high frequencies

[jonnobody]

Virtually every home in Europe, UK and USA is now saturated with high frequency radio waves for cellphones (800 to 2000 mHz) and wifi (2.4 gHz).  Are these harmful to humans and  can they be cancelled out by playing audible lower frequencies such as 40 Hz (good for alzheimers  - search . . .  szynalski/tone-generator/

[Strange]

24 minutes ago, jonnobody said:

Virtually every home in Europe, UK and USA is now saturated with high frequency radio waves for cellphones (800 to 2000 mHz) and wifi (2.4 gHz).

I don't know about "saturated". The levels of these signals are very low (cellphones are battery operated so can only transmit low powers.)

25 minutes ago, jonnobody said:

Are these harmful to humans

There is no evidence for that (and no plausible mechanism).

26 minutes ago, jonnobody said:

can they be cancelled out by playing audible lower frequencies such as 40 Hz

There is no way audio signals could affect radio waves (does your Wi-Fi stop working when you play loud music?).

And there is no way for a low frequency signal to "cancel out" a high frequency one. You would need the same frequency but in anti-phase (as in noise-cancelling headphones).

So: no.

Note that houses are also "saturated" with EM radiation at 50/60 Hz from the electricity supply.

28 minutes ago, jonnobody said:

40 Hz (good for alzheimers

I doubt it.

[studiot]

2 minutes ago, Strange said:

1) I don't know about "saturated". The levels of these signals are very low (cellphones are battery operated so can only transmit low powers.)

2) There is no evidence for that (and no plausible mechanism).

3) There is no way audio signals could affect radio waves (does your Wi-Fi stop working when you play loud music?).

4) And there is no way for a low frequency signal to "cancel out" a high frequency one. You would need the same frequency but in anti-phase (as in noise-cancelling headphones).

So: no.

5) Note that houses are also "saturated" with EM radiation at 50/60 Hz from the electricity supply.

6) I doubt it.

1) Agreed

2) https://ehtrust.org/france-new-national-law-bans-wifi-nursery-school/

3) Agreed

4) agreed

5) Agreed

6) No idea, but 40 Hz is getting close to the audio danger frequency (of 25 hz, if my memory serves me correctly) so it may have some effect but would it be good?

[Strange]

1 hour ago, studiot said:

2) https://ehtrust.org/france-new-national-law-bans-wifi-nursery-school/

That is evidence (some) people are concerned about it. I haven't (yet) seen any convincing evidence it is really a problem.

[Sensei]

12 hours ago, jonnobody said:

Virtually every home in Europe, UK and USA is now saturated with high frequency radio waves for cellphones (800 to 2000 mHz MHz) and wifi (2.4 gHz GHz). 

Entire world in day at noon is saturated  ("flood") by tremendous high frequency photons with 428 THz ... 749 THz..

ps. Saturation means that nothing can be put in anymore.. If world would be saturated by photons, everything would melt, and then turn state of the matter, and then change to plasma..

 

Edited June 26, 2018 by Sensei

[swansont]

Thermal radiation is omnipresent as well. Everything that has a temperature radiates; mostly in the IR, but some small amount is down in the microwave or even RF range. Every square meter of an object at room temperature (20 ºC) radiates ~ 400W of EM radiation.

[jonnobody]

Most 'evidence' of beneficial effects of sound are anecdotal (Mitchell Gaynor 'The Healing Power of Sound') but I found two trials. Whether they would be described as clinical trials or not is disputed - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4325896/

https://www.ctvnews.ca/health/the-sound-of-healing-study-says-sound-stimulation-could-help-alzheimer-s-patients-1.2868393

[koti]

It is also worth mentioning that the inverse square law applies to all sources of EM radiation so if you have a WiFi router which emits x amount of radiation at 1m, if you increase the distance to 2m you get x/2. If you increase the distance to 2m you get x/4, 4m - x/16, etc. Considering the low powers used in all GSM and WiFi appliences the potencial side effects which are disputable anyway, will be completely negligible. It is funny that just 2 days ago someone put posters all over my neighbourhood boycotting GSM antenas put on on nearby buildings when in fact that person receives orders of magnitude more radiation from his/her home appliances - which isn’t harmful in any meaningful way anyway. 

Edited June 28, 2018 by koti

[studiot]

1 hour ago, koti said:

It is also worth mentioning that the inverse square law applies to all sources of EM radiation so if you have a WiFi router which emits x amount of radiation at 1m, if you increase the distance to 2m you get x/2. If you increase the distance to 2m you get x/4, 4m - x/16, etc. Considering the low powers used in all GSM and WiFi appliences the potencial side effects which are disputable anyway, will be completely negligible. It is funny that just 2 days ago someone put posters all over my neighbourhood boycotting GSM antenas put on on nearby buildings when in fact that person receives orders of magnitude more radiation from his/her home appliances - which isn’t harmful in any meaningful way anyway. 

It is also worth considering the difference between 50 milliwatts of swansont's IR radiation and 50 milliwatts of digital signal, bearing in mind two things.

Quantum transitions depend on  frequency.

The IR signal is spread out over the cycle in the normal sine wave fashion. So the peak power is 1.1 times the rms or 55mW.

The digital signal can operate at a 10: 1 mark to space ratio so all the power is concentrated in short pulses, and the peak power is 10* 50 = 500 mW

 

Edited June 28, 2018 by studiot

[koti]

5 minutes ago, studiot said:

It is also worth considering the difference between 50 milliwatts of swansont's IR radiation and 50 milliwatts of digital signal, bearing in mind two things.

Quantum transitions depend on  frequency.

The IR signal is spread out over the cycle in the normal sine wave fashion. So the peak power is 1.1 times the rms or 55mW.

The digital signal can operate at a 10: 1 mark to space ratio so all the power is concentrated in short pulses, and the peak power is 10* 50 = 500 mW

 

How much would a 1,5kW vaccum cleaner emit ?