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How do MRI Headphones work? (2022)

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Re: How do MRI Headphones work? (2022)

#161

Post by r2_pilot »

Traubenfuchs wrote: post #137

Ok, interesting, makes sense. Next, explain to me why the MRI machine does not... take itself apart? In an MRI machine without a cover you can see all kinds of micro and macro machinery, cables, fans, plating, sensors, magnetrons, pulse transformators, gun drivers... Pretty much each of those parts would be pulled through the room and get stuck to the MRI machine if brought in individually, or am I wrong? https://www…

The engineers have accounted for this and appropriately fasten the individual components to the machine rather than bringing the parts in for assembling the machine while the high powered magnetic field is present.

Re: How do MRI Headphones work? (2022)

#162

Post by arethuza »

adolph wrote: post #157
mnw21cam wrote: post #45

Earlier quoted context omitted.

With socks, wear levelling is actually really useful. I tend to buy a whole rotation of identical black socks, and then I don't need to pair them up individually. Also, buying 15 pairs of socks in one go isn't going to break the bank.

Wear leveling socks is a critical challenge for me. Unlike larger clothes, socks don’t stack easily, so defy conventional methods of stock rotation. How do you approach this? Would it make sense to buy one of those shelf springs that grocery stores use to keep boxes towards the from of the shelf?

You need "Socks as a Service" (we could call it "SaaS") - every day someone drops off a new pair of socks and picks up your previous pair.

If you pay for a premium plan then no multi-tenanting and only you get to wear any particular pair of socks.

Re: How do MRI Headphones work? (2022)

#163

Post by turnsout »

bdowling wrote: post #120
porknubbins wrote: post #118

Earlier quoted context omitted.

Sounds ingenious but I don’t quite follow the story. Why would a stewardess make you stop? Was there some system where you had to pay for headphones separately to hear a movie? I’m pretty sure all I remember are headrests having standard 1/8” audio jacks.

Yes, they would charge for headphones to watch the movie. The movie (there was only one, or maybe two on a long international flight) was played on CRT monitors mounted on the ceiling of each cabin section. That was 20+ years ago, before flat panel screens in every headrest that could tune into one of a couple dozen looping channels, and long, long before you could watch anything at any time from a huge library.

Before that, they actually ran film projectors in some planes, using a variety of half-baked schemes.[0] Wild times!

[0]: https://en.wikipedia.org/wiki/In-flight_entertainment#Histor...

Re: How do MRI Headphones work? (2022)

#164

Post by jplona »

DennisP wrote: post #48
cuonic wrote: post #14

They also use a similar mechanism for the "get me out of here ASAP" panic button [0] that staff place in your hand and tell you to squeeze if required, all it does is detect a change in air pressure on the other end of the tubing. [0] https://www.mriequip.com/store/pc/MRI-Non-Magnetic-Magnalarm...

My house came with a button like that for the garbage disposal. Previous owner didn't like the idea of using an electrical switch with wet hands.

I believe this is required by code in some places, depending on the location of the switch. Mine is inset into the counter top, so plenty of opportunity for water to pool around it which I think would rule out an electrical switch.

Re: How do MRI Headphones work? (2022)

#165

Post by chriscjcj »

treve wrote: post #37
snakeyjake wrote: post #21

>The only headphone tech that I was aware of or that I'd ever really considered I guess I'm old now because this style of headphone was present on every model of passenger aircraft in the sky when I was a young adult.

I've never heard this before! When I started flying it was just the 2 mono jacks that you still see on planes that haven't been updated (always wondered why it wasn't just a stereo jack) Pretty surprising to hear there's air/sound tubes rigged on to every seat on a plane. Seems like the sound tubes ended in the 70's: https://apex.aero/articles/sound-tube-surprising-history-air...

In my "maybe I'll need it some day" pile, I still have the two-mono-plugs to one stereo jack adapter I bought at Radio Shack so I could stick it to The Man. I think I only used it half a dozen times.

Re: How do MRI Headphones work? (2022)

#166

Post by fluidcruft »

throwaway2037 wrote: post #122
fluidcruft wrote: post #79

One of my favorite ISMRM posters that I saw in Toronto years ago was titled something like "a low-cost MRI-compatible communication system". It was really well written and you had to look at the photos to fully realize it was actually two Dixie cups connected by a string.

Man, you really nerd sniped me here. First: ISMRM means "International Society for Magnetic Resonance in Medicine" from here: https://www.ismrm.org/ I found a bunch of posters here, but I could not find the exact one that you mentioned: https://www.ismrm.org/19/program_files/DP02.htm Maybe lost now? Or a different page?

I'm pretty sure it was the 2008 ISMRM meeting (small chance it may have been 2003). I don't think it was actually submitted, because I couldn't find it in the proceedings even back then. I think whoever it was smuggled the poster into the hall and hung it among the others as a prank. I'm pretty sure the dead salmon fMRI poster was also there at the time but I can't remember if that was in the proceedings. The dead salmon fMRI did end up being published though and making quite a stir.

Re: How do MRI Headphones work? (2022)

#167

Post by Tagbert »

PufPufPuf wrote: post #147
Aachen wrote: post #144

Earlier quoted context omitted.

A button for garbage disposal before you have a chance to dry your hands? What does this button do, activate some pneumatic tube system so you don't have to carry trash to the bin?

They're talking about the "trash blender" that's common to be installed in American sinks

“Trash compactor”

It is an in-cabinet trash can with a mechanism to compress the trash when you push the button. I don’t know how common they really are. I’ve only know a few people with them. I could see where they might be more popular in apartments where you can’t easily take your trash to an outside trash can. They do require special, heavy-duty trash bags to handle the pressure.

Re: How do MRI Headphones work? (2022)

#168

Post by cortesoft »

nessus42 wrote: post #72
snakeyjake wrote: post #21

>The only headphone tech that I was aware of or that I'd ever really considered I guess I'm old now because this style of headphone was present on every model of passenger aircraft in the sky when I was a young adult.

When I was a kid, I once brought a stethoscope with me on the airplane so that I could watch the movie for free. (Or rather listen to it.) I pulled off the heart-listening cup part of the stethoscope and inserted beverage straws into the rubber tubing. Then I put one straw into each of the two little holes in the armrest. It worked perfectly! Until a stewardess caught me and made me stop.

I used to just pull the armrest up next to my ear and listen directly out of the hole.

Re: How do MRI Headphones work? (2022)

#169

Post by DennisP »

Tagbert wrote: post #167
PufPufPuf wrote: post #147

Earlier quoted context omitted.

They're talking about the "trash blender" that's common to be installed in American sinks

“Trash compactor” It is an in-cabinet trash can with a mechanism to compress the trash when you push the button. I don’t know how common they really are. I’ve only know a few people with them. I could see where they might be more popular in apartments where you can’t easily take your trash to an outside trash can. They do require special, heavy-duty trash bags to handle the pressure.

What I'm talking about is an electric grinder that that sink drains into. Lots of people have them in the US.

Re: How do MRI Headphones work? (2022)

#170

Post by DennisP »

jplona wrote: post #164
DennisP wrote: post #48

Earlier quoted context omitted.

My house came with a button like that for the garbage disposal. Previous owner didn't like the idea of using an electrical switch with wet hands.

I believe this is required by code in some places, depending on the location of the switch. Mine is inset into the counter top, so plenty of opportunity for water to pool around it which I think would rule out an electrical switch.

Mine is also in the countertop, makes sense that code would require it in that case. Previous owner didn't like the idea of wet hands on a wall switch.
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