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Test Microwave for Radiation Leakage

ismymicrowaveleaking.isotropic.us

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Re: Test Microwave for Radiation Leakage

#71

Post by skeptikal »

AnotherGoodName wrote: post #62
fauria wrote: post #32

Earlier quoted context omitted.

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.

>Unplug the microwave. Pretty sure you need the earth though right?

I keep hearing that for Faraday cages but its not clear to me why.

Why should it be grounded?

The cell signal in the Faraday cage causes a mirror signal on the cages inner surface and the cage’s conductivity ensures that the potential is zero elsewhere in the cage.

Why do I need the ground? Is it a consequence of not having a perfect conductor?

Re: Test Microwave for Radiation Leakage

#74

Post by AnotherGoodName »

skeptikal wrote: post #71
AnotherGoodName wrote: post #62

Earlier quoted context omitted.

>Unplug the microwave. Pretty sure you need the earth though right?

I keep hearing that for Faraday cages but its not clear to me why. Why should it be grounded? The cell signal in the Faraday cage causes a mirror signal on the cages inner surface and the cage’s conductivity ensures that the potential is zero elsewhere in the cage. Why do I need the ground? Is it a consequence of not having a perfect conductor?

The case itself becomes an antenna if it's not and just re-resonates the signal.

Re: Test Microwave for Radiation Leakage

#75

Post by sandworm101 »

Or, just use an Ubertooth sniffer. From anywhere near a running microwave you should see it in the 2.4gh range. Its cool to see how some microwaves vary the frequency up and down during a cycle. It looks like a standing wave bouncing back and forth. This also explains the common office phenomena of the wifi dropping every time someone nukes something.

https://youtu.be/DCYrrNQc3lM https://youtu.be/6N3P842Nay8

Whether your phone can connect from inside is not a great standard. Your phone's antenna is maybe 1/100,000 the power of a microwave oven magnetron.

Re: Test Microwave for Radiation Leakage

#76

Post by dhdc »

aimor wrote: post #58

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 w…

Oscilloscopes often pick up some small voltage at 60Hz when the probe isn't connected to anything, and that voltage increases when a human touches the probe by acting as an antenna. But this is because of the scope's high input impedance(1-10MΩ); as soon as you try to power something off that, the voltage just collapse to zero.

Re: Test Microwave for Radiation Leakage

#77

Post by tomxor »

larsrc wrote: post #8

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.

Not only is there a massive difference in the power of a microwave oven compared to wifi, but the mechanism through which it heats food is dielectric heating [0] which does not occur in radio signals because they are not rotating fields.

This basic information is contained in the first very short paragraph of how a microwave oven works on wikipedia.

[0] https://en.wikipedia.org/wiki/Dielectric_heating

Re: Test Microwave for Radiation Leakage

#78

Post by dhdc »

sandworm101 wrote: post #75

Or, just use an Ubertooth sniffer. From anywhere near a running microwave you should see it in the 2.4gh range. Its cool to see how some microwaves vary the frequency up and down during a cycle. It looks like a standing wave bouncing back and forth. This also explains the common office phenomena of the wifi dropping every time someone nukes something. https://youtu.be/DCYrrNQc3lM https://youtu.be/6N3P842Nay8 Whether…

Ignoring impedance and assuming the microwave oven is rated at 1kW. 1kilowatt = 60dBm. A typical WiFi receivers works fine at -60dBm = 1 nanowatt. 60-(-60)=120dB, or 12 orders of magnitude. To put that into persepective, a WiFi receiver work with 1/1,000,000,000,000 the power of a 1kW microwave oven.

Re: Test Microwave for Radiation Leakage

#79

Post by dijonman2 »

noodlesUK wrote: post #17

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.

In dark mode it’s very legible. I expect most people know not to microwave their phones except maybe children.

Re: Test Microwave for Radiation Leakage

#80

Post by NikolaNovak »

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…

Am I wrong in ignorant understanding that if some radiation leaked, its' effect would largely be about heating affected body parts, which presumably you'd feel as, you know, heat; as opposed to some magical or teryfing "thing"?

In other words, why is microwave leaking worse than e. G. My oven leaking heat? Is potential small amount of microwave radiation In some specific way worse than feeling the heat when you open the oven after baking? I know radiation is a scary term but what is the real actual scientific documented risk here?

I know some pregnant families paid more money for microwave tests than their microwave costs and it never felt legit but I could be wrong.

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