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Test Microwave for Radiation Leakage

ismymicrowaveleaking.isotropic.us

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Re: Test Microwave for Radiation Leakage

#51

Post by ganzuul »

KennyBlanken wrote: post #37
ganzuul wrote: post #23

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…

> 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…

No post body was provided.

Re: Test Microwave for Radiation Leakage

#52

Post by ganzuul »

dhdc wrote: post #31
ganzuul wrote: post #23

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…

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.

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.

Re: Test Microwave for Radiation Leakage

#53

Post by powerbroker »

jbothma wrote: post #28
dzhiurgis wrote: post #22

Earlier quoted context omitted.

So hard not to automatically press start. But one could also use fridge for this test.

I don't know, I'm not sure the fridge would give a good indication of the microwave's leakiness.

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.

Re: Test Microwave for Radiation Leakage

#55

Post by ganzuul »

gruez wrote: post #44
ganzuul wrote: post #29

Earlier quoted context omitted.

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.

>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

That article doesn't seem to talk about safety at all.

Re: Test Microwave for Radiation Leakage

#56

Post by dhdc »

ganzuul wrote: post #52
dhdc wrote: post #31

Earlier quoted context omitted.

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.

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 200…

How does a student living on their own has to do with anything about microwaves having "lethal potentials"? And what does the high-voltage capacitor has to do with sheet metals?

I'm sorry, but I really cannot follow your logic here.

Re: Test Microwave for Radiation Leakage

#57

Post by Retric »

dhdc wrote: post #48
Retric wrote: post #39

Earlier quoted context omitted.

> 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.

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.

The cage was originally there to make them more efficient, spraying microwaves into the room would mean you food takes a lot longer to cook.

Anyway, I don’t recall all the details but 1W from a microwave is probably an underestimate.

WiFi uses multiple separate frequencies and outside of what a microwave should be producing. So it’s significantly more energy to block it than you might think especially when the hub is closer to the device than the microwave.

PS: To be clear this is still a trivial amount of energy, just annoying when reheating food blocks WiFi.

Re: Test Microwave for Radiation Leakage

#58

Post by aimor »

An alternative method: build a LEctenna.

https://www.nrl.navy.mil/STEM/LEctenna-Challenge/

I stumbled across this little project a few weeks back, ordered the parts (just a diode and an led), and it works. Put a bowl of water in the microwave (or dinner), turn it on, then wave the lectenna around the cracks and see where it lights up.

I originally found the lectenna by researching if it was possible to power an LED wirelessly by leeching power from a house 60Hz line. I haven't made any progress on that, so if you have ideas I'd love to hear them.

Re: Test Microwave for Radiation Leakage

#59

Post by aimor »

Neat idea!

I went ahead I tried it with a 5GHz connection (the site was practically begging me to) and it turns out my microwave blocks both 2.4 and 5 GHz signals. Pretty cool! If your wondering, it's a decade old Sunbeam that I bought for $30 so nothing special.

https://ibb.co/JFcZp9H

Re: Test Microwave for Radiation Leakage

#60

Post by 1kurac »

jbothma wrote: post #28
dzhiurgis wrote: post #22

Earlier quoted context omitted.

So hard not to automatically press start. But one could also use fridge for this test.

I don't know, I'm not sure the fridge would give a good indication of the microwave's leakiness.

Neither does TCP over WiFi, really.
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