There (1956) writes "Jeffrey Zeldman brings up the interesting issue of the paradox between Japan's strong cultural preference for simplicity in design, contrasted with the complexity of Japanese websites. The post invites you to study several sites, each more crowded than the last. 'It is odd that in Japan, land of world-leading minimalism in the traditional arts and design, Web users and skilled Web design practitioners believe more is more.'"

The hardest part of climbing the ladder of success is getting through the crowd at the bottom.