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Comment: Re:Call me an old guy with a short attention span (Score 2) 85

by langelgjm (#49378661) Attached to: No Film At 11: the Case For the Less-Video-Is-More MOOC
Just took a Stanford MOOC on statistical learning. The best part of the course was the PDF textbook that the authors made available free of charge. The videos served to reinforce what I had already read in the textbook, and were by no means a substitute for actually reading the book. But I did appreciate them.

Comment: Re:We aready have this (Score 1) 32

by langelgjm (#49378563) Attached to: Hand-Drawn and Inkjet Printed Circuits for the Masses (Video)

Yeah, soldering SMT is not that hard, at least for the larger packages and pitches. The no-lead stuff is hard without specialized tools, but with a decent iron, flux, good light, and a loupe you can accomplish a lot.

My strategy is to prototype on a breadboard, and use breakout boards for the SMT components. Then when the design has been thoroughly tested, design a PCB that either accepts the larger SMT stuff directly, or accepts the breakout boards. Requires lots of care in design, and all my projects have been relatively simple, but if you're patient, the result is good and not very expensive.

I've tried the print and etch process, but the pitches you can achieve are not small enough to make it worthwhile for me. The whole point of getting away from perfboard was to use SMT, and in my experience it's too easy to mess up small traces when etching at home.

Comment: What is a "cyberattack"? (Score 4, Insightful) 58

The article doesn't say. A ping flood? Attempted DOS? Attempt to connect to telnet port?

Sorry, but this guy is clearly exaggerating the number in order to try and get more money. Kind of like when Darryl on The Office wrote on his resume that he had overseen the "shipping of 2.5 billion units of paper material." I.e., pieces of paper.

Comment: National Cryptologic Museum was different (Score 4, Interesting) 121

by langelgjm (#48978973) Attached to: Alan Turing's Notes Found After Being Used As Insulation At Bletchley Park
Visited the National Cryptologic Museum (on the same campus as the NSA, just off 295 in Maryland) about a decade ago. I and my then-girlfriend were probably the only visitors in the entire building, and the staff were pretty excited to see us. They even let us try out the German Enigma machine they had on display - no glass display case at that time! Don't know if it's changed in the last ten years, though.

Comment: Re:Not that easy to see (Score 1) 53

by langelgjm (#48885255) Attached to: Rare Astronomical Event Will See Triple Moon Shadows On Jupiter
I have a run-of-the-mill Tasco telescope and was able to make out the Galilean moons, as well as two cloud bands on Jupiter, and of course Saturn's rings. The big challenge I had was damping vibration - any touch of the telescope or the stand would make the image blurry. You can even make out the Galilean moons with binoculars.

Comment: Will new firms last long enough to pay claims? (Score 0) 238

by langelgjm (#48858267) Attached to: Google Thinks the Insurance Industry May Be Ripe For Disruption
No doubt the industry is ripe for disruption. BUT in addition to risk measurement, another big part of insurance is the stability of the insurer, especially with long-term insurance like life insurance. How confident are you that the Uber of insurance will be around when you die 29 years into your 30-year term life insurance policy? Or will they have been acquired a dozen times by companies of varying financial strength?

Comment: Re:Arduinos and MCUs (Score 2) 189

by langelgjm (#48776719) Attached to: Ask Slashdot: Options For Cheap Home Automation?

Some of the ideas seem like they could be solved by off the shelf hardware. Switching loads based on temperature? Buy a cheap programmable thermostat. If you want to monitor an AC load, you can use your preferred microcontroller along with an opto-coupler. I just did this, using an opto-coupler to monitor my programmable thermostat's relay and report a logic level to a Raspberry Pi, which then logs when the relay is closed (and thus the heat running) versus open (heat off). You can get opto-couplers that include built-in rectifiers, allowing you to work with AC voltages, but of course you need to understand what you are doing to avoid danger.

I used an Electric Imp, which is a WiFi-enabled microcontroller, hooked up to a digital temperature sensor and a photoresistor, as an outdoor temperature/daylight logger. Electric Imp is a hosted solution, which is not ideal - unless someone else reverse engineers the protocol and builds their own server, when the hosted service disappears, it'll be worthless, but it was very easy to use. Here's a graph of the output.

Cost becomes an issue. WiFi connectivity is expensive. Cheapest I think you can do is about $25 - that's what an Electric IMP costs (not including a breakout board), or a Raspberry Pi A+ if you throw in a $5 WiFi USB dongle. So you're looking at a minimum of $25 for each WiFi enabled device (and neither of those are ideal - Imp is hosted and lacks much GPIO, PI is large, delicate, and lacks some basic microcontroller features). That's not very affordable, especially if you're used to throwing a $3 Atmel chip in your devices.

My thinking going forward is to couple Arduinos with relatively inexpensive RF transceivers that work in the ISM band, and simply use one WiFi device (like the Pi) as a base station that can talk to all the other devices. That will bring the cost-per-unit down to maybe $15.

Note that you will be spending a LOT of time on each project. And you will almost certainly spend far more money than you will ever save. But we do it for fun, not for efficiency!

Comment: NASA Spinoff (Score 2) 287

by langelgjm (#48744683) Attached to: Should We Be Content With Our Paltry Space Program?

Vague statements about technological advances probably won't cut it either. Of the small percentage of people who actually care about general technological advanced, an even smaller percentage are convinced it's best done through dangerous and expensive space programs.

A friend of mine works for a contractor that produces NASA's "Spinoff" publication, which highlights the broad contributions from NASA research and programs: Several of us were ribbing him about how NASA does a pretty bad job of publicizing the publication designed to showcase its public benefits.

Comment: Just replace your thermostat. It's easy. (Score 2) 252

by langelgjm (#48735957) Attached to: The Missing Piece of the Smart Home Revolution: The Operating System

"We turned your thermostat up to 85 degrees and you can't change it. We want $5000 worth of Bitcoins in 72 hours--or we find out if your furnace perpetually on full-blast will burn your house down.

You do realize that virtually all consumer thermostats use a fairly standard interface, and they can be swapped with one another, right? This includes the Nest/Ecobee, etc. If someone threatened me like that, I'd laugh at them, disconnect the thermostat from the wall, and attach a cheap replacement.

Comment: XML is being generous (Score 4, Informative) 32

by langelgjm (#48676811) Attached to: Net Neutrality Comments Overtaxed FCC's System
Having looked at the XML files they provided, while some are marginally useful, about 1.4 million reply comments are simply dumped into CDATA sections without any consistent formatting or separators. After much regex splitting, it was readily apparent that the downloads they provided were missing about 700k comments. Glad to see they're actually admitting it and may even remedy it.

Comment: Re:Weird article (Score 1) 177

by langelgjm (#48618729) Attached to: Army To Launch Spy Blimp Over Maryland

I doubt it as its intended to track flying things. This data is already available from multiple sources.

The article mentions several times that it can be used to track cars, trucks, and boats. Obviously we have data from lots of interstate monitoring stations, as well as devices to measure the amount of traffic passing specific points, but I'm not so sure we have such detailed data across such a wide swath of territory (multiple states) that could actually track object movements (rather than, say, just a count of vehicles passing a point). Maybe someone who knows better can chime in.

An inclined plane is a slope up. -- Willard Espy, "An Almanac of Words at Play"