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Comment Needn't be done on the power company's premisis. (Score 1) 109

How hard would it be to send signals from the power plant or substations across different parts of the grid creating a signature that could be detected in recorded hums?

It wouldn't have to come from the substations. It could be injected at any power feed (though the higher-capacity feed the better). B-b

It might also drive the power company nuts - especially if it was close to the line frequency, because that would look like a large and rapidly varying power factor.

Comment Re:Well, sort of. (Score 1) 109

I've been trying to think of how there could possibly be enough variation to fingerprint someone based on the hum caused by that 60Hz frequency noise. I've been in transmission control centers where they monitor, regulate and occasionally wet themselves over frequency shifts, and I've seen that the amount of variation needed to cause sheer panic is shockingly low..and it rarely ever happens for even a second. And those tolerances have been the same everywhere I've gone.

The frequency is synchronized across the whole grid.

The phase shifts, due to several factors (which way the power is going on the lines (treated as signal transmission lines), power factors of loads switching on and off, etc.) Much of this shiftig is local (motors on your transformer starting and stopping, etc.). Some of it is regional (for starters: the average across a distribution block of all those motor loads switching).

The combining of the varioius contributibutions to the phase offset is essentially linear. So if you have a recording system that is including power line hum and sufficiently stable on a tens-of-seconds time scale, the phase can be extracted and correlated with a recording from a nearby part of the grid. The closer they are (in electrical term), the stronger the correlation.

I could imagine the NSA recording this phase signal from one or several places in each city or rural region and archiving it, then using a cross-correlation against such a signal extracted from a recording. The amount of data to be stored and processed would be pretty small and a hit would stand out like a beacon.

First run against a national average (or several regional signals) to get enough of a hit to identiy the time of the recording. Then run against that time segment of the whole database of local samples to get a rough location. (With enough samples this should get you down to a "which cell tower" level.) Then see what suitable recording studios are in the identified region and look for other clues.

Possible countermeasures:
  - Notch-filter out the power line frequency and its first few harmonics.
  - Bandpass filter out the low part of the audio.
  - Add in a small amount of hum of your own, with a pseudo-random phase jitter (and still more phase jitter on the harmonics). Be sure to use a set of pseudo-random generator that they won't be able to identify and cancel out - like by using several of them to continuously adjust the amount of phase noise added and such.
  - Jitter the sampling rate.
  - Re-record it with deliberate injection of a larger amount of real power line hum at a different time and location, before releasing the recording. B-)

Identifying edits in a recording consists of lookinf for a gross jump in the phase of the hum. Identifying the recording location from the pattern of small phase shifts (and other artifacts) in the power line signal is a much signal to find in a much larger amount of noise. I'm not convinced yet how doable it is. But with the above description of what I think they're doing, I expect a bunch of slashdotters will soon be playing with their audio cards, hacking up code to analyze recordings. B-)

Comment Re:The problem with Bitcoin (Score 1) 115

I think that Amazon and others love BTC simply because they dont have to pay a tithe to credit card companies

That's only true if they operate their own exchange - otherwise they're paying exchange fees. (Which admittedly are likely far lower than what they pay the credit card companies.)
 

but credit card companies help us deal with fraud, bad products, identity theft, etc. If you pay your credit cards off in time you get a company that can be helpful in dealing with fraud and identity theft vs nothing.

BTC is like walking around with krugerrands and bearer bonds without security.

This. And also the reason I refer to BTC as "casino tokens" rather than "cash money".

Comment Re:Myths are socially hilarious (Score 1) 198

To be fair, in the domain of common experience a 7' tall ape man living in the pacific northwest *is* far less crazy than the idea of a subatomic particle being in two places at once.

Good point, and one many of the /. types often forget.
 

There's this great book

But here... here you come off the rails. How about not acting like a creepy religious zealot who must witness and prosthelytize and lead people to the Light?

Comment Re:Waste of Tech (Score 1) 66

Ever wonder why, after almost a century of technological development, a lot of small time and hobby farmers still drive 1940's era tractors?

Because they're either dead broke, stupid, or they're fascinated by retro things. 1940's era tractors are uncomfortable, low power, and at best middling in reliability. (And while you can with ever increasing investment of man hours jerry rig them along, you can't get parts for them anywhere but on the (expensive) hobbyist market.) Just as with cars and most other things, anyone who can afford better has long since moved onto better.

United States

White House May Name Patent Reform Opponent As New Head of Patent Office 211

An anonymous reader writes The Obama Administration is set to appoint Phil Johnson, a pharmaceutical industry executive, as the next Director of the United States Patent and Trademark Office, according to sources. The move is likely to anger patent reform advocates given Johnson's past efforts to block legislation aimed at reining in patent trolls, and in light of his positions that appear to contradict the White House's professed goal of fixing the patent system. The top job at the Patent Office has been vacant for around 18-months since the departure of previous director David Kappos in early 2013. Currently, the office is being managed by former Googler Michelle Lee, who was appointed deputy director in December. Earlier this month, Republican Senators led by Orrin Hatch (R-UT) sent a letter to President Obama that praised Lee but that also described the current USPTO management structure as "unfair, untenable and unacceptable for our country's intellectual property agency."

Comment Re:What else have they gotten wrong? (Score 1) 37

That was my thought too... Nineteen pages of the size shown in the pictures is pretty much nothing compared to a complete set of diagrams. It's like getting nineteen pages out of Game of Thrones (which is itself just one volume of a much larger series). If they found errors with so little new information, it does not give me much confidence that their recreation is accurate to any great degree. (Especially given that they tossed out an approach now known to be the one used.)

Comment Re:Google Cardboard (Score 1) 198

Turning it on its side and putting it into the Google Cardboard (or similar) stereoptic holder gives you about a 1440x1250 display per eye. Looks right to me.

Now if (as I suggested in the Cardboard item) they installed two cameras on the phone back, separated by about eye distance, you'd have a camera that could take and display stereoptic pictures and/or do augmented reality without losing the scene's depth.

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