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Comment Re:What bugs me about USB power (Score 1) 152

IMHO: A USB device that depends on its power source to limit its input current, and can be damaged by a host that is willing to deliver more current that it requested, is defective by design.

Current limiting is to protect the supplier of the current. Bad current negotiation can damage the power supply, so of course the power supply should limit the current. A bad power supply may break, though. I think the main problem is that USB-C can use a range of voltages and a 5 V device plugged into a 20 V power supply will blow up the device unless the 20 V supply is signaled to throttle back to 5 V.

But maybe I misunderstand. Unfortunately, the reporting about this topic (Leung's findings) is very fuzzy about what happens exactly. But I don't see any scenario where connecting a good quality 5V, 1A or 2A charger to any USB-C device can lead to damage.

Comment Re:I Stopped Using Custom ROMs (Score 1) 215

"your uncommon hardware may get burned out early (I've lost many wifi / gps / bluetooth / 3g-4g chipsets that way)."

This is the first time I hear smt like this. Do you have evidence?

The gps radio in my nexus 5 (with CM) tends to deteriorate over the months, but it turned out that tightening the screws of the rf shield restores the reception. Not a software issue.

Submission + - WhatsApp encryption back door ( 1

siloko writes: From the article: "A security backdoor that can be used to allow Facebook and others to intercept and read encrypted messages has been found within its WhatsApp messaging service."

Comment Re:Is this theoretical? (Score 1) 207

A modern dac is supposed to digitally filter at 20 kHz (very hard cutoff), in exchange for lots of noise above 100 kHz. A soft roll-off analog filter takes care of the content above 100 kHz.

I suspect that ultrasound in this context really means 16 kHz or so, at volumes that are too low for the ear, but easily picked up by a microohone and some signal processing.

Comment Re:Is this theoretical? (Score 1) 207

What kind of audio source did you use to find that you can hear 22 kHz? Unless you have an ultra low noise analog sine wave generator and amplifier, you are likely to hear noise, artifacts of the DA converter, and effects of clipping when you crank up the volume. The stated limit of 20 kHz for the human ear is the frequency where the pain threshold and the hearing threshold coincide for an average young person, so it is likely that you need >110 dB SPL to have any chance of hearing above 20 kHz. A device with 90 dB S/N ratio will likely blast you with lower frequencies, which you could easily mistake for "I can hear 20+ kHz".

I did once fry the tweeters of my (60 watt rated) loudspeakers while trying to test the limits of my hearing as I was sending all amplifier output power to the tweeters.

Comment Re:Battery life is not the real issue (Score 1) 254

Although the general point is probably correct that min/max charge levels affect Li-ion lifespan, I would be careful with using batteryuniversity as a source of information. It's really a weblog of a small manufacturer of battery chargers that presents a couple of small-scale test results as if they represent the absolute truth for all brands and types of Li-ion batteties.

Comment Re:T-mobile appealing, continuing practice (Score 1) 61

Until a music-streaming provider complains about being discriminated against, I don't think the review of the whitelist is the problem. The legal issue seems to be about the question whether discrimination by type of content (music, in this case), regardless of the company that provides the content, is allowed or not.

My feeling is that T-mobile is in a weak position here. Because if T-mobile is right, they would also be allowed to discriminate against other types of content; for example by making VoIP traffic more expensive. In fact, this is already happening: the cost of any data traffic is increased to subsidize the bandwidth for music data.

Comment T-mobile appealing, continuing practice (Score 2) 61

Spotify, mentioned in the summary, is a bad example, since it is one of the many streaming services that is whitelisted. T-mobile allows any streaming provider such as spotify to sign up, without restriction or charges. According to T-mobile, this is allowed by the European law, which takes precedence over Dutch law. So, they are appealing in court and continuing their service for the time being.

References (Dutch, you'll have to pass it through Google Translate):

Comment Re: better options (Score 1) 50

"I've yet to hear a reason why removable batteries are a bad thing for consumers with the sole exception of anorexia."

I used to have an HTC Desire S, with removable battery. A drop from 5 cm with the wrong angle would temporarily disconnect the battery, leading to a power-off. I had to put in a spacer to push the battery harder against the spring contact. (it took quite a while to figure out what the problem was)

I have a low-end LG L40 with removable battery. Every time I drop the phone, the back cover will come off and I end up with a separate battery, cover, and front. At least it immediately removed its own battery when I dropped it in the toilet. (phone is still working after a rinse in distilled water and thorough drying)

And I have a Nexus 5 with "non-removable" battery. The back cover can still come off with some effort; the battery can be replaced although it's a bit more work. And I don't have the above problems with self-disassembly and flaky contacts.

I'll take the "nonremovable" battery, thank you.

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