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2450MHz radiation induces stress and anxiety like behavior in rats (2019)

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Re: 2450MHz radiation induces stress and anxiety like behavior in rats (2019)

#41

Post by sannee »

radioactivist wrote: post #39
strstr wrote: post #20

Earlier quoted context omitted.

Water has a strong absorption peak at 2450 MHz (it’s what kitchen microwaves use).

This is not really true. While the microwave absorption of water is significant at 2.4 GHz the peak is (a) quite broad and (b) centered at 10GHz or higher (higher if the temperature is raised); see plot in [0]. So ascribing some "specialness" to this frequency due to the abundance of water in living systems isn't an explanation. [0] https://en.wikipedia.org/wiki/Electromagnetic_absorption_by_...

To expand, apparently microwaving food right at the absorption peak sucks because of low penetrance, heating only the top layer of the food. The reason 2.4 GHz was chosen was purely as that is where the ISM band already was at the time.

Re: 2450MHz radiation induces stress and anxiety like behavior in rats (2019)

#43

Post by jazzyjackson »

strstr wrote: post #20
PragmaticPulp wrote: post #17

This is a 2019 study. Would be more interesting if anyone else had managed to replicate it. Reading the study doesn’t inspire a lot of confidence in their methods. They make a lot of basic errors like listing dB figures (a relative term) when I think they mean dBmw (an absolute measurement). They tested multiple frequencies but for some reason only 2450MHz showed significant effects. 900MHz and 1800MHz showed no effe…

Water has a strong absorption peak at 2450 MHz (it’s what kitchen microwaves use).

microwaves use it because water absorbs it + multiple wavelengths can fit inside the oven for even heating + easy to produce without fancy electronics

water can get shaken up by a wide band of frequencies

Re: 2450MHz radiation induces stress and anxiety like behavior in rats (2019)

#44

Post by gonzo »

PragmaticPulp wrote: post #17

This is a 2019 study. Would be more interesting if anyone else had managed to replicate it. Reading the study doesn’t inspire a lot of confidence in their methods. They make a lot of basic errors like listing dB figures (a relative term) when I think they mean dBmw (an absolute measurement). They tested multiple frequencies but for some reason only 2450MHz showed significant effects. 900MHz and 1800MHz showed no effe…

> when I think they mean dBmw (an absolute measurement).

I think you may mean dBm or dBmW here. 0dBm == 1mW.

The SI symbol for Watt is ‘W’ not ‘w’.

At 2.4GHz, free space path loss is -41dB at 1m, so even a 20dBm radio and a 20dBi directional antenna (and assuming 0dB of insertion loss), the signal strength at 1m is -1dBm, or about 0.79 mW.

At 3m, the free space path loss is nearly -50dB. Now the signal from the setup above is at -10dBm, or 0.1mW.

https://ecfsapi.fcc.gov/file/10417871820142/2018%2BRF%2BRadi...

Re: 2450MHz radiation induces stress and anxiety like behavior in rats (2019)

#45

Post by jazzyjackson »

sannee wrote: post #41
radioactivist wrote: post #39

Earlier quoted context omitted.

This is not really true. While the microwave absorption of water is significant at 2.4 GHz the peak is (a) quite broad and (b) centered at 10GHz or higher (higher if the temperature is raised); see plot in [0]. So ascribing some "specialness" to this frequency due to the abundance of water in living systems isn't an explanation. [0] https://en.wikipedia.org/wiki/Electromagnetic_absorption_by_...

To expand, apparently microwaving food right at the absorption peak sucks because of low penetrance, heating only the top layer of the food. The reason 2.4 GHz was chosen was purely as that is where the ISM band already was at the time.

i’m trying to google a better answer, it seems ISM bands were chosen when microwaves were a nascent technology, so it’s a bit chicken and egg

Re: 2450MHz radiation induces stress and anxiety like behavior in rats (2019)

#46

Post by TeMPOraL »

pajko wrote: post #26
drjasonharrison wrote: post #18

Earlier quoted context omitted.

And some say that it might be caused by very loud crickets. Because none of the electronics in the area died.

https://en.wikipedia.org/wiki/Directed-energy_weapon#Microwa...

https://en.wikipedia.org/wiki/Scattering

https://en.wikipedia.org/wiki/Diffuse_reflection

Re: 2450MHz radiation induces stress and anxiety like behavior in rats (2019)

#47

Post by R0b0t1 »

PragmaticPulp wrote: post #17

This is a 2019 study. Would be more interesting if anyone else had managed to replicate it. Reading the study doesn’t inspire a lot of confidence in their methods. They make a lot of basic errors like listing dB figures (a relative term) when I think they mean dBmw (an absolute measurement). They tested multiple frequencies but for some reason only 2450MHz showed significant effects. 900MHz and 1800MHz showed no effe…

1800MHz is not that close to 2450MHz. Behavior in air is different, for one, and the properties that dictate this, the vibrational modes of atoms and so on, are extremely selective.

Re: 2450MHz radiation induces stress and anxiety like behavior in rats (2019)

#48

Post by kumarvvr »

sandworm101 wrote: post #11
devwastaken wrote: post #9

Earlier quoted context omitted.

what exactly is a waveguide? How much stronger is that compared to something like a directional antenna at 1W rubbing your face?

It is a pipe that moves radio/light/sound waves from one place to another, usually between where they are created and where they are being used such as between transmitter and antenna or, in this case, between transmitter and rat in a cage. They look like normal pipes but inside have internal structure (ridges) designed to keep the waves propagating with minimal loss. In theory, a fiberoptic cable is a waveguide for…

> In theory, a fiberoptic cable is a waveguide for light

In practice too. Your statement makes it sound like its an exotic property.

Re: 2450MHz radiation induces stress and anxiety like behavior in rats (2019)

#49

Post by kumarvvr »

lifeplusplus wrote: post #5
dmitrygr wrote: post #3

100mW (19.8dBm, as per TFM) up close, delivered direct by a waveguide (as per TFM) is a whole lot of energy for something the size of a rat. Hardly a surprise that it would have an effect. Add more power and you can cook them.

I have 30 wifi around me, to which I'm exposed 24/7. There is something to be said about long term effects even if they aren't as high power

What is the power output range of those 30?

How far are you from them?

Is there anything between you and them?

Re: 2450MHz radiation induces stress and anxiety like behavior in rats (2019)

#50

Post by kumarvvr »

lifeplusplus wrote: post #30
Taniwha wrote: post #6

Earlier quoted context omitted.

but .... inverse square law ..... before you worry about wifi worry about the one known source of EMR that makes bigger fatter photons that do provably cause cancer .... you know the one, in the the sky, go out when it's visible and you can actually feel the photons

I also found out that brain cancer on right side has increased, likely due to cell phone use as most people are right handed. And that rats got brain cancer. And didn't california release health guidelines https://www.cdph.ca.gov/Programs/CCDPHP/DEODC/EHIB/CDPH%20Do... while radio freq wont cause ionizing radiation, it seems they are still capable of biological changes. I read they cause ions imbalance or something i…

All the potential health hazards, excluding brain cancer, may be related to high stress life that makes you use your phone a long time.

About the brain cancer thing, I highly doubt cell phone radiation could do anything significant as it is very low power.

Also, the study you linked only talks in vague terms like "may", "could", "still evolving", etc.

To me, it looks like a document put out to assuage some section of the electorate.

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