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Comment Electromagnetic Immunity (Score 5, Interesting) 173

I get to deal with weird stuff like this at work all the time. Based on the behavior, I'd guess there's a clock and/or data running at a harmonic of the wifi data. Freezing seems to indicate it's coupling into the core of the LCD controller board, which again I would guess is a timing violation or data corruption. Where it's coupling in is a bit hard to determine without further testing. It could be the video cable, could be the power cable (not likely), could be the LCD panel itself acting as an antenna, or an interconnect cable that is poorly shielded or just the right length to couple in wifi. It could also be power supply ripple caused by a feedback loop getting energy coupled in, though if that's possible then there's not enough timing margin to begin with.

I suggest a number of tests to narrow down details of the source:
- Test 2.4GHz and 5GHz independently. Test each wifi channel independently.
- Try a different length cable. Try a different brand cable. Does this monitor remain on with nothing connected? If so then try it with no cable, or no PC at the end.
- Try different antenna angles. Try different TX power levels (at what level does it start).
https://tech.slashdot.org/stor...
Based on those results I'd have more recommendations.

If someone wants the real root cause, feel free to send me one and I'll debug it (though it will probably require disassembly).

Comment Race Conditions (Score 1) 230

Reminds me of debugging errors related to digital logic race conditions. When you are on the edge of meeting timing, a slight shift in the wrong direction can cause the result to be incorrect, sometimes with an order of randomness. Until you violate that timing you have the feeling of security since everything is going smoothly. I'm sure there's a more mathematical way to explain this, but similarly I think much more testing could be done to understand what variables effect the outcome. It would be interesting to see more details, such as how many pixels must be modified for a failure? To what magnitude do the pixels have to be changed by? Is there a tradeoff between # of pixels and magnitude of change per pixel? Are certain pixels more important than others (edge detection for example)?

Submission + - Apple A4 Processor Teardown (eetimes.com)

Plocmstart writes: Here's what EETimes.com is claiming to be the first teardown of the A4 processor. "Apple's iPad chip is a single-core ARM A8 made by Samsung. Through various benchmarking testing, UBM TechInsights was able to find out the details of the A4 processor."

Submission + - Buckeye Bullet 2 sets the record for fastest hyrdo (buckeyebullet.com)

Plocmstart writes: "The Buckeye Bullet 2 has set the record for the world's fastest hydrogen fuel cell vehicle at 302.877mph. The vehicle was designed and built a team of engineering students at the Ohio State University. The Buckeye Bullet 1, an electric battery-powered vehicle, also holds the international record for the fastest electric vehicle at 271mph (top speed 321mph)."
Idle

Submission + - Klingon keyboard a reality

Plocmstart writes: 'ZF Electronics UK — formerly Cherry Electrical Products UK — is delighted to have been persuaded to turn what was originally conceived as a marketing gimmick into a real product. Last year the company announced the Klingon keyboard — as a spoof to demonstrate its capabilities in producing keyboards with non-standard language layouts including Hungarian, Kazakhstan, Maltese and Faroese (Faroe Islands). However, due to a number of serious enquires, the company has produced a fully functional keyboard with Klingon characters which works with PCs running Windows, OS-X (Mac) or Linux... '

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