cab1
Posts: 9
Joined: Wed Mar 28, 2018 11:05 am
Location: DEU

Re: pi3: how to avoid "any" radiation?

Wed Mar 28, 2018 4:46 pm

which definitely has been proven in "Better Call Saul" ;-)

W. H. Heydt
Posts: 11104
Joined: Fri Mar 09, 2012 7:36 pm
Location: Vallejo, CA (US)

Re: pi3: how to avoid "any" radiation?

Wed Mar 28, 2018 6:36 pm

cab1 wrote:
Wed Mar 28, 2018 4:46 pm
which definitely has been proven in "Better Call Saul" ;-)
Would please quote the post you're referring to? By itself, it is difficult or impossible to determine which comment you are referring to.

W. H. Heydt
Posts: 11104
Joined: Fri Mar 09, 2012 7:36 pm
Location: Vallejo, CA (US)

Re: pi3: how to avoid "any" radiation?

Wed Mar 28, 2018 6:40 pm

cab1 wrote:
Wed Mar 28, 2018 4:20 pm
at a different frequency
While that is true, if you are not objecting to 50/60 cycle EM radiation, you have just "moved the goal posts". In terms of radiated power, this is the greatest amount of *artificial* radiation you're going to be exposed to, except for lighting.

Really...I suggest starting with a good course in Physics.

cab1
Posts: 9
Joined: Wed Mar 28, 2018 11:05 am
Location: DEU

Re: pi3: how to avoid "any" radiation?

Wed Mar 28, 2018 6:40 pm

W. H. Heydt wrote:
Wed Mar 28, 2018 6:36 pm
cab1 wrote:
Wed Mar 28, 2018 4:46 pm
which definitely has been proven in "Better Call Saul" ;-)
Would please quote the post you're referring to? By itself, it is difficult or impossible to determine which comment you are referring to.
In the film I mentioned there was a guy who did what you mentioned concerning aluminum foil...
(just a joke since it didnt help him)

User avatar
solar3000
Posts: 1051
Joined: Sat May 18, 2013 12:14 am

Re: pi3: how to avoid "any" radiation?

Wed Mar 28, 2018 7:30 pm

I emit infrared radiation.

One time I placed my phone in aluminum foil, then plastic sandwich bag. Then aluminum, then plastic. and all of that in a waterproof die cast aluminum case. then all of that under water in a cast iron bath tub.
It still transmits data. GPS was dead. So was bluetooth and wifi. but cellular was still connected.
go figure.

15 years ago, I placed my phone inside a sandwich bag and then under water. the signal was completely gone.
Antikythera

cab1
Posts: 9
Joined: Wed Mar 28, 2018 11:05 am
Location: DEU

Re: pi3: how to avoid "any" radiation?

Wed Mar 28, 2018 9:03 pm

W. H. Heydt wrote:
Wed Mar 28, 2018 6:40 pm
cab1 wrote:
Wed Mar 28, 2018 4:20 pm
at a different frequency
While that is true, if you are not objecting to 50/60 cycle EM radiation, you have just "moved the goal posts". In terms of radiated power, this is the greatest amount of *artificial* radiation you're going to be exposed to, except for lighting.

Really...I suggest starting with a good course in Physics.
Radiation energy (significantly) depends on the frequency. Thus, 50 Hz should have a "slightly different" physical effect than 50.000.000.000 Hz of a wifi client. Additionally, the "amount" of the effect on the human body strongly relates to the absorption capability of a certain frequency by biological cells. Whereas the first is quite understood, the second isnt. Nevertheless, I can not see any reason to absolve wifi radiaton from influencing my health just because living between a set of wires and sockets in my home didnt kill me up to now.

Sorry if my explanations dont meet your demands concerning physics ... really.

Heater
Posts: 13919
Joined: Tue Jul 17, 2012 3:02 pm

Re: pi3: how to avoid "any" radiation?

Wed Mar 28, 2018 9:37 pm

cab1,
Nevertheless, I can not see any reason to absolve wifi radiaton from influencing my health just because living between a set of wires and sockets in my home didnt kill me up to now
I suspect, you are far more likely to be killed by the 50Hz mains power supply to your home than any number of WiFi gadgets you are likely to have at home. At least there is evidence of mains power killing people whereas there is none for WiFi waves.

There are so many other more significant life threatening risks to think about.
Memory in C++ is a leaky abstraction .

W. H. Heydt
Posts: 11104
Joined: Fri Mar 09, 2012 7:36 pm
Location: Vallejo, CA (US)

Re: pi3: how to avoid "any" radiation?

Wed Mar 28, 2018 10:20 pm

cab1 wrote:
Wed Mar 28, 2018 9:03 pm
50.000.000.000 Hz of a wifi client.
One too many zeros.

Really....the bigger radiation danger is gamma emission from naturally occurring nucleides that are already *inside* your cells. Biggest risk is almost certainly the beta emission from K40 incorporated into biological molecules, and the recoil from beta emission of C14. The signals you're concerned about are completely trivial next to those issues...and you can't do *anything* about the K40 and C14.

Heater
Posts: 13919
Joined: Tue Jul 17, 2012 3:02 pm

Re: pi3: how to avoid "any" radiation?

Wed Mar 28, 2018 10:28 pm

Memory in C++ is a leaky abstraction .

hippy
Posts: 6281
Joined: Fri Sep 09, 2011 10:34 pm
Location: UK

Re: pi3: how to avoid "any" radiation?

Thu Mar 29, 2018 11:52 am

Whether the OP is 'talking out their backside', worrying over nothing, should be more worried about something else, isn't really relevant to the technical issue of eliminating or minimising whatever emission does come out of a Pi.

Discussions and refutation of a poster's personal beliefs would be best done elsewhere more suited to that.

jahboater
Posts: 4843
Joined: Wed Feb 04, 2015 6:38 pm

Re: pi3: how to avoid "any" radiation?

Thu Mar 29, 2018 12:55 pm

Make the whole house into a faraday cage :)

As for 50Hz em radiation, the wiring in the house is so short compared to the wavelength (which is nearly 6km) that I doubt it would radiate effectively.

User avatar
PeterO
Posts: 5152
Joined: Sun Jul 22, 2012 4:14 pm

Re: pi3: how to avoid "any" radiation?

Thu Mar 29, 2018 1:14 pm

jahboater wrote:
Thu Mar 29, 2018 12:55 pm
Make the whole house into a faraday cage :)

As for 50Hz em radiation, the wiring in the house is so short compared to the wavelength (which is nearly 6km) that I doubt it would radiate effectively.
λ = v/f
3E8 m/s / 50 Hz = 6E6 m (6000km)
PeterO
Discoverer of the PI2 XENON DEATH FLASH!
Interests: C,Python,PIC,Electronics,Ham Radio (G0DZB),1960s British Computers.
"The primary requirement (as we've always seen in your examples) is that the code is readable. " Dougie Lawson

jahboater
Posts: 4843
Joined: Wed Feb 04, 2015 6:38 pm

Re: pi3: how to avoid "any" radiation?

Thu Mar 29, 2018 1:25 pm

PeterO wrote:
Thu Mar 29, 2018 1:14 pm
jahboater wrote:
Thu Mar 29, 2018 12:55 pm
Make the whole house into a faraday cage :)

As for 50Hz em radiation, the wiring in the house is so short compared to the wavelength (which is nearly 6km) that I doubt it would radiate effectively.
λ = v/f
3E8 m/s / 50 Hz = 6E6 m (6000km)
PeterO
Ah yes!

With a 6000km wavelength, how much will a few metres of house wiring radiate ?

User avatar
karrika
Posts: 1072
Joined: Mon Oct 19, 2015 6:21 am
Location: Finland

Re: pi3: how to avoid "any" radiation?

Thu Mar 29, 2018 1:48 pm

If you are really into low radiation devices then have a look at small microcontrollers that can turn themselves off to a sleep mode.
I would also suggest looking into very low power chips. Arduino comes to mind...

The best design does not produce electric noise at all. But creating a noiseless design is art. Just putting chips on a board and using spread spectrum tricks to pass tests is far too common today.

droleary
Posts: 174
Joined: Fri Feb 09, 2018 3:45 am
Location: Minneapolis, MN USA
Contact: Website Skype

Re: pi3: how to avoid "any" radiation?

Thu Mar 29, 2018 3:10 pm

hippy wrote:
Thu Mar 29, 2018 11:52 am
Whether the OP is 'talking out their backside', worrying over nothing, should be more worried about something else, isn't really relevant to the technical issue of eliminating or minimising whatever emission does come out of a Pi.
If it's an actual technical issue, the OP should be interested in measuring the radiation that surrounds them rather that focusing on a single low-powered device like the RPi. Anything else is a premature optimization. Like I said, the odds are pretty good that radiation in the visible spectrum is the main "threat". Anything towards the UV side is going to be the most dangerous, and anything down into IR and microwave (outside of an oven) is going to be a minor issue. The impact of radio waves will likely be negligible.

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 24175
Joined: Sat Jul 30, 2011 7:41 pm

Re: pi3: how to avoid "any" radiation?

Thu Mar 29, 2018 4:13 pm

What Hippy said - please keep to the topic in hand.
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed. Here's an example...
“I think it’s wrong that only one company makes the game Monopoly.” – Steven Wright

ejolson
Posts: 3825
Joined: Tue Mar 18, 2014 11:47 am

Re: pi3: how to avoid "any" radiation?

Tue Apr 03, 2018 7:08 am

hippy wrote:
Thu Mar 29, 2018 11:52 am
relevant to the technical issue of eliminating or minimising whatever emission does come out of a Pi.
It would seem the rfkill command can be used to turn off WiFi and the Bluetooth devices. If the Pi is running headless, how do you turn off HDMI? Does reducing the clock speed reduce radiation? Is there anything else?

jahboater
Posts: 4843
Joined: Wed Feb 04, 2015 6:38 pm

Re: pi3: how to avoid "any" radiation?

Tue Apr 03, 2018 7:18 am

ejolson wrote:
Tue Apr 03, 2018 7:08 am
If the Pi is running headless, how do you turn off HDMI?
Do you mean:

$ tvservice --off
Powering off HDMI

mikerr
Posts: 2789
Joined: Thu Jan 12, 2012 12:46 pm
Location: UK
Contact: Website

Re: pi3: how to avoid "any" radiation?

Tue Apr 03, 2018 7:22 am

Turn off hdmi (until reboot)

Code: Select all

tvservice -o
Turn off BT and Wifi (permanently):

Code: Select all

sudo rfkill block all
Android app - Raspi Card Imager - download and image SD cards - No PC required !

Return to “General discussion”