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Comment: Re:It's not the PC microphone ... (Score 1) 62

by Ungrounded Lightning (#49177877) Attached to: Ask Slashdot: Wireless Microphone For Stand-up Meetings?

Or bypass the problem completely by using a USB microphone. These digitize the audio right next to the microphone proper, with everything floating at the same voltage so nothing substantial is picked up betwen the air pressure sensor and the A-D converter.

Bluetooth headsets work great for this, too. Most current generation laptops already have the bluetooth central-role radio onboard. Or get a cheap low-profile bluetooth dongle.

Comment: It's not the PC microphone ... (Score 1) 62

by Ungrounded Lightning (#49177857) Attached to: Ask Slashdot: Wireless Microphone For Stand-up Meetings?

4. PC/laptop microphones suck. I don't know why no one bothers to test them to the same level as your average cheap dumbphone speakerphone. They pick up all kinds of system electrical noise, ...

The problem usually isn't the microphone. It's the way it's wired (per the standard) and the way the desktop/laptop is powered.

PC microphones are wired UNbalanced: They have a signal and a ground wire, rather than the + and - signal wires and everything-but-desired-signal cancelation of the balanced wiring setups typical of professional microphones.

Laptops typically use power supplies that are not grounded, so they don't require a three-prong outlet. This usually ends up with the stray capacatance to BOTH sides of the line wiring capacitively coupling equally to the laptop "ground". That means the "ground" of the laptop is at half the line voltage - about 60 volts of AC (a rotten approximation of a sine wave plus lots of other junk it picked up at an assortment of frequencies). The capacitance is substantial - not enough to shock you if you touch the laptop and ground, but enough to feel a buzz if you rub your hand lightly across a "grounded" metallic part of the device.

Plug in the unblanced microphone and hold it, put the headset on your head, or just leave it sitting on the table. The "ground" is at 60V and you are driving maybe a couple MA of it down the shield wire. The voltage drop of that current (along with any other pickup) adds straight onto your audio input. The best microphone in the world will perform horribly if hooked up this way.

Try this: Unplug the laptop and let it run on battery. Notice how almost all of the noise disappears. You can also get rid of most of the noise by tying a decent ground onto the laptop. (Unfortunately, many meetings last longer than the laptop batteries...)

Plug in a VGA monitor with a three-prog power plug, which grounds the case of the laptop via the shield and the two hold-in screwd. I've done that without actually hooking up the monitor (which would have disabled my laptop screen) by adding a couple of the nuts scavenged from another DB connector as conductive spacers so the actual signal pins are not quite into the plug. And done this on a docking station, so the laptop headset was quieted when the laptop was docked, even though I used none of the docking station features except the power input.

Make a second cable with a three-prong plug to bring a ground up to the laptop. Green wire from the third pin to a screw into or clip onto such a chassis ground point.

Or bypass the problem completely by using a USB microphone. These digitize the audio right next to the microphone proper, with everything floating at the same voltage so nothing substantial is picked up betwen the air pressure sensor and the A-D converter.

Comment: Re:Why is Israel not part of the NNPT? (Score 1) 52

by Ungrounded Lightning (#49167501) Attached to: Interactive Edition of the Nuclear Notebook

Because they didn't sign it.

Saying: "everyone who has them except Israel is allowed to keep them" is just plain wrong.

Which just might be why they didn't sign on - and part of why "Israel has had a policy of opacity regarding its nuclear weapons program."

Some things to remember about the NNPT:
  - Not every country in the world is a signatory.
  - Even signatories didn't permanently give up their right to develop nuclear weapons: By the treaty's own terms (section X(1)), they can drop out on three month's notice:

Article X

1. Each Party shall in exercising its national sovereignty have the right to withdraw from the Treaty if it decides that extraordinary events, related to the subject matter of this Treaty, have jeopardized the supreme interests of its country. It shall give notice of such withdrawal to all other Parties to the Treaty and to the United Nations Security Council three months in advance. Such notice shall include a statement of the extraordinary events it regards as having jeopardized its supreme interests.

Comment: But it WILL dry some of them out... (Score 2) 184

by Ungrounded Lightning (#49167191) Attached to: World's First Lagoon Power Plants Unveiled In UK

Bonus points: it wont flood any place in land that is not actually flooded twice a day,

But, by retarding the tidal current, it WILL dry out part of the area currently intermittently wetted, and WILL keep continuously wet another part of it that is currently intermittently dried.

Comment: Wonder how they'll rate Global Warming discussions (Score 1) 371

by Ungrounded Lightning (#49162031) Attached to: Google Wants To Rank Websites Based On Facts Not Links

... when there is more than one version of the truth (conflicts, spin vs fact)... plus not all information is facts... philosophical questions may have more than one answer etc... so I am definitely curious to see how this works out.

I'm curious as well.

In particular, I wonder how they'll handle Global Warming / Climate Change discussions.

Then there's electoral politics, economics, Illegal immigration / undocumented migrants, ...

Comparing to a knowlege base presupposes that the knowledge base is full of truth. Filtering search results to exclude (or down-rate) anything at odds with the current paradigm is a recipe for hamstriging research, debate, and intellectual progress

  Ideas need to be supported or rejected based on evidence and logic, not whether they're orthodox.

Comment: Re:Or the malware might cover its tracks. (Score 1) 310

by Ungrounded Lightning (#49161967) Attached to: Ask Slashdot: How Does One Verify Hard Drive Firmware?

I mean if they go to the trouble to do this why do it in a way that would be discoverable via jtag for other state actors. I mean if they go to the trouble to do this why do it in a way that would be discoverable via jtag for other state actors.

Because hacking the JTAG to hide malicious hacking of the software is a massive endeavor and a massive PITA.

Besides, if they built it into the original software they wouldn't NEED to hack the JTAG to hide it. The code would match the released version. (You'd have to reverse-engineer it to discover their back doors.)

Comment: Or the malware might cover its tracks. (Score 1) 310

by Ungrounded Lightning (#49158963) Attached to: Ask Slashdot: How Does One Verify Hard Drive Firmware?

If you ask the drive to read out the whole flash.
The maybe the firmware would have to go to the platter to get the real image.

Or the malware could regenerate the un-attacked version.

For instance: If it's a patch that loads into an otherwise cleared-to-known-vallue region it can detect that region while reporting flash content and report the cleared value, instead. Add a couple other tiny regions where it saved (or alread knew) the previous contents where it "sank it's hooks" and you can't tell it's there from its replies to dump requests.

JTAG seems safer.

Yep. JTAG, in principle, could be corrupted. But it would require substantial hardware support that almost certainly isn't there (yet!)

Comment: Hashes can be useful. (Score 1) 310

by Ungrounded Lightning (#49158915) Attached to: Ask Slashdot: How Does One Verify Hard Drive Firmware?

Which is why I always laugh my ass off at all these people who use PGP to sign things and put a hash on the same website you download it from ... look you can verify this file you downloaded from the website hasn't changed because theres no way anyone would be smart enough to update the hash as well!

That's why you SIGN the hash. Then only the public key needs to be published by a different route.

And it doesn't HURT to publish it on the web site as well: Then someone tampering by substituting a different public key sets off alarm bells when that differs from the public key obtained from another site or by another path. Blocking that makes man-in-the-middle more complex: The attacker has to have essentially total control of the path to the victim and be able to recognize and substitute the public key whenever it shows up. One slip-up and somebody may raise the alarm.

Meanwhile: Even if publishing hashes on the same site may not provide additional security against MITM, it DOES let you check the download wasnt corrupted in transit (in ways other than malicious substitution). With modern protocols that's less of a problem these days than it used to be, but a check would be comforting.

Comment: Re: stop the pseudo-scientific bullshit (Score 1) 87

by jd (#49156217) Attached to: Mysterious Siberian Crater Is Just One of Many

The Great Extinction, caused by Siberia becoming one gigantic lava bed (probably after an asteroid strike), was a bit further back in time. Geologically, Siberia is old. You might be confusing the vestiges of Ice Age dessication (which was 10,000 years ago) but which involves the organics on the surface with the geology (aka rocks).

Regardless, though, of how the craters are forming, the fact remains that an awful lot of greenhouse gas is being pumped into the air, an awful lot of information on early civilization is being blasted out of existence, and a lot of locals are finding that the land has suddenly become deadly.

The degree of technical confidence is inversely proportional to the level of management.

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