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Comment Re:I can't make much of it. (Score 3, Interesting) 64

On some Dell tower PC's from around 2008, the notification was that at the next boot, the BIOS firmware showed a message saying something like "A single bit memory error was detected and corrected, press F1 to continue."

I have some sticks of RAM (in a box of junk somewhere) that caused the message on the hottest days of the year.

Comment Re:Reminds me of old FM radios (Score 3, Interesting) 87

That worked because receivers made before about 2010 all converted the desired station down to 10.7MHz using a local oscillator signal.

The local oscillator frequency can be 10.7MHz above or below the desired frequency so the effect is different between different models of radio.

The local oscillator signal leaked out of the radio very weakly but enough to be picked up on another radio a few feet away.

These days most of the crappy ten-dollar domestic radio receivers use a single chip silicon tuner. They have a couple of chips on a circuit board, they don't contain a load of coils, capacitors and tuning cans like old radios.

Silicon-tuner radios have much lower LO leakage because the signal generation circuitry is in a tiny silicon chip.

Comment bitlocker from new (Score 4, Informative) 207

It is now common for laptops to be shipped with the harddrive/ssd encrypted with bitlocker. Many people are unaware of it.

If you don't create a Microsoft account then later if the laptop goes wrong and won't boot you can't access your files by connecting the harddrive or ssd to another machine. Without a Microsoft account you can't get the bitlocker key.

If a laptop with bitlocker boots to a login screen then the bitlocker key has to be stored in the laptop, in which case it can be obtained by soldering wires to the I2C bus and using a logic analyzer. It is way beyond the technical ability of the average person but can be done.

To mitigate that, some corporate laptops are set up to erase the TPM if the laptop case is opened. You opened such a laptop to add more RAM and can't access the email that was used for the Microsoft account?, any files you didn't back up separately are gone forever.

Comment Windows ME active desktop (Score 1) 269

My main memory of windows ME is a mostly white screen with some text that said "Active Desktop Recovery".

I never knew was active desktop was supposed to do and usually had applications open full-screen covering the desktop. It was just this thing that had always crashed in the background after the computer had been on for an hour or two.

Comment starlink Russia (Score 1) 171

Using Starlink in Russia would be operating a radio transmitter without a license, or a license exemption, so they already have laws covering this.

Currently Starlink requires a ground station with a fiber internet connection that is located within about forty miles of the users (depending on local terrain such as mountains in the way).

Russia is big, currently Starlink could only cover small parts of Russia near the borders if a ground station is set up in a neighbouring country.

The satellites are in a low orbit so are only visible above the horizon from a smallish area of the earths surface. Customers only get internet when a satellite is directly in view of both the customer and a ground station.

The long term plan is for laser links between satellites. That is required for coverage out in the oceans or in countries where ground stations can't be set up (perhaps such as countries where the USA is at war so the military might want to use starlink without regard for local laws).

Starlink is reported to be far from getting laser links between satellites to work. As far as I can tell from a bit of reading, current Starlink satellites don't have hardware for laser links.

Comment Oneweb positioning system practicality (Score 2) 80

It seems very impractical to me.

Current satellite positioning systems require three satellites in view in the sky. In theory, it can be done with two if the receiver on the ground has a source of timing with the stability of an atomic clock.

The current 31 operational GPS satellites are at an altitude of 20000Km

The Oneweb satellites are at an altitude of 1200Km. They are in view above the horizon from a much much smaller area of the earths surface.

If they want enough satellites for it to work to be in view most of the time then thousands of satellites would be needed, each carrying an atomic clock, and ground stations have to track the satellites with sufficient accuracy to predict the orbits with an accuracy of centimetres. I suspect that is a bit more difficult for a low orbit where there are a few air molecules and greater variation in gravitational force.

It seems to me that Oneweb does not have anywhere near enough money to make a system to supply internet from the sky that can complete with starlink.

Comment Re:Where did get this idea (Score 2) 108

The problem is that keys used today are weak - and the ones used in the past even weaker.

In 2030 it will be trivial for a nation state to forge an email sent in 2020 that matches today's DKIM, and for a bedroom hacker to do it for an email sent in 2010.

Encryption that we tend to use is good enough for now - but not for 20 years time. In the 2032 election when Donald Jr is dukeing it out with Ocasio-Cortez, it will be easy for Russia, China, Nigeria, or probably even 4chan, to fake some SKIM signed emails from 2016 showing they actually planned to secretly take over the country in a Kang vs Kodos way.

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