71–80 of 208 posts
I just find the German text message entertaining. The words and syntax are great. "Mir ist grad mein handy in den Landwahrkanal geplumpst" Geplumpst! Sounds exactly the right word for what just happened. "Jetzt könnte ich ein Bier gebrauchen" Couldn't we all.
Could someone translate?
My cell phone just fell into the Landwehr Canal
> Jetzt könnte ich ein Bier gebrauchen
I could use a beer now
(Google's translations, not mine)
I’m surprised to hear that bluetooth, GPS, and cellular don’t work in water. I wonder what’s the science behind this.
water absorbs 2.4GHz readily. this is why microwaves use that frequency to heat your food. microwaves are why that frequency band is unlicensed, too. so that's Bluetooth and wi-fi ruled out. GPS is a lower frequency, ~1.5GHz I think, and GPS is already an extremely low power signal. I don't know about 4g or 5g though.
Looks like Germany is 700-2600MHz for 4G, with 5G up at 3500MHz[0].
For underwater stuff it looks like you need something much lower in the kHz range[1], at least for distances of up to a couple hundred feet. Obviously this particular situation involves a much shorter distance. The page on MF radio[2] does mention water, and talks about frequencies up to 3MHz, but that's still way lower than any LTE bands used.
[0] https://www.gsmarena.com/network-bands.php3?sCountry=GERMANY
[1] https://en.wikipedia.org/wiki/Communication_with_submarines
I just find the German text message entertaining. The words and syntax are great. "Mir ist grad mein handy in den Landwahrkanal geplumpst" Geplumpst! Sounds exactly the right word for what just happened. "Jetzt könnte ich ein Bier gebrauchen" Couldn't we all.
Earlier quoted context omitted.
Radio is part of the EM spectrum. EM waves (including light) decay under water at an exponential rate due to absorption by the medium. So data transmission underwater must rely instead on mechanical waves (sound). This is why underwater robots mostly use tethers, otherwise you couldn't control them very well (RC control would stop working at a very shallow depth). Note: why are folks downvoting an honest question?
Don't EM waves decay at an exponential rate in all mediums?
> something happened that nobody of us would have imagined... this was the missing iPhone What a strange phrase, considering that was the goal.
I just find the German text message entertaining. The words and syntax are great. "Mir ist grad mein handy in den Landwahrkanal geplumpst" Geplumpst! Sounds exactly the right word for what just happened. "Jetzt könnte ich ein Bier gebrauchen" Couldn't we all.
Could someone translate?
Earlier quoted context omitted.
A phone or iPad will take 3T and work ok afterwards. I’ve seen engineers photograph the cold head on an MR scanner and the phone has held up just fine. Sometimes they turn off for a bit and need a little rest.
Unless they are taking the photo from near or in the bore, the camera isn't seeing anything like 3T (or, for that matter 1T). Most such photos are taken from outside the 5G line which is a very different kettle of fish. You are right that lots of electronics will be safe in the sense that it will not function in the field but be ok afterwards outside the room - so long as you don't move it around too fast. On the oth…
The iPhones I have seen go in have not had a lot of pull and can be held, even close to the bore (less than 1m).
The service instructions require photographs of various component - I watched a cold head get photographed recently.
I’ve also seen an engineer take a laptop pretty close. It turned off but didn’t suffer any lasting ill effects as far as we could tell.
All this fits in the category of ‘don’t do this’, but with care it is done by the engineering staff.
Earlier quoted context omitted.
Unless they are taking the photo from near or in the bore, the camera isn't seeing anything like 3T (or, for that matter 1T). Most such photos are taken from outside the 5G line which is a very different kettle of fish. You are right that lots of electronics will be safe in the sense that it will not function in the field but be ok afterwards outside the room - so long as you don't move it around too fast. On the oth…
The camera is taken right up to the bore. You’re right, it wouldn’t be 3T, but it’s getting close and it’s way inside the 5g line. The iPhones I have seen go in have not had a lot of pull and can be held, even close to the bore (less than 1m). The service instructions require photographs of various component - I watched a cold head get photographed recently. I’ve also seen an engineer take a laptop pretty close. It t…
Laptop is pretty crazy, what where they (not) thinking? I guess was imagining "normal" camera not phone, but you are right that modern attempts to make phones light have removed most of the magnetic material.
It doesn't take much to make it a problem (e.g. steel screws). Typical rooms are going to over 20g acceleration on ferromagnetic components in the highest gradient regions.
Earlier quoted context omitted.
> why people don't use magnets on strings to search for lost things in European canals more often. There are TikTok accounts devoted to this (where else?) - it seems surprisingly common to find safes.
... or they plant them :)