29 ms·

I think this much radio waves around us constantly will end up being the lead pipes of our generation

EntrePrescott 4y ago
ya think the new version of the song will be: "Radio killed the Video Star" ? cf https://www.youtube.com/watch?v=W8r-tXRLazs https://www.youtube.com/watch?v=W8r-tXRLazs
josefx 4y ago
These radar sensors work because the signal is reflected from the surface of our bodies and doesn't penetrate. The most harmful things penetrate our body, even lead pipes wont hurt you until you drink the contaminated water.
- orbz 4y ago
  I’m pretty sure a lead pipe will hurt you if it penetrates your body. (Sorry couldn’t resist)
  - deleted 4y ago
    [deleted]
  - preisschild 4y ago
    A copper pipe would too :P
- lnsru 4y ago
  Your description fits perfectly for a perfect world. But there is no 100% reflection in a real world.
- anon223345 4y ago
  So it depends on the wavelength, but no, perfect reflection does not happen. Further, as an IOT engineer, I can tell you we do not currently have enough data to be sure I’m getting downvoted by people who probably aren’t even in the signals field lol… Remember just 70 years ago when “lobotomies were sound science and totally safe”
VLM 4y ago
What you're missing is range scales on square of power (or is it twice that for radar? I would think so) and all known forms of radiation have bio effects that scale by linear dose. So the 60 GHz presence detector transmits at +6 dBmW aka 4 milliwatts or 4 thousandths of a watt. As a side note microwave RF has never been known for power efficiency and I've built many a MMIC amplifier running under 1 percent efficient LOL. Something like a patriot missile AN/MPQ-53 radar transmits at 10 kilowatts, which is 2.5 million times the power of these detectors. If you want to burn thru radar jamming at 350 miles or whatever the unclassified spec is for the -53 radar, its going to take some serious wattage. Of course that's nothing compared to an old fashioned UHF broadcast transmitter or even a modern FM broadcast radio transmitter. Anyway the point of the above is in theory if RF caused cancer or death or covid or whatever its being blamed for now, the "medical signal" would be 2.5 million times stronger in military anti-aircraft units than in rando presence detector general public, to a first estimate. Seeing as there's no difference in death rates for ADA soldiers vs artillery or any other army branch that I'm aware of, and the rate would be 2.5 million times lower than... nothing... for general public using presence detectors, it seems unlikely that even massive scaling up to a billion users would have a measurable effect. Similar comedic examples can be generated for broadcast engineers. I'm friends with a couple broadcast EEs and old broadcast engineers just don't die (LOL). If a cellphone (100 times the power of a presence detector) gave even one human being per year early cancer, your average broadcast engineer would be dead in their first five minutes of work or something like that because they're always screwing around with enormous power levels, no matter if its permitted or not technically. The thing about electronics, is much like radiation, we can generate and measure sources over 9, maybe 12 orders of magnitude every day all over the planet.

ya think the new version of the song will be: "Radio killed the Video Star" ? cf https://www.youtube.com/watch?v=W8r-tXRLazs https://www.youtube.com/watch?v=W8r-tXRLazs

josefx 4y ago

These radar sensors work because the signal is reflected from the surface of our bodies and doesn't penetrate. The most harmful things penetrate our body, even lead pipes wont hurt you until you drink the contaminated water.

orbz 4y ago
I’m pretty sure a lead pipe will hurt you if it penetrates your body. (Sorry couldn’t resist)
- deleted 4y ago
  [deleted]
- preisschild 4y ago
  A copper pipe would too :P
lnsru 4y ago
Your description fits perfectly for a perfect world. But there is no 100% reflection in a real world.
anon223345 4y ago
So it depends on the wavelength, but no, perfect reflection does not happen. Further, as an IOT engineer, I can tell you we do not currently have enough data to be sure I’m getting downvoted by people who probably aren’t even in the signals field lol… Remember just 70 years ago when “lobotomies were sound science and totally safe”

VLM 4y ago

What you're missing is range scales on square of power (or is it twice that for radar? I would think so) and all known forms of radiation have bio effects that scale by linear dose. So the 60 GHz presence detector transmits at +6 dBmW aka 4 milliwatts or 4 thousandths of a watt. As a side note microwave RF has never been known for power efficiency and I've built many a MMIC amplifier running under 1 percent efficient LOL. Something like a patriot missile AN/MPQ-53 radar transmits at 10 kilowatts, which is 2.5 million times the power of these detectors. If you want to burn thru radar jamming at 350 miles or whatever the unclassified spec is for the -53 radar, its going to take some serious wattage. Of course that's nothing compared to an old fashioned UHF broadcast transmitter or even a modern FM broadcast radio transmitter. Anyway the point of the above is in theory if RF caused cancer or death or covid or whatever its being blamed for now, the "medical signal" would be 2.5 million times stronger in military anti-aircraft units than in rando presence detector general public, to a first estimate. Seeing as there's no difference in death rates for ADA soldiers vs artillery or any other army branch that I'm aware of, and the rate would be 2.5 million times lower than... nothing... for general public using presence detectors, it seems unlikely that even massive scaling up to a billion users would have a measurable effect. Similar comedic examples can be generated for broadcast engineers. I'm friends with a couple broadcast EEs and old broadcast engineers just don't die (LOL). If a cellphone (100 times the power of a presence detector) gave even one human being per year early cancer, your average broadcast engineer would be dead in their first five minutes of work or something like that because they're always screwing around with enormous power levels, no matter if its permitted or not technically. The thing about electronics, is much like radiation, we can generate and measure sources over 9, maybe 12 orders of magnitude every day all over the planet.