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Comment Re:There was nothing to catch (Score 1) 115

Much like testing for certain medical diseases, sometimes you can only determine a cause by exclusion.

  • A phone that is turned off is consuming no power, so the failure cannot plausibly be caused by an excessive rate of discharge or by external heat (e.g. being too close to a hot GPU).
  • A phone that is not charging is adding no power to the pack, so the failure is probably not caused by an excessive rate of charge or by overcharging.
  • Multiple battery manufacturers use different battery chemistry and different designs, so the failure cannot plausibly be caused by dendrites or other similar failures. Also, the failures don't occur with those same batteries in other devices, which eliminates the batteries themselves as a likely cause.

When you eliminate the impossible, what remains are failures that can occur even with a battery that is neither charging nor discharging. The most likely causes, then, involve some form of physical damage.

LiPo packs change size during normal charging and discharging just a bit. That's why there are tolerances build into the design. With insufficient tolerances, bad things happen (TM), and even if the tolerances are sufficient to avoid self-puncturing at their maximum size, it is possible that flexing the case in just the right way while the pack is maximally swollen could still puncture the pack. So this is at least a plausible explanation, whereas most other theories aren't.

With that said, even if we assume that these folks are correct, it does not absolve other aspects of the design. Not all failures have only a single root cause. For example, IIRC, overcharging a LiPo pack can cause unusual levels of battery expansion from hydrogen buildup, which when combined with normal levels of flexing in a case that has insufficient tolerances, would result in the pack perforating and venting with flame.

Comment Re:Bad Headline (Score 1) 579

The other companies gave no answer, which for any company that didn't have a history of inadvertently enabling genocide was IMO the right thing to do. Such political trolling really shouldn't even be dignified with a response, in general.

But you're right about IBM. Ethically speaking, they should have been the first to say no, given what happened the last time they helped with a database of everyone in a particular religious group. Then again, it is also possible that because IBM and its employees were not punished for their role in enabling the Holocaust, the bean counters that run the place would dutifully enable another one. Scary thought.

Comment Re:Apple bears some responsibility here. (Score 1) 118

The G3 series had a ferrite choke a quarter inch from the plug, and that quarter inch of wire constantly broke, causing fires, so they recalled the entire lot of them and replaced them with the yo-yo power supply.

Slight correction. I'm not sure if they actually caused fires; they were recalled because they considered them to be a fire risk from overheating, which presumably was caused by shorting caused by the cable failures.

Comment Re:Apple bears some responsibility here. (Score 1) 118

Insulation plastic falls apart after a year? Hm, tell that to the PSU for my Macbook Pro bought in 2012... Still in perfect condition. But then, I never wind the cable using the ears, I always just wrap it around the PSU itself while leaving a generous loop from where the cable exits the PSU.

It has nothing to do with how you wind it. I've seen Apple power supplies that were never wound up at all where the outer insulation became brittle and flaked off in large chunks. I'm not sure if it was sun exposure or heat exposure, but something causes the jackets on the early MagSafe cables to chemically break down.

Comment Re:Apple bears some responsibility here. (Score 1, Informative) 118

Case in point: Mac laptop chargers have been known to suffer from frayed cables due to Apple's insistence on a design that lacks adequate strain relief. This has been a known engineering defect in their chargers since the PowerBook G3 series design almost two decades ago ...


As far as I'm aware, Apple has never in its entire history built a good laptop power supply:

  • The original PowerBook 1xx series had connectors that kept breaking. IIRC, the 5xx series was similar.
  • The G3 series had a ferrite choke a quarter inch from the plug, and that quarter inch of wire constantly broke, causing fires, so they recalled the entire lot of them and replaced them with the yo-yo power supply.
  • The yo-yo design had no real strain relief, and even better, had thinly insulated wires inside a steel-braided shield that over time wore through the insulation, resulting in cables that sparked internally. In a dark room, you could see little blue electrical arcs in the middle of the wires.
  • The iBook power supplies had inadequate strain relief and broke right at the plug end.
  • The T-shaped MagSafe connectors had the same problem.
  • The L-shaped MagSafe connectors were usually more reliable, though they still eventually fail at one end of the wire or the other, but the MacBook Air version was notoriously bad.
  • And MagSafe 2 is a disaster of failed strain relief.

So saying that third-party Mac laptop supplies are worse than the real thing might be true, but it is like saying that a Pinto is worse than a Corvair. They do, however, build reliable USB power supplies... but their cell phone power cords are even worse than their laptop power cords. Fortunately, there are many third-party manufacturers building Lightning cables that are actually built to last.

Comment Re: Apple problem mostl or platform-independent is (Score 2) 118

Part of what makes these problematic is largely that they're trying to look like Apple products. Apple makes really small power supplies, which makes it much harder to create knock-offs that work. Nobody makes knock-offs of Android supplies; they just make cheap USB power supplies. Because they aren't trying to hit an absurdly small form factor, they don't cut corners to the same degree, and the supplies tend to be more reliable at a given price point. That said, the Apple USB supplies cost $19, and the usable third-party branded supplies usually start at about $12, so there's not a lot of savings to be gained even when you take away the form factor.

More significantly, because they're trying to look like Apple products (and often pretending to be Apple products), they can't be branded. If they were, Apple would go after them for violating their design patents (and trademark violations if they use the Apple logo). That entire selling model is incompatible with branding. As a result, there's no hit to their reputation if the product doesn't work. They just change the name on their Amazon or eBay account and go right back to fooling people. So there's also no incentive to make a quality product.

Comment Re:I'd like a "stop charging at 80%" feature (Score 1) 91

So how come it continues to charge after hitting 80%?

Because that's a lot of capacity to lose. I doubt that the difference between stopping at 80% and stopping at 100% is enough to be worth the rather significant loss of capacity.

That said, the OS already does various tricks to minimize the damage caused by fully charging the batteries. For example, in OS X and iOS, IIRC the top several percent are hidden. When the charge level hits about 95% (I forget the exact number, and it might even vary depending on the age of the battery), it says 100%, but it continues to charge for a while at a slow speed until it reaches a true 100% charge. As the pack discharges, it gets down to about 95% before the UI stops saying 100%.

The reason for this is that the charge circuits in the devices won't even start charging until the pack's charge drops below about 95%, because continuously trickle-charging batteries to keep them at 100% will burn them out rather rapidly, whereas letting them cycle by five or ten percent is much less abusive on the batteries. However, it would be confusing to users if their batteries rarely read 100% after a full charge, so they fudge the numbers so that 95% is treated as fully charged.

Comment Re:always fascinating to see such drivel (Score 1) 278

This is why the only way to fix such a broken system is to get the people so mad that they self-organize to overthrow the bad leaders and stick their heads on pikes as a sign to anyone else who would go down the same path. It worked reasonably well in France, among others.

Unfortunately, that doesn't work very well if the government has tanks and fighter jets, which is why Russia's arms sales to various Middle-Eastern regimes represents such a grave threat to real, long-term stability in the region.

Comment Re: Change the law (Score 1) 1425

Keep in mind that California's budget is in the triple-digit billions of dollars every year. A mere $4 billion dollars is chump change. That's like somebody who makes $100 grand a year taking out a loan on a low-end used car. The economy was in the toilet, and California was bailing water just to stay afloat. Taking out a little temporary debt to avoid massive cuts in services was the fiscally responsible thing to do.

But in addition to that, he also pushed for changes to the law that required a certain portion of revenue in unexpectedly profitable years to be saved instead of getting spent, so that in future lean years, the state won't have to take such drastic measures to keep from having to cut essential services. That's fiscal conservatism.

Comment Re:Not good enough... (Score 1) 95

It should be that the user HAS to have purchased the item. Why would you do it any other way?

Because sometimes there are very useful reviews by people who chose a different product (or chose to not buy a product at all) after discovering serious flaws in the product while looking at it in a brick-and-mortar store.

Comment Re:Some things never change (Score 1) 434

The GP's point was fundamentally invalid, because the proposed law didn't regulate anything. The law gave the FCC the authority to create future regulations that promoted diversity in ownership if its commissioners determined that doing so would serve the public good.

Arguing that it was an attempt at banning right wing radio is like arguing that passing a federal law that allows states to pass laws that recognize gay marriages is a nationwide ban on Christians. It's pure and utter nonsense.

Comment Re:The needs of the country have changed? (Score 1) 1425

I learned that the point of the electoral college was to insure that a candidate would have to win support from a wide variety of voters, and not just a numerical large group in large cities. If there were no electoral system, candidates would campaign almost exclusively in New York, Chicago, LA, and a hand full of other large cities where large numbers of people live.

Even with the electoral college, they still do that. The only difference is that they campaign almost exclusively in Atlanta, Nashville, Memphis, Jackson (MS), and other large cities in low-population states and ignore the big cities in all the high-population states.

Comment Re: Change the law (Score 1) 1425

I certainly hope so. I hope a lot of other states do the same. Giving taxes to the federal government just to have the cash given back is inefficient and pointless. Otherwise, we'd be better off lowering the tax rates and letting the money stay here (I live in California).

Yes and no. When we talk about how much goes back into the states, we're including military spending, federal government contracts, interstate highway improvements, etc. The federal government owns the interstate highway system, employs the military, etc., all of which at least arguably needs to go through the federal government. And the federal government pays money to contractors in various states to build things that it needs. So it really isn't anything like getting a tax refund.

Either way, my point is that there's a huge discrepancy between the richest states and the poorest states, with the poorest states getting back several times what they put in, and the richest getting back only about four-fifths of what they put in. It is basically federal redistribution of wealth from the richest states to the poorest states. And the poorest states keep voting for people who say that they're against redistribution of wealth from the rich to the poor. They're voting exactly contrary to their best interests, and if they ever actually truly got their wish and California and a few other blue states stopped propping up their governments, most of the southern states would have to immediately declare bankruptcy; they're only solvent because of policies that they claim to be against.

Comment Re: Change the law (Score 4, Interesting) 1425

None of those cities have problems because of high taxes. In order:

  • Detroit's problems are largely the result of white flight in response to the race riots of the 60s. The city never really recovered, and as a result, there are entire formerly wealthy neighborhoods that are nearly abandoned.
  • Chicago's problems (and really, all of Illinois) are mostly the result of Democrats who voted like Republicans by massively outspending their revenue, racking up ridiculous amounts of debt. Add some corruption and cronyism in there to make things even more messy.
  • Baltimore's story is similar to that of Chicago, but with more corruption.

Amusingly, California almost got into trouble the same way—by taking on too much debt without adequate stockpiles of cash to weather economic downturns. One of the better surprises in California politics was getting two fiscal conservative governors in a row—Schwarzenegger and Brown—who have pushed some useful reforms that will really help the state over the long term.

It's unfortunate that the Republican party has drummed out most of its fiscal conservatives in favor of Reaganite faux conservatives who are even more fiscally irresponsible than the worst of the Democrats. If there were a non-negligible number of actual fiscal conservatives in the Republican party, the red states wouldn't be in nearly as bad shape as they are. Both parties need more fiscal conservatives.

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