[HN Gopher] Test Microwave for Radiation Leakage
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Test Microwave for Radiation Leakage
Author : uber1geek
Score : 40 points
Date : 2022-03-26 17:44 UTC (5 hours ago)
(HTM) web link (ismymicrowaveleaking.isotropic.us)
(TXT) w3m dump (ismymicrowaveleaking.isotropic.us)
| larsrc wrote:
| Isn't it lovely how we're inundating our homes with radiation at
| wavelengths that can cook meat? It's as if we _want_ the robot
| revolution to succeed.
| jodrellblank wrote:
| You mean like infra-red from the Sun when we have homes with
| windows?
|
| (A microwave is ~1 KiloWatt up close, WiFi is ~1Watt and meters
| away. This is like spreading fear that your house has a warm
| radiator which is bad because ovens use warmth to cook food).
| colanderman wrote:
| The only adverse effect microwaves have been found to have on
| humans is due to heating [1]. WiFi transmitters emit less than
| 1/1000 the power that a microwave oven does. Unless your cell
| phone starts to make you feel uncomfortably warm, I don't think
| you have to worry.
|
| [1] https://en.wikipedia.org/wiki/Microwave#Effects_on_health
| noodlesUK wrote:
| Idk if OP is the person who wrote this, but on my device the red
| text about not turning the microwave on is not especially
| legible. I'd probably make that text a bit bigger and/or
| brighter. I expect most HN readers will know not to microwave a
| phone but you'd be surprised what people might do.
| defanor wrote:
| Indeed, it's generally not considered legible on any common
| devices: WCAG suggests to ensure suitable perceived contrast
| ratios [1], and there are checkers around [2], while this
| page's #f00 on #36393F is far from meeting those.
|
| For the safety's sake, might be nice to also recommend to
| unplug the microwave oven altogether as the first step.
|
| [1] https://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-
| cont...
|
| [2] https://contrastchecker.com/
| hedora wrote:
| Alternatively, you could buy a microwave leak detector for
| $20-30.
| notorandit wrote:
| This thing is totally insane. Instructions are not clear at all
| and the risk that someone bakes a phone in a MWO or doesn't any
| other harmful thing is rather high. Please remove this post.
| dzhiurgis wrote:
| So hard not to automatically press start.
|
| But one could also use fridge for this test.
| mpreda wrote:
| In most cases, the fridge won't fit.
| jbothma wrote:
| I don't know, I'm not sure the fridge would give a good
| indication of the microwave's leakiness.
| powerbroker wrote:
| It might, if someone put their router in the microwave,
| simultaneously with the phone in the fridge... but at best
| it would prove that both the microwave and the fridge have
| leakiness.
| verve_rat wrote:
| I strongly disagree. If you are idiot enough to microwave your
| own phone, that's on you. This post is fine, and interesting.
| ganzuul wrote:
| You need a basic level of competence to be allowed in the
| kitchen. - That is where most domestic accidents happen.
|
| Funny how kitchen stuff was thought to be women's work once.
| gruez wrote:
| >Funny how kitchen stuff was thought to be women's work once.
|
| Clarification: _domestic_ kitchen stuff was thought to be
| women 's work, _professional_ kitchen stuff was thought to be
| men 's work (and still is[1]).
|
| [1] https://www.bbc.com/news/uk-wales-45486646
| ganzuul wrote:
| That article doesn't seem to talk about safety at all.
| fauria wrote:
| Agree that the warning: note: do not turn your
| microwave on for ANY portion of this test
|
| might not be visible or clear enough. I think OP should
| consider updating the instructions and set as a first step:
| 1. Unplug the microwave.
| tonymet wrote:
| with your phone outside , graph rssi and noise . turn on the
| microwave you will see it drop
| mateo1 wrote:
| My first thought was that it would try something like this. For
| a given sensitivity it's much easier to detect the 700W signal
| than the 2W one.
| xattt wrote:
| With the phone on the inside and the microwave on, the RSSI
| will drop quite rapidly as well.
| ganzuul wrote:
| I remain in awe that we trust the very cheapest plastic under
| repeat load and thermal cycling to form a -40dB seal, turning
| 700W into 70mW. Also, it seems that the outer metal shell of the
| device forms an active part of the circuit, so if it isn't
| plugged into a grounded outlet it sits at lethal potential. Then
| there is beryllium oxide in the thing...
|
| I kind of doubt an independent inventor could bring this to
| market with today's startup climate.
| KennyBlanken wrote:
| > I remain in awe that we trust the very cheapest plastic under
| repeat load and thermal cycling to form a -40dB seal, turning
| 700W into 70mW
|
| It's the metal grid in the window (with holes smaller than the
| wavelength of the microwaves), and the metal shell of the
| cavity, not any "plastic." The same reason the metal grid works
| is why there doesn't need to be a perfect door seal. As long as
| as the gap is smaller than the wavelength of the microwaves,
| it's fine.
|
| > Also, it seems that the outer metal shell of the device forms
| an active part of the circuit, so if it isn't plugged into a
| grounded outlet it sits at lethal potential.
|
| The shell doesn't sink RF, it reflects it. GFCI outlets
| (required in many areas for kitchen outlets) trip at 5mA
| differential between hot and neutral. No appliance is designed
| to sink current into ground unless there's an electrical fault.
|
| > Then there is beryllium oxide in the thing...
|
| Beryllium oxide hasn't been used in microwaves for a long time,
| and it presents zero risk unless the magnetron is smashed.
|
| Recommended reading for you:
|
| https://www.dannyguo.com/blog/my-seatbelt-rule-for-judgment/
|
| https://www.psychologytoday.com/us/basics/dunning-kruger-eff...
|
| Edit: They _can_ interfere with WiFi because a microwave could
| leak a _tenth of a percent_ of its nameplate power and it would
| overpower your access point by anywhere from 1x to 10x. Access
| points can, on certain bands, have radios up to ~1W, but
| 125-250mW is much more common.
|
| It would also be _completely harmless_ even if you were
| standing inches away from whatever the source of the leak was.
| Microwave RF energy only becomes dangerous when it is strong
| enough to heat up parts of your body that cannot cool
| themselves quickly due to having little /no bloodflow, like
| your eyes.
|
| You could put a parabolic antenna on your home wifi AP and
| standing in that beam would expose you to more RF energy than
| your microwave.
|
| I don't know why HN suddenly has a "DANGERS OF MICROWAVE
| OVENS!" boner this week...this is I think at least the second
| article on the subject of the 'dangers' of microwave ovens.
|
| Regarding "the door gap is a long line" - that would be
| relevant if the beam were aimed parallel (or close to parallel)
| with the gap...
| Retric wrote:
| > The same reason the metal grid works is why there doesn't
| need to be a perfect door seal. As long as as the gap is
| smaller than the wavelength of the microwaves, it's fine.
|
| The issue is the gap in a door normally forms a long line.
|
| The fact they interfere with WiFi should make it obvious the
| average microwaves faraday cage is far from perfect.
| dhdc wrote:
| The point of a microwave to have a faraday cage is not for
| preventing interference with wifi; the cage is there for
| preventing the microwave microwaving the user. At an
| average power of 1000W, even a thousand-fold attenuation
| (-30dB) means 1 watt/30dBm leaks out, minuscule for humans
| but enough to saturate typical wifi receivers.
| ganzuul wrote:
| Hello, Kenny.
|
| - Waveguides are manufactured to close tolerances for a
| reason.
|
| - The plastic in question is the hinges.
|
| - Lethal potential is a technical term, even though it is
| accepted that it is current that kills.
|
| - The people who recycle microwave ovens, that may have been
| in service for 30 years, want the copper and the ceramic
| dielectric is in their way. They smash.
|
| You are embarrassing yourself with your reading suggestions.
| jodrellblank wrote:
| > " _I kind of doubt an independent inventor could bring this
| to market with today 's startup climate._"
|
| Especially the kind of inventor who created microwaves for
| experiments with reanimating frozen hamsters, cough James
| Lovelock.
|
| (Tom Scott's video "I promise this story about microwaves is
| interesting" which includes a brief interview with James
| Lovelock last year at age 101 -
| https://www.youtube.com/watch?v=2tdiKTSdE9Y )
| dhdc wrote:
| A faraday cage does not require grounding to work, but its
| still recommanded to properly ground microwaves.
|
| Also, unless your electrician had a catastrophic fuck up, the
| metal cage will never be at live voltage, with or without
| grounding.
| ganzuul wrote:
| The specific scenario I have in mind is a student living on
| their own for the first time, cooking with a microwave in
| their room. Many catastrophic fuckups that we were quick to
| forget took place during this phase in life.
|
| You might take apart a microwave oven and discover that there
| are actually several pieces of sheet metal in them. Expensive
| ones connect them by staked wires. The capacitor is usually
| rated for 2000 volts and it packs quite a punch.
| aluminum96 wrote:
| What does this chart indicate?
| jodrellblank wrote:
| You load the web page on your phone, put it in to the microwave
| and close the door. The microwave should be a Faraday cage
| preventing microwave radiation getting through. Now the
| phone/web page cannot contact the internet. The chart stops
| updating.
|
| Unless there's a leak, then the chart continues updating while
| the phone is in the microwave.
|
| Then open the door and look if it could/couldn't keep pinging
| the server while the door was closed.
| FredPret wrote:
| I did this and now my phone has an extra 4gb of RAM
| dankle wrote:
| Mine has 5G now!
| bitcharmer wrote:
| This doesn't answer GP's question. How does it work? Why does
| my workstation connected to my router via ethernet cable show
| wildly varying results? What is the unit of Y axis?
| janci wrote:
| I think it tests latency of wifi connection. If wifi can not
| leak into the oven, microwaves can not leak out.
| dzhiurgis wrote:
| My bluetooth speaker always cuts out when nuker is on, but never
| notice any issues with wifi - wonder why.
| exac wrote:
| Because Bluetooth uses 2.4 GHz, and your wifi is on 5GHz.
| olx_designer wrote:
| Is this is an IQ test?
| bgro wrote:
| It says in red at the top to not turn on your microwave. This
| seems to be testing if WiFi waves can get through the
| microwave.
|
| It's interesting the browser can get access to this information
| with no prompts
| qorrect wrote:
| > It's interesting the browser can get access to this
| information with no prompts
|
| Exactly what information is it getting ? What Chrome API is
| this using ?
| [deleted]
| Karliss wrote:
| All it does is measures ping. No direct WiFi measurements
| just the timing of regular network requests.
| janci wrote:
| Yes. If you are able to follow instructions you will not turn
| the oven on with the phone inside.
| smegsicle wrote:
| unless it's a recent generation iphone w wireless rapid
| charging
| defanor wrote:
| > 1. Put phone on 2.4ghz wifi (5GHZ WILL NOT WORK!)
|
| Might be nice to expand on "will not work". Wouldn't 5 GHz Wi-Fi
| failing to connect show that it's even better at blocking, and
| would easily block 2.45 GHz too? And I'd think that they should
| block 5 GHz too, since those meshes look quite fine, and they
| probably try to be extra-safe.
| dhdc wrote:
| 5GHz actually has worse penetration and stronger attenuation
| over distance than 2.4GHz. Succesfully blocking 5GHz does not
| imply the same for 2.4GHz.
|
| However I do agree that it's probably still gonna work because
| the faraday cages on microwaves are always overkill (even the
| cheap ones).
| gruez wrote:
| > 5GHz actually has worse penetration and stronger
| attenuation over distance than 2.4GHz. Succesfully blocking
| 5GHz does not imply the same for 2.4GHz.
|
| In this case it could be the opposite: faraday cages only
| work for blocking wavelengths that are longer than the
| wavelength that it's designed for (presumably 2.4ghz).
| Therefore it could be blocking 2.4ghz but letting 5ghz waves
| through because it's too small to contain.
| dhdc wrote:
| As long as the hole size in the faraday cage is much
| smaller than the wavelength, it will work. The front mesh
| of a microwave typically has openings on the order of
| millimeters, which is still good enough for 5GHz.
| mountainboy wrote:
| a cheap consumer RF meter detects "high" levels of RF from 5+
| feet away, at least on the 4 or 5 random units I've tried. So
| the faraday cage doesn't seem to be doing its job in full.
| exmadscientist wrote:
| RF leaks can be pretty directional. So simple tests like
| this phone test or waving a power meter around aren't
| terribly sensitive. (But pay attention if you get a test
| failure!)
|
| There really isn't any substitute for a proper EMC chamber.
| dhdc wrote:
| A "high" from a random RF meter doesn't mean anything. Give
| me numbers in dBm/MHz.
| [deleted]
| nullrouten wrote:
| You would need to take your access point and wave it all around
| various directions in the space around the microwave. The "leak"
| could occur in a direction that doesn't have significant signal.
| Might be a better test to cook a large bowl of water, while
| testing your phone (outside the oven) on 2.4ghz ... holding it on
| all sides of the oven to see if any areas degrade the signal.
| This testing approach isn't that conclusive.
| gruez wrote:
| >This testing approach isn't that conclusive.
|
| Agreed. I just tested with two phones and one phone timed out
| but the other was able to maintain a connection. That would
| suggest that my microwave is maybe leaking. However I'm able to
| use the microwave without any noticeable effects from on 2.4ghz
| devices.
| dhdc wrote:
| A live test would be quite dangerous if the microwave does leak
| EM.
| dhdc wrote:
| Actually, this is not as stupid as it seems. I was first baffled
| by the idea that a website can read the RSSI of the device I'm
| on, then I realized its probably just measuring the latency by
| pinging every second.
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(page generated 2022-03-26 23:01 UTC)