The last time there was cable and gas pipe damage in the Baltic, it took about two weeks for the investigators to do their thing and hold a press briefing. Some details ("mechanical damage, doesn't look like an explosion") had been published before, but most of the investigation results were publicized all at once.
What is publicly known this time: when and where the cables were cut (locations approximately, times accurately), and that there's a Chinese ship (Yi Peng 3) that was followed by Danish navy vessels, and the ship has been anchored for a week with constant guard from German and Danish (and possibly Swedish) navy.
There's a video[1] by a Finnish sea captain with MarineTraffic history access going over the track of YP3. Since it's in Finnish, a brief summary (or try your luck with auto-translation):
1) The ship sets off with a speed of 9-10 knots, but then slows down to 5-6 knots for 400 km or so, before returning to 9-10 knots. While weather could be a factor, other ships in the area experience no slowdowns.
2) The ship crosses the cables right around the reported break times.
3) There is an additional slowdown to 3-4 knots near a known underwater sand ridge.
4) The ships heading jumps around a bit; again, the other ships do not do this.
5) There is a missing portion in AIS data; however, this is seen with other ships as well.
Now, this is all circumstantial evidence, but is consistent with dragging the anchor on the seafloor for an extended period of time. Calling it sabotage would require establishing malicious intent, of course.
I don't buy that number (no source is attributed to it), or rather, I don't believe there's a single incident causing this.
The C-Lion1 cable is predominantly North-East - South-West whereas the BCS cable is NW-SE. They do meet, but the C-Lion1 operator Cinia says their cable broke about 700 km from Helsinki, east of the southern tip of the Öland island. That's easily over 150 km south from where the cables meet.
Also, C-Lion1 was reported broken at 4m, and the BCS cable at 10am the previous day.
New New Polar Bear (the Nov 2023 case) was definitely sailing down the Gulf with its anchor down. Estonian defense minister stated at the time there are drag tracks in the seabed for "over 185 km".
Not as dangerous as a stove, but the Xbox One had a capacitive on-off button. Turns out the dog could turn it off just by his fur touching it when walking by it.
First of all, the pilot is only required for decoding stereo and RDS. Mono FM does not use a pilot, so obviously there had to be a way to detect FM before stereo came along. I linked to a few of the approaches in a sibling (cousin?) comment.
Second, the pilot is embedded in the decoded FM audio. You need to demodulate FM to get to it in the first place. If you look at the waterfall display in an SDR receiver, it might seem like the signal is already present in the original radio frequencies (especially during silent periods), but it's there only indirectly.
If you have silence in an FM transmission (say 96.6 MHz), the only audio component present is the 19 kHz pilot signal, which causes the FM radio signal frequency to vary between 96.6 MHz ± k*19 kHz (not sure what's the value for k, but it's not 1). The sine likes to spend most of the time near the extreme values of its range; plot a histogram of a sine wave and you'll see peaks on either end.
The waterfall is basically a histogram over frequencies so it gets those peaks as streaks on both sides of the main carrier frequency (plus smaller ones for other components in the signal).
The 19 KHz pilot tone is interesting: it's not filtered out and is often reproduced by the speakers if you have good ones. You can verify this by using an audio spectrum analyzer application on your phone.
I've wondered if FM stereo drives pets nuts with its constant high-pitched tone.
You're right -- after reading some of the peer responses, I realized that (I think...) my response is just how the Broadcast FM signal modulates the parts of the signal, and not how it actually 'locks on'. I'm still learning!
I got an RTL-SDR this summer and brushed up my DSP skills playing with FM signals. PLLs are marvellous beasts; you can do a slapdash job in "designing" one and it'll still probably lock on just fine. Might not be optimal but will still lock.
Another fun one, when you have IQ samples, is the polar discriminator: calculate x[t] * x*[t-1] where x* is the complex conjugate, and take the angle with arctan. Feels a bit like magic ("is that all?") but is justified by the theory.
The photoelectric effect was known before Einstein, so the award was for theoretical achievements. (But only after Millikan had done precision measurements on it)
Haven't built a house, but some indoor construction notes:
Measurements are specified in mm, yes. How well they're adhered to depends on the application.
Factory-made kitchen cabinets, for example, are usually 600 mm wide, and this is pretty spot on (and since it's chipboard it won't warp much). The doors are specified a few mm under, so 597 mm for example.
Drywall comes in at 1200 mm; again, this is quite accurate. The studs then go on a convenient fraction, usually either 400 mm or 600 mm. However, there's much more leeway in precision since you don't see the studs once the wall is up.
And yes, seals and caulking and floor molding and other such tricks are used to cover up gaps where necessary.
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Personal anecdote: we recently got new a new fridge and a new freezer. I'd made measurements of the installation location (1200 mm), checked the appliance widths (595 mm), and figure it'd be tight but doable. Turns out the wall was slightly crooked, and I'd measured it near its widest location. Ended up cutting out the (chipboard) wall on one side.
What I think is funny is that lumber and carpentry over there are done in units of 300mm for exactly the same reason we use 12 inches per foot: divisibility. Divisibility by 10 is useless for these types of projects, but divisibility by 3 and 4 are not!. And 300mm is just another name for the foot. You say that you’re using metric, but you’re really not. Your ancestors just uselessly multiplied all the numbers by 25.
Oh and in Finland there's a separate per-kWh fee to the local electricity network operator for transferring the electricity, so the breakeven point is somewhere around -4 c/kWh.
What is publicly known this time: when and where the cables were cut (locations approximately, times accurately), and that there's a Chinese ship (Yi Peng 3) that was followed by Danish navy vessels, and the ship has been anchored for a week with constant guard from German and Danish (and possibly Swedish) navy.
There's a video[1] by a Finnish sea captain with MarineTraffic history access going over the track of YP3. Since it's in Finnish, a brief summary (or try your luck with auto-translation):
1) The ship sets off with a speed of 9-10 knots, but then slows down to 5-6 knots for 400 km or so, before returning to 9-10 knots. While weather could be a factor, other ships in the area experience no slowdowns. 2) The ship crosses the cables right around the reported break times. 3) There is an additional slowdown to 3-4 knots near a known underwater sand ridge. 4) The ships heading jumps around a bit; again, the other ships do not do this. 5) There is a missing portion in AIS data; however, this is seen with other ships as well.
Now, this is all circumstantial evidence, but is consistent with dragging the anchor on the seafloor for an extended period of time. Calling it sabotage would require establishing malicious intent, of course.
[1] https://www.youtube.com/watch?v=fB-vEp3wr-0
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