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Comment Re:This is why you call your bank before tourism (Score 2) 210

Maybe because it's not uncommon to test a stolen credit card with some trivial amount first, before making a huge purchase with it. That, combined with it being foreign, probably triggered the fraud alert.

Maybe it's obvious, but if you're having bad experiences with your bank, maybe you should... try a different bank? I can recall only a few instances where my bank has suspected fraud, and they've always called me before my card was deactivated. Once was when I moved halfway across the country, and I spent $350 at Target for random housewares - while I was loading the bags into my car in the Target parking lot, my bank called to make sure it was me. On the other hand, I've travelled to a number of different countries (often without notifying the bank), and I don't recall ever having a problem with my card.

I'll take a stab in the dark, and say it's because my card is through a large but local credit union, where they actually care about individual customers. I think the huge national outfits tend to care about customers in aggregate - if they can offer a better deal than everybody else (e.g. more cash back, or a "double" rewards card), then it doesn't matter if they lose you as a customer - they'll pick up two more to replace you. But that means that to maintain their margins, they have to catch fraud with a much higher false positive rate, because they can't afford any loss.

Comment Re:So, How Much? (Score 1) 176

That is one option, but you can buy them too (including installation and inverter, of course; they're not in the business of selling just a panel). I bought my system from them; I owe nothing for the next 30 years or so, but they owe me a warranty, insurance, and a minimum production guarantee. I still have to pay the minimum monthly charge for my power bill to the power company, of course - I'm not off-grid, just roughly net zero.

If I sell my house, the benefits go to the next owner (who also would have no liability to SolarCity), or I can pay $500 to do a site survey of my new house and another $500 (if the survey is acceptable) to move them to the new house.

And because I own the system, I get the rebates, not SolarCity. (For me, that was just the federal tax credit, no utility incentives or anything like that.)

But their usual sales pitch is either the lease or (new in the last year or so) a loan that is paid off based on energy production. Many people prefer that because you don't have to come up with tens of thousands of dollars all at once, and you start paying less for power immediately.

Comment Re:Licences (Score 1) 572

The door swings both ways - you can't impose your political beliefs on me, and I can't stop you selling the software in your homeland either (unless you're doing something illegal there, etc.).

Don't worry, he's stopping *himself* from selling the software in his homeland. Although the term "selling" is generous - it's a free license. And as Wikipedia notes, the license distributed with the software states that the license is valid until the next version of the program is published, at which time the new version's license will apply to the older version - but no new version has been released since 2011; so in case anybody is still using this crackpot's software, they can just ignore all his crazy licensing changes in the past year.

Comment Re:Where in the USA? (Score 1) 142

+1 to this. Verizon almost always has the best coverage (though right now, I'm vacationing in a spot that has AT&T but not Verizon, surprisingly). AT&T has good coverage of interstates and any city of probably at least 10,000 or more. Smaller cities may or may not have great coverage. T-Mobile and Sprint are less expensive, if you're willing to sacrifice coverage, though they're usually good near urban areas.

Comment Re:Not enough data (Score 1) 105

But that was exactly my point; Google knows about trees, and they have 3D models of them. Not everywhere in the world, but at least in the areas that Sunroof is covering now (and many others - like I just checked my parents' house in Wisconsin). As to your "most people don't live in urban areas" comment, the US Census Bureau would say otherwise. According to them, it's about an 80%/20% split between urban and rural.

As far as SolarCity, they put exactly what they can charge you in their contract. If someone didn't read the contract to find out what they'd be paying, that's their own damn fault. Personally, I got my solar panels from them, but I bought them outright - no lease, loan, or power purchase agreement. They still warrant both functionality and energy production (with a per-kWh payout if they're too low) for 30 years, but I owe them nothing. That said, the sales guy I dealt with was a bit of an asshat, trying to push me with high-pressure tactics. In the end, they were still the best deal, both in terms of price and future maintenance, and everybody besides that one sales guy was very nice.

Solar certainly doesn't make financial sense for everybody. And you can't put a solar system on every roof today and expect the grid to still function (see: Hawaii, where many places are not allowed to add new solar systems). However, California (for example) is mandating that utilities build a lot of energy storage, to help smooth out the burst of solar power available, so more people can install it. A friend of mine works for a company that provides such storage, in the form of gigantic flywheels.

In any case, for many people, solar is a good idea. Google's tool helps you determine what makes financial sense in your particular situation. And its estimates (compared to what I actually paid and what my panels actually produce) are more accurate than many of the other estimates I saw while shopping. And even if it's not a financial positive, some people prefer solar just to reduce the amount of carbon and other pollutants they are contributing to the atmosphere. As for your case, yeah - maybe the trees make it unprofitable to install solar. Or maybe you could do it, but you'd need more expensive microinverters to help counter the shade. The point is, this tool can tell you. (Well, at least it could, if it were offered in your area.)

Comment Re:Not enough data (Score 1) 105

You're not being very imaginative. They don't need to take pictures every few minutes all year to find shadows; they just need a 3D model. The sun's position in the sky is easily calculated for any given day of the year and time. And they have 3D data (probably collected by airplane) for many areas, as seen in Google Earth or Satellite View on Maps. The data's not perfect (if you've looked at the 3D trees, they're pretty ugly!), but it's a pretty decent tool given that nobody needs to climb on your roof to take any measurements to get a decent idea of how effective solar panels would be. It pretty clearly shows the west side of my house as partially shaded, due to a line of trees nearby. I have some friends who live a mile or two away from me, and their house is almost entirely shaded - and shows as such.

In addition to getting data about shadows from things near your roof (trees, other buildings, etc.) they're also apparently including data based off of weather patterns. So, for example, in my area, where mornings are often cloudy and afternoons are almost always sunny, the west-facing surfaces show up as sunnier than east-facing surfaces. Another area that's covered by this project doesn't show the same effect, because they don't get the morning clouds. Heck, it even picks out the chimney on my roof, and shows the area around it as slightly less favorable.

That's not to say it's perfect - it makes some small mistakes on the roof shape on a lot of houses. For example, it thinks that a pergola attached to my house is part of the south-facing roof. And a nearby neighbor with an odd-shaped roof line looks even more odd in Sunroof, as if it had been architected by a Cubist. But it's a pretty good first cut, and a nifty use of their extensive data to make something new with not too much extra effort required. That said, if you're serious about solar, whoever installs it is going to do a site survey that basically determines this for you anyway, and they will hopefully pick the best surface.

My panels actually face East, which is uncommon - but it was the largest available area, and has the least shading from trees. Sunroof shows the South side as being better for my house (and West worse, due to trees), but a lack of contiguous area on the South made the east side less expensive per kWh produced. (The South side would have required more expensive higher-efficiency panels, driving up the cost of the system.)

Comment Re:Just use Stuxnet (Score 1) 78

Yeah, I was gonna suggest this. Just put your update on a USB thumb drive with a rootkit, leave a few out in the parking lot, and wait. Someone will plug it in, at which point your drive can take over the machine and update it!

At that point, you might also consider installing something else to help dodge the air gap to make future updates for your customer even easier; for example, try data transmission via ultrasonic frequencies to another compromised^w updated machine with a network connection!

Comment Re:One solid year? (Score 4, Interesting) 34

Perhaps OP was thinking of what they promised (a 5-year flight), or perhaps my quick googling is insufficient... I was able to find a 14-day unmanned solar-powered flight in 2010 from Qinetiq's Zephyr craft.

Following the link to the article (I know, I know, this is slashdot, we don't do that here), there's an important qualifier missing from the summary; this is a record for an aircraft *in its class*. Specifically, that class is aircraft under 50 kg total mass. They do cite the Zephyr (now as an Airbus property) as the longest UAV flight, and Solar Impulse 2 as a longer flight by a (manned) solar airplane. It is also notably different than the Zephyr because it is a "low-altitude" vehicle. From one of the research papers on their website (OK, I realize this is getting out of hand... I mean, following the link is one thing, but doing a google search for the company involved???), it looks like they're staying below 1,000 meters. The Zephyr is intended to fly between about 60,000 and 70,000 feet, where winds are weaker and there is less drag. On the other hand, apparently this craft has an IR camera to help it find thermals that it can ride to help reduce the power requirements.

That said, given the additional requirements of transporting a human, I give the award for most impressive achievement to the Solar Impulse team. Their pilot outweighs not only the payload of the AtlantikSolar and Zephyr crafts (0.8 kg and 2.5 kg, respectively), but probably also the whole UAV itself (6.8 kg/15lb and 53kg/117lb, respectively - I'll assume that their pilots don't have a second job as a jockey). Add to that about 5 pounds of food and 7 pounds of water/drinks *per day*, plus some bottled oxygen so the pilot can breathe at 40,000 feet... And apparently the sensor and data downlink package from Solar Impulse consumes up to 50W - that's as much as the craft in this article uses for all its needs, including propulsion. There's a lot of stuff required to keep us silly humans alive.

I'll grant them that it's an impressive feat in a small package - but I still think the bigger package with the bigger payload (a human) is more impressive.

Comment Re:Everyone makes $1,000,000 mistakes (Score 1) 377

SIX revisions? Hopefully only metal layers, or were some a full base spin too?

Where I work, we usually go into production on the second revision. Occasionally, the first one is good enough (usually if it's similar to a previous chip). The one I worked on most recently was a brand new design from the ground up with a new team of people, so we shipped the 3rd version (both spins were just metal layers). We (almost) never change the base layer - the case I heard about was when somebody in Marketing told someone in Engineering that there was no way they'd ever want to market a specific part to use >n MB of memory (probably 512 or so), because it was a low-end part. So they put enough address bits on the part for 512 MB - and then not too long after making it, Marketing decided that they needed a 1 GB version too. Then it just became a question of "is it worth a million dollars to be able to sell it with 1 GB?"

I'm in verification, so my whole job is to make sure we haven't made any million dollar mistakes. I produce no useful output, other than a thumbs up to management right before they start producing wafers. Some mistakes still get past us, but when a million dollars is on the line, some creative changes (often just in software) can help us keep the problem at bay.

And any time a big mistake gets by, another item gets added to our checklist. Being the first guy to make a particular mistake is usually professionally survivable; everybody makes mistakes sometimes. But being the second guy to make the same mistake does not bode well for your future...

Comment Re:This done right is a good thing. (Score 1) 130

My bank uses IP addresses as part of its algorithm, as a proxy for location. One of their security options is to only require 2-factor authentication when logging in from a new computer, or doing something suspicious (changing your contact information or wiring all your money to Russia, for example). It was reasonably convenient, but I eventually decided to go with the stronger security of always requiring 2FA.

The best thing you can do is probably to find a bank you trust. My local credit union is friendly, tech-savvy, and has decent rates. They also have far less of a 'screw the customer' attitude than some of the big banks. I've heard of some that will reorder all your withdrawals in a day before all your deposits to try and overdraw you so they can charge a fee. Mine does the opposite; all the deposits are processed first, so even if you do overdraw, you have a grace period until the end of the day. And at that point, you can still have an automatic overdraft transfer to protect you from being overdrawn by taking from another account, or you can have an automatic line of credit so that you only get charged interest instead of a big fee.

Comment Re: too many to list (Score 1) 258

I did that about 6 years ago myself. I had about 25 computers doing accelerated life testing of a chip in them, running it at elevated voltage and temperature to see if there were likely to be any reliability issues during the lifetime of the part. Unfortunately, one of the disadvantages of running a chip well beyond its rated specs is that sometimes it doesn't work - and it takes the rest of the computer down with it. So the computers would frequently write to a log file (one for each computer). I had a script running on my PC that, if a computer's log file hadn't been updated in about 5 minutes, would telnet to the appropriate IP power switch and toggle the appropriate outlet for the given computer. If that didn't work, it would try again in another 5 minutes. And if it failed 5 times in a row, it would send me an E-mail to go check it out manually (at that point, sometimes I'd find that capacitors had melted themselves off the board and embedded themselves in the floor wax below).

This same setup also had customized heatsinks - there was a fan mounted on the heatsink, and also a couple of resistive heaters attached with thermal epoxy. (I must be one of the few people in the history of the world to attach a heater to a heatsink to make the component underneath run hotter.) We had a custom controller that would monitor the temperature of the chip, and cycle the fan and heaters appropriately to maintain the target temperature. There were scripts that controlled both the voltage and temperature of the chip, but periodically dropped them down to nominal levels to run functional testing or (somewhat less often) to measure the speed of the chip, to see if it had degraded. It was a pretty nifty automated setup.

It had its bugs, though. It was DOS-based (since the diagnostic software for our chip ran in DOS), and apparently something in this version of DOS (or the computer it was running on) couldn't handle the time going past midnight; after 11:59 PM on June 3rd, it would go to saying 12:00 AM on... June 3rd. This made timekeeping rather difficult, so I had to add some logic to my scripts to determine if time ever went backwards - when it did, I knew that we must have passed midnight. The fix in that case was to have the computer reboot itself, at which point it would figure out that it was really June 4th, and time would continue marching onwards.

Comment Re:HP28C infrared input (Score 1) 258

And another not-exactly-a-hack-but-problem-solving-nonetheless...

When I was doing my Master's research, I wrote a program to do some optimization for me. I didn't have the forethought to allow it to save its progress, or to have it tell me how much progress it had made. Often when I ran the program, it would finish in a day or two. But one of the runs I did took well over a month to complete. It had already been running for 20 or 30 days, and the lease was expiring on my apartment. I didn't want to start the computation over (I was supposed to graduate within a month, if I had the data anyway). Luckily, I had my desktop hooked up to a UPS - but normally, that would only last for 10 or 15 minutes. Probably much less, given that the CPU was cranking away on my program.

So I disconnected the UPS's USB port so it couldn't communicate with the computer (normally, to wake it up so that it could be safely shut down), disconnected everything from it, and put the computer to sleep. Once my apartment had been emptied of all my belongings, I unplugged the UPS from the wall and carried the desktop and UPS together out to the car, then drove the van filled with all my possessions post haste to my parents' house, about 25 minutes away. The UPS was beeping the whole time to let me know that it had no AC power. Luckily, it still had some battery left when I got it plugged in, probably 40 minutes or so after unplugging it. I was then able to connect the monitor and everything else back up, wake the computer, and it kept on chugging for another week or two to get my results.

Comment Re:HP28C infrared input (Score 2) 258

That reminded me of something - maybe not really a hack per se, but some creative problem solving. I was at a Mac User Group meeting around 2000 or so, and somebody was supposed to do a presentation. Unfortunately, the presentation was on one laptop, and the projector was on another. Now, in many cases over many years, this is basically a non-issue - there are usually several ways to transfer files. Unfortunately, because of the laptops involved (maybe a PowerBook 5300 and a PowerBook G3?), the options were limited - they were on either side of a watershed in Apple's designs. They might have both had Ethernet, but we had no crossover cable (this was before Apple started making all their products do auto-crossover internally). They both had Infrared ports, but one was Apple's proprietary IRTalk protocol, and the other was the incompatible IrDA protocol. One had a serial port, the other had USB. One had a SCSI port, the other had FireWire. One had a floppy drive, the other had a CD-ROM.

Finally, we realized that we could hook a modem to both and set up a, well, I always thought it was called a null modem connection, but I just now discovered that's apparently something else - we connected one modem to the other with a single phone cable (no PSTN, no dial tone), and basically told one modem to "dial" and one modem to "answer", and we had our connection. (Maybe called a "dry line"? I can't find a good name for this with a quick search.) Then we just had to figure out how to FTP across that connection, and finally (close to an hour later, I think) we had the presentation on the computer that needed it.

"Confound these ancestors.... They've stolen our best ideas!" - Ben Jonson