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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)

#11

Post by sandworm101 »

devwastaken wrote: post #9
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.

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 light.

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

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

#12

Post by stagger87 »

devwastaken wrote: post #9
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.

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

A waveguide as it pertains to RF is just an enclosed hollow metal pipe that can carry RF energy. The size of the tube determines the ideal frequency it can carry (without excessive losses). I believe at 2.4GHz, a common waveguide is roughly the diameter of a tennis ball cannister, so it's probably easy to put a directly a rat inside the waveguide (I can't read the article so I'm not sure if they do this). In theory though, there is no reason a directional antenna couldn't be used to deliver the same amount of power, the waveguide might simply be more convenient.

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

#13

Post by emeraldd »

devwastaken wrote: post #9
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.

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

Directional antennas come in different forms each with slightly different characteristics sonit's very hard to say. Your also talking about a lot less mass in a mouse than in a human head. With the wave guide at close enough range, you can assume a much higher percentage of the energy is hitting the mouse than say a yagi, but the specifics depend a lot on the design of the system.

To answer the other part of the question, you can think of a wave guide like a tuned pipe for rf to travel down. In alot of cases they are literally just empty tubes that are correctly tuned for the frequency fed into them.

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

#14

Post by WrtCdEvrydy »

throwaway803453 wrote: post #2

I have a small apartment and realized my WiFi router power levels are by default set to 100%. I dropped it to 25% with no meaningful reduction in bandwidth. It's a simple precaution and while I don't believe I am sensitive to RF fields maybe my neighbor's children are.

The issue that the ISP doesn't want complaints so those routers are always set to auto-hop at maximum speed.

Since most apartment complexes use the same company, the hops are always around the same time so you basically have these routers screaming at maximum speed and moving between channels.

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

#17

Post by PragmaticPulp »

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 effects, despite 1800MHz being relatively close to 2450MHz.

They also didn’t use very many rats for each group. Only n=6 per frequency, which were further divided into n=3 for some of their measurements because they couldn’t use the same rat for both tests. They also chose a lot of stress-related measures which are known to be heavily influenced by mishandling the rats (e.g. if a researcher accidentally dropped one during handling)

Unless someone can replicate these results and do it with more rats, I suspect the results are likely from one or maybe two rats having abnormal baseline results and that being amplified by the ultra-small sample size.

As for relevance: Unless you’re standing in close proximity to a high-gain, directional antenna emitting continuous wave tones (not intermittent modulated WiFi packets) then your WiFi exposure won’t come anywhere near what they used for these experiments. Inverse square law and omnidirectional antennas mean that very little WiFi energy even makes it to people near a WiFi router.

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

#20

Post by strstr »

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).
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