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What If You Could See WiFi?

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Re: What If You Could See WiFi?

#31

Post by toyg »

afreak wrote: post #29
toyg wrote: post #23

Earlier quoted context omitted.

Well, radio pollution is still under debate. In Italy they've supposedly found significant discrepancies in cancer distribution near large radio transmitters (i.e. higher rates of cancer). We're talking humongous power and extreme proximity though, nothing like wifi.

Correlation is not causation. There has been no conclusive link between EM radiation and human ailments other than hysteria. We creatures have throughout history been bombarded with intense radio activity from outer space (such as the emissions from the crab nebula), and we are still alive and plentiful. Quit it with the fear mongering while ahead.

Upvoted despite the personal attack. Can we keep it civil ? I don't think I was fear mongering, I just said what was reported over there.

Re: What If You Could See WiFi?

#32

Post by Metrop0218 »

toyg wrote: post #31
afreak wrote: post #29

Earlier quoted context omitted.

Correlation is not causation. There has been no conclusive link between EM radiation and human ailments other than hysteria. We creatures have throughout history been bombarded with intense radio activity from outer space (such as the emissions from the crab nebula), and we are still alive and plentiful. Quit it with the fear mongering while ahead.

Upvoted despite the personal attack. Can we keep it civil ? I don't think I was fear mongering, I just said what was reported over there.

You most definitely were not.

Re: What If You Could See WiFi?

#33

Post by ANH »

Ignoring the images, the physical descriptions in this seem badly wrong. For instance, can any WiFi modulation scheme be described as, "The crests of waves is [sic] translated to a 1 by a computer, and the troughs equal a 0."?

Re: What If You Could See WiFi?

#34

Post by lambersley »

toyg wrote: post #23
noonespecial wrote: post #2

Illustrations like these do more harm than good. It lets people imagine that spaces are getting 'flooded' with 'stuff'. Radio is a light. A blinking light. A transmitting antenna like a light bulb. If your receiver can see the light blink (or a reflection of it) the signal gets through. Radio has the added benefit that (especially at longer wavelengths) most of the material world appears to be made of tissue paper.

Well, radio pollution is still under debate. In Italy they've supposedly found significant discrepancies in cancer distribution near large radio transmitters (i.e. higher rates of cancer). We're talking humongous power and extreme proximity though, nothing like wifi.

Causation or correlation?

Re: What If You Could See WiFi?

#35

Post by Ackley »

noonespecial wrote: post #2

Illustrations like these do more harm than good. It lets people imagine that spaces are getting 'flooded' with 'stuff'. Radio is a light. A blinking light. A transmitting antenna like a light bulb. If your receiver can see the light blink (or a reflection of it) the signal gets through. Radio has the added benefit that (especially at longer wavelengths) most of the material world appears to be made of tissue paper.

Where do you think interferences come from?

Re: What If You Could See WiFi?

#37

Post by lcedp »

sp332 wrote: post #12
lcedp wrote: post #4

Doesn't seem very legit to me. Firstly, if wi-fi would be visible, you still wouldn't be able to see it all like we can't see visible laser ray unless there is dust/water/something in the air. It should be reflected from something to be seen. But let's suppose it's just visible per se.. Ok, colors represent waves, but they don't look like 3-5 inches, more like meters on some photos. Secondly, signal strength should d…

"In two meters it should be four times as dark as in one meter" But our eyes compensate for inverse square laws, and have a logarithmic response to light.

Ok, point taken. It is vaguely a logarithm function. But what's the base of this logarithm? How much is it curved?

Just try light up a big room which has no windows with a candle - you can see pretty well at the distance of your hand, but in a few meters from you - it's plain darkness. I expect wi-fi waves to be like this.

Using the grath "Perceived Brightness" at [1] we have roughly the following table:

    Distance/Actual/Perceived Brightness
    1/100/100
    2/25/~55
    4/6.25/~30
[1] http://hyperphysics.phy-astr.gsu.edu/hbase/vision/bright.htm...

Re: What If You Could See WiFi?

#38

Post by sp332 »

lcedp wrote: post #37
sp332 wrote: post #12

Earlier quoted context omitted.

"In two meters it should be four times as dark as in one meter" But our eyes compensate for inverse square laws, and have a logarithmic response to light.

Ok, point taken. It is vaguely a logarithm function. But what's the base of this logarithm? How much is it curved? Just try light up a big room which has no windows with a candle - you can see pretty well at the distance of your hand, but in a few meters from you - it's plain darkness. I expect wi-fi waves to be like this. Using the grath "Perceived Brightness" at [1] we have roughly the following table: Distance/Act…

Luminous efficacy depends on wavelength, with the eye being most sensitive to 555nm (green) light at 683 lumens/Watt. Most wifi setups max out at 1W (I think?), so if the eye were as sensitive to wifi signals as to green light, we could get 683 lumens which is about the same as a 60W incandescent bulb.

Re: What If You Could See WiFi?

#39

Post by afreak »

toyg wrote: post #31
afreak wrote: post #29

Earlier quoted context omitted.

Correlation is not causation. There has been no conclusive link between EM radiation and human ailments other than hysteria. We creatures have throughout history been bombarded with intense radio activity from outer space (such as the emissions from the crab nebula), and we are still alive and plentiful. Quit it with the fear mongering while ahead.

Upvoted despite the personal attack. Can we keep it civil ? I don't think I was fear mongering, I just said what was reported over there.

It wasn't intended to be a personal attack and I do apologise for that, but I do get bothered when I see baseless accusations that non-ionising radiation is going to kill us all. Of course with enough intensity it could cause problems, but there are sources of high-powered EM radiation that bombard us every day that are from natural sources.

We won't be dying from this stuff any time soon.

Re: What If You Could See WiFi?

#40

Post by Ackley »

afreak wrote: post #39
toyg wrote: post #31

Earlier quoted context omitted.

Upvoted despite the personal attack. Can we keep it civil ? I don't think I was fear mongering, I just said what was reported over there.

It wasn't intended to be a personal attack and I do apologise for that, but I do get bothered when I see baseless accusations that non-ionising radiation is going to kill us all. Of course with enough intensity it could cause problems, but there are sources of high-powered EM radiation that bombard us every day that are from natural sources. We won't be dying from this stuff any time soon.

If radiations are strong enough that you can feel the heat, it means that your are cooking.
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