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Fantasma4500
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Electromagnetic radiation waves removal?
so - EMF, electromagnetic radiation comes from many sources, if one worries of this type of radiation typical solution would be to insulate EMF
emitting devices with material that can deflect these waves
now, do that with a whole room and youre just trapping them
of all my years the best bet ive heard at absolving these waves would be pieces of metal stuck in a pyramid epoxy-mold, thats kinda silly. i went
ahead and tested it, naturally, and they seem to make absolute no difference to an EMF source emitting 600 units - on the positive i did manage to
find a use for all the neat brass shavings and other colourful objects ive been collecting relentlessly- colorful chemical powders and even crystals
but- can i have some qualified guesses on how one can bring these waves to a stop? could something as simple as a metallic "bee-trap" work, like a
bottle with a small hole in the top where the waves get in, but arent intelligent enough to get back out of again and the waves just clashes with each
other until theyre neutralized? hm? legend has it you gotta fight fire with fire
some people have succeeded in using water however- whats the equal of water on fire with electromagnetic radiation waves? would we have to be looking
at specific wavelenght to construct a working device?
since were talking about waves, i remember as a kid, throwing a big rock into a wave neutralized it- it would make the wave either tip over and die
out or neutralize it before even forming, but this isnt quite water and the waves arent very visible
i believe this graph here explains how effectively various metals reflects electromagnetic radiation
https://www.researchgate.net/figure/Reflectance-of-films-of-...
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Twospoons
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Graphite loaded paint is the cheap option. Its conductive and dissipative. I've used it as a 'bandaid' fix for EMC compliance in a commercial
product, and the result was a rather astonishing 20dB reduction in emissions. (Thats a factor of 100 for those unfamiliar with dB)
EMC anechoic test chambers use carbon loaded conductive foam pyramids, backed with ferrite plates. They are big, and they are very, very expensive.
[Edited on 21-2-2022 by Twospoons]
Helicopter: "helico" -> spiral, "pter" -> with wings
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unionised
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Why?
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wg48temp9
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The OP should read the wiki on the subject see: https://en.wikipedia.org/wiki/Anechoic_chamber#Radio-frequen...
I am wg48 but not on my usual pc hence the temp handle.
Thank goodness for Fleming and the fungi.
Old codger' lives matters, wear a mask and help save them.
Be aware of demagoguery, keep your frontal lobes fully engaged.
I don't know who invented mRNA vaccines but they should get a fancy medal and I hope they made a shed load of money from it.
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MineMan
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Quote: Originally posted by Twospoons  | Graphite loaded paint is the cheap option. Its conductive and dissipative. I've used it as a 'bandaid' fix for EMC compliance in a commercial
product, and the result was a rather astonishing 20dB reduction in emissions. (Thats a factor of 100 for those unfamiliar with dB)
EMC anechoic test chambers use carbon loaded conductive foam pyramids, backed with ferrite plates. They are big, and they are very, very expensive.
[Edited on 21-2-2022 by Twospoons] |
Does this mean graphite loaded paint makes a crude RAM stealth coating? I heard carbon nano tubes is what the F-35 uses?
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Twospoons
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I imagine the F-35 stealth coating would be specifically tailored to radar frequencies - hence the nano tubes.
Generally speaking a conductive, but resistive, material (ie more conductive than air, but more resistive than typical metals) will absorb EM waves
and dissipate them as heat. How well it works will depend on a bunch of things - conductivity and thickness being two primary parameters. Graded
conductivity is probably also helpful to reduce reflections, by matching the impedance of free space to the impedance of the dissipative material -
this is one of the reasons for the cones in anechoic chambers.
Helicopter: "helico" -> spiral, "pter" -> with wings
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Herr Haber
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Correct. This is also why Russian SAM systems have several radar types per battery.
It's also how this happened:
https://www.c4isrnet.com/intel-geoint/sensors/2019/09/30/ste...
The news are slightly overhyped though. During the first gulf war decades old French approach radars could detect the F-117. Same thing for the same
reason with the F 35 and the German radar.
Furthermore, they could identify the F 35 because they knew they were there. Otherwise the radar operator could just have said "I believe something is
coming our way" which in reality is not much.
You just cant be stealthy against everything from any direction (and I'm not even mentioning distance!).
The spirit of adventure was upon me. Having nitric acid and copper, I had only to learn what the words 'act upon' meant. - Ira Remsen
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unionised
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| Quote: Originally posted by Herr Haber | Otherwise the radar operator could just have said "I believe something is coming our way" which in reality is not much.
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It's enough in a war zone.
If it's not ours, we shoot it.
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Fantasma4500
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wiki page- very interesting, so the third image from top has the text with it "Minimization of the reflection of sound waves by an anechoic chamber's
walls" - and this, minimization of reflection, would essentially equal destruction of the waves, or at least transformation into something else- and
if so, what? heat?
now, im finding this right here, but i dont quite understand if this really does concern dissipation of the EMF waves?
https://web.mit.edu/6.013_book/www/chapter11/11.5.html
@twospoons as for the graphite coating, it wouldnt matter if you covered up the graphite surface with another layer of paint- does it have to be a
surface coating?
as you mention ferrite on the back of these foam pyramids, magnets can work?
the waves gets compressed inbetween the pyramids, or do they get absorbed into the pyramids and then dissipated with magnetism?
interesting with these pyramid cones- so the woke folks were sort of right, but not really. i guess pyramid hat will become a thing eventually.
@unionised whether EMF is bad or not is controversial, but it may be related to drop in fertility and then theres a whole thing about tumors.
personally ive felt major mental disturbance in strong EMF fields. as with any potential danger its best to be one step ahead. there are guidelines
for safe exposure levels for a reason, supposedly.
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sauveurdumonde
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If by "worry about", you mean "this is going to hurt me", it's unlikely that they will unless you have a direct, high wattage RF beam directly pointed
at your brain. But even then, this would be from heating the tissue. RF is non-ionizing.
Now, if this was for, say, protecting sensitive electronics for a more accurate reading, this would make more sense.
Well, no, not really. Metals do reflect but they won't reflect forever. Especially if the shield is grounded. I think the photons create an electric
potential in the conductor. Someone please check my facts here if I'm wrong but I believe the photons (the EMF) is absorbed by the electrons in the
conductor, and the electron is brought to a higher energy level which in turn is converted to an additional electron. I know more about the physical
properties of photons than the quantum so I may be wrong. You should read up on the Photoelectric effect.
https://en.wikipedia.org/wiki/Photoelectric_effect
Not necessarily. In a completely closed box, no RF can escape. Even if the box had a hole in it, only the wavelengths smaller than that hole could
leave it. Since the distance between atoms, well, exists, very high energy photons may pass through as their wavelength is very short. But this is in
the x-ray/gamma range.
Wavelength in metres = 300/frequency in MHz
You may have a *psychological* phenomenon called Electromagnetic hypersensitivity, and I don't mean to say "it's all in your head" and call it a day,
because I know you aren't experiencing this on purpose- but I can almost assure you that if someone simply told you the room was filled with EMF, you
would feel it.
"There is a shadow of a nation behind you, the hope of a people... yet it may not matter. The Divide still stands against us."
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Twospoons
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| Quote: Originally posted by Antiswat |
@twospoons as for the graphite coating, it wouldnt matter if you covered up the graphite surface with another layer of paint- does it have to be a
surface coating?
as you mention ferrite on the back of these foam pyramids, magnets can work?
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The graphite doesn't need to be the top coating.
The EMC ferrites use compositions designed for EM absorption, known as soft ferrites. Ferrite magnets are not the same - they use compositions with a
high remanence, known as hard ferrites.
Two very different animals...
| Quote: Originally posted by Antiswat |
the waves gets compressed inbetween the pyramids, or do they get absorbed into the pyramids and then dissipated with magnetism?
interesting with these pyramid cones- so the woke folks were sort of right, but not really. i guess pyramid hat will become a thing eventually.
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The array of pyramids acts as an impedance transition between free space (377 ohms) and the resistance of the material they're made from, so at some
point the EM energy sees a matched load and gets absorbed. Look up transmission line theory if you want to get into the math and physics.
There's nothing magic about the pyramid shape - any array of long pointy shapes would work. Its just that a square base pyramid is easy to make and
convenient for tiling across a wall without leaving any gaps. Triangular or hexagonal prisms would work just as well. A wedge shape works too - it
doesn't have to be a regular pyramid.
The resin pyramids full of metal shavings are nothing but mystic nonsense designed to separate the gullible from their money. They achieve nothing,
apart from looking pretty.
| Quote: Originally posted by sauveurdumonde |
Not necessarily. In a completely closed box, no RF can escape. Even if the box had a hole in it, only the wavelengths smaller than that hole could
leave it.
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Yeah, uh, not strictly correct. A closed superconducting box would block all RF frequencies (right down to DC !) but with metals
theres always penetration into the metal. This is related to the skin effect - its a decaying exponential, which means there will always be a tiny bit
that gets through.
Same with holes - bigger waves can penetrate a hole, though they will be attenuated. The rule of thumb used in EE is no holes bigger than 1/20 of the
wavelength of the shortest wave you want to block.
[Edited on 22-2-2022 by Twospoons]
Helicopter: "helico" -> spiral, "pter" -> with wings
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Rainwater
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Dealing with intrinsically safe communication, I have to fight emf, static discharge, and what we term as auto-magnatisium.
( When an ungrounded, electrically isolated, conductor, becomes magnetized)
Think of emf as any other source of energy. As it moves through space and matter, it encounters resistance that will convert its energy into a
different form until it is completely disapated. Either my dilution or resistance.
Most of the equipment i install, is super sensitive hall effect sensors. Able to measure a magnetic field up to 16 meters from the detector and
determine the distance to 0.1mm. (Not as exciting as it sounds)
The easiest way to eliminate emf is to block it outright using a thick substrate.
0.5~1 meters of dirt will do a good job. 4 meters and 99% of radio transmissions are gone.
The next method is shielding. Simply encase your component in a conductive barrier. Google "Faraday Cage".
Next thought is what type of emf are you dealing with?
For example, Dirt will block higher frequency transmissions and will skeew and shift fm modulations but not pulse width transmissions or am
transmissions.
(It will block am but not as good as fm)
A 1mm thick aluminum faraday cage will block 50/60hz interfaces better than your favorite radio station.
I use shielded housing to protect my equipment and shielded cable to help protect my signals from interference.
1) If the shield is not grounded to an earth ground i can detect reflections(echo with phase shift) and amplified harmonics of emf sources in the
area, as well as my deired signal with the same refilections and harmonics.
I actually use the reflection magnitude to measure my cable length. Longer the cable, the greater the phase shift.
2) if both ends of the shield are grounded. This causes the shield to begin acting like an antenna with gain.
This increased distortion of the desired signal
As well as strengthen emf interference
3) by properly grounding 1 end of the shield, providing no ground ring, I can eliminate noise by 60-120db
The next thing to look at is the source of the emf.
Rf strength gets weaker with distance at a non linear rate.
Signal strength reduction at a given distance will be more than doubled at twice that distance.
Say you lose 1% of signal strength over a mile. You should expect more than 3% of signal loss at 2 miles. 7% at 3 miles.
So, if you can reduce the strength of the signal by a given amount at 1 meter from source. The reduction will have a greater effect over distance than
if the rf strength is reduced by the same amount at 10m from the source.
At your item, if the shield is 100mm away, it will provide more protection than if it is 10mm away
Next is natural capacitance. All materials have it. Anything with a physically defined structure. And some gases.
The more layers a given material has, The more capacitance it has.
Say you use a piece of aluminum foil to shield your item. Ok.
But you want the shield thicker. Because the thicker the conductor, the more energy it can channel away from your item, and the less emf it will be
exposed to.
So you put 3 layers on it. Thus, the total conductive of the shield has increased, so has its capacitance. Because of this, higher frequency will now
more easily pass through your shield instead of being absorbed by it.
I hope this was on topic.
[Edited on 23-2-2022 by Rainwater]
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mysteriusbhoice
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lol im gonna make a funny guess that this device can be repurposed to steal power from high voltage power lines by lining the ground with it and
hooking the wires up to some step down transformer then to some batteries/trailer.
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Fantasma4500
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| Quote: Originally posted by Antiswat |
personally ive felt major mental disturbance in strong EMF fields
[/rquote]
You may have a *psychological* phenomenon called Electromagnetic hypersensitivity, and I don't mean to say "it's all in your head" and call it a day,
because I know you aren't experiencing this on purpose- but I can almost assure you that if someone simply told you the room was filled with EMF, you
would feel it.
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i would say plausible if it wasnt because i was feeling it before i was even aware, it was quite something. i was practically unable to think and its
few times ive had anything coming remotely close to it, ive never been quite good friends with electronics.
anyhow so- the EMF trap, of course.. the waves have to get in there first, which requires a hole big enough for them to get in, and then they would
have to get stuck in some sort of geometry making it very unlikely that they could exit from again, supposing that they skip off - lets say, if they
impact a surface at 45 degrees- that they also leave that surface at the opposite 45 degrees, if you can say it like that in math terms
@twospoons speaking of "ferrites" not being magnets, i just whipped out my 3kg neodymium magnet which found me a few years ago
my PC is a quite stable source of EMF, just EMF meter laying on desktop it explains 60 units +-5
i was able to affect this number as much as quadrouble it if i placed the magnet inbetween the meter and the computer, it seemed to intensify the
signal the most when being just inbetween the two
as for the epoxy resin pyramids- many of them include some metal spring, usually copper, so for the lazy and impressionable person it would make
plenty enough sense to invest money into
@rainwater
yes faraday cage, its used in microwaves and aluminium is typically what they use, infact if you wrap a phone in 3 layers of aluminium foil youre
typically unable to call it, the older phone models seems to be easier to plug out like this
this also relates to what twospoons explained about hole size and blocking EMF waves
as for EMF - really anything generated by electronics, coming from electrical sockets (surprisingly this is downed a lot when you simply hit the
switch on an electrical socket that isnt being used), wifi and similar is probably the main concern- but also very much EMF generated inside any
normal house - im not quite sure what wavelenghts phones and wifi emit, i believe the wireless communications wavelenghts are getting smaller, 3G, 4G,
5G and eventually 6G
you mention grounding, in what sense grounding, like leading it back into electric socket as with the ground on most modern cables have?
"Rf strength gets weaker with distance at a non linear rate." a slight bit offtopic, theres a term for exponential, but there isnt yet one for the
inverse of exponential? last time i talked to someone about this we arrived at the conclusion that both decrease and increase is exponential
and, as for grounding- if one was to ground a 1x2m aluminium plate just in the middle of the room, that thing would essentially suck out all the EMF
waves that impacts it- and you could maybe even pump all that energy into something as a bonus?
now since you work with sensitive electronics, ive noticed that if i put bodyparts closer to an EMF generating device, then suddenly EMF meter will go
crazy if i put some entirely different bodypart near it, does it just magically absorb into your body or is this a glitch in how EMF meters work? i
did notice what you were explaining with EMF transmitting through cables, im kind of curious as for what levels an industrial welding machine puts out
as ive been welding some .. tank-heavy metal objects together, sometimes with the welding hose wrapped around me like a hungry snake. back in time one
specific welding machine- if workers did this it would end up killing them- something about it would syncronize their heartbeats- so when they would
stop welding they could faint and die as their hearts would stop
@mysteriousbhoice i mean, thats an honorable idea, but with all the 5G devices installed, and the fact that a 5G capable phone will actively- even
without sim (and battery?) seek the 5G signal- not knowing how strong this is compared to power lines, but probably quite strong- i think this would
be the easier way to charge your batteries, or tesla or whatever. or pockets.
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Deathunter88
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| Quote: Originally posted by Antiswat |
@unionised whether EMF is bad or not is controversial, but it may be related to drop in fertility and then theres a whole thing about tumors.
personally ive felt major mental disturbance in strong EMF fields. as with any potential danger its best to be one step ahead. there are guidelines
for safe exposure levels for a reason, supposedly. |
Um, no. Whether EMF harmful or not is only "controversial" in the pseudoscience community. What you need to do is see a psychiatrist, not ramble on
some internet forum about building a faraday cage.
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Twospoons
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To be fair to Antiswat, there are people sensitive EMF. Just far fewer than people who think they are sensitive to EMF.
I'm a little suspicious of this EMF meter you keep referring to. In the electronics game we would normally use a spectrum analyser to measure field
strengths, usually in units of µV/m ( or dBµV/m because logarithmic scales are more useful for these measurements). These devices are
eye-wateringly expensive, because they are complex and carefully calibrated (and because theres often a label on the front that says "Rhode and
Schwartz"  ).
So what exactly is this meter you are using? What frequency range does it cover? How does it do its measurements (thats critical to correct usage)?
And how has it been calibrated?
Grounding. *sigh* why is it there are so many people, especially EEs, that think there is this magical place where you can endlessly dump electrons
and they just disappear? "ground" is merely a reference point against which other measurements are made, and it can be anywhere you choose.
Everywhere else is "not ground", even if you connect it to "ground" with a big fat wire. Current always flows in loops, even though parts of the loop
may not be readily apparent.
Dont worry about 5G - its a short range system. The electric fields off your mains wiring will be far higher.
If you really want to charge batteries off free EM waves, use a solar panel. Theres far more energy floating about in the visible spectrum than in the
GHz region.
[Edited on 23-2-2022 by Twospoons]
Helicopter: "helico" -> spiral, "pter" -> with wings
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Texium
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Thread Moved
23-2-2022 at 13:31 |
Rainwater
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I'm not sure what an emf meter is, to be honest.
You got spectrum meters, wide band receivers, narrow band receivers, and oscilloscopes.
I'm assuming this thread is leaning toward the aluminum hat prospective, but im stuck in the electronic aspects of emf.
Electro magnetic forces
Most recivers use some form of amplification of signal, which can be affected by stationery magnetic fields. If you could provide details about your
meter (make, model, bandwidth, unit type) i could better explain what you're seeing and help you analyze the data collected.
If your observing an increase in "emf units" because you place a permanent magnet near your meter, that would suggest the meter is of the wide band
type using an opamp and trigger circuit to count emf pulses. The opamp circuit has a feed back resistor, which will be used to calibrate the circuit
gain, inductors and capacitor select the bandwidth of the receiver, and the position of the center point on the spectrum.
The wire of the circuit acts as an inductor with current passing through it. Current passing through an inductor is directly effected by magnetic
fields. Both moving and stationery. Google "Hall Effect"
The magnet may be holding the signal voltage closer to the trigger threshold which would increase the counter.
All in all this type of detector will not accurately tell you the strength of the emf exposed to it. As it is not measuring the strength of the emf
but the number of pulses counted per interval. These are very easy to make and are commonly known as "dummy sticks" or "contactless voltage detectors"
The sensations felt by emf are based on magnetic flux density. The conductive traces in your body are excited by induced current. For example, If
you're near a lighting strike (500m or less)
You will get about 0.5 seconds of sensation before the strike. (Hair standing on end and visual arcs)
The same can be felt near high voltage equipment (>400vac)
A similar feeling can be felt near high current devices such as welders. This is due to the capacitance of the body absorbing voltage induced into the
iron in your skin and blood. Same as when you get shocked by a door.
Cell phones, amateur radios, desktop computers do not produce strong enough emf to create a sensation.
| Quote: | | as for grounding- if one was to ground a 1x2m aluminium plate just in the middle of the room, that thing would essentially suck out all the EMF
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No. But if the plate was directly in-between your meter and emf source, blocking line of site, it would reduce the emf reading.
| Quote: Originally posted by Twospoons |
Grounding. *sigh* why is it there are so many people, especially EEs, that think there is this magical place where you can endlessly dump electrons
and they just disappear? "ground" is merely a reference point against which other measurements are made, and it can be anywhere you choose.
Everywhere else is "not ground", even if you connect it to "ground" with a big fat wire. Current always flows in loops, even though parts of the loop
may not be readily apparent.
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Electrical circuits - you are correct. Tho Earth ground is common ground point do to its uses as the "ground" starting at the power plant, all the way
to your outlet and every point in between. Unless an isolation transformer is being used.
Flux, not so much. Very very short reply, flux loops default to the strongest field present. In ambient area, that will be the earth. So earth ground
is very effective.
Long answer. We may need to start another thread.
(Edit) better explanation
https://en.m.wikipedia.org/wiki/Counterpoise_(ground_system)
[Edited on 24-2-2022 by Rainwater]
[Edited on 24-2-2022 by Rainwater]
"You can't do that" - challenge accepted
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Fantasma4500
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"DT-1130 High and low frequency radiation meter electromagnetic radiation meter" is the model im using as "EMF meter"
Level: low frequency: V / m, high-frequency: - μW / cm2
Measuring time intervals: 0.4 seconds
Frequency range: 50MHz-2000MHz
so- even with "grounding" theres no real way others than to simply let the EMF run out because it impacts so much air, particles or structure that it
loses its energy- and no real way to avoid it except for putting every electronic device into its own faraday cage- with pore holes 1/20 of its
emitted frequencies
i should maybe clarify, EMF as in Electro Magnetic Frequencies, probably quote close to EMForces?
i dont quite get how a material can at the same time be conducting and reflective of EMF- wouldnt this be contradictory- or is it because these waves
are to some extent conducted / absorbed and then later on decides to radiate/reflect back off?
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Twospoons
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| Quote: Originally posted by Antiswat |
i dont quite get how a material can at the same time be conducting and reflective of EMF- wouldnt this be contradictory- or is it because these waves
are to some extent conducted / absorbed and then later on decides to radiate/reflect back off?
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Ever see a reflection in a pane of clear glass? Same thing - some light goes through, some gets reflected. Or if you want to consider absorption,
look at gloss black paint - some light get reflected, some gets absorbed. This happens any time you have an abrupt change in the properties of the
medium a wave is travelling in.
Tried to look for info on your EMF meter : all I got was chinese sellers (this thing is about 6 bucks on Alibaba). Based on the price alone I would
be highly skeptical of any numbers you get out of this thing. Nobody builds accurate RF measuring devices for that kind of money.
By comparison, the last spectrum analyser I owned was a TEK492, built in 1980, that I got on EBAY for around $2k. The list price in 1980 was $60k -
about the same price as a house at that time. It had a span of 10kHz to 22GHz.
[Edited on 24-2-2022 by Twospoons]
[Edited on 24-2-2022 by Twospoons]
Helicopter: "helico" -> spiral, "pter" -> with wings
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Rainwater
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Found this. Its sold as a novelty item its just a wide band reciver hooked to a 8bit counter.
https://www.prc68.com/I/MeasuringEMFs.shtml#DT-1130
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unionised
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really?
"A systematic review of medical research in 2011 found no convincing scientific evidence for symptoms being caused by electromagnetic fields.[2] Since
then, several double-blind experiments have shown that people who report electromagnetic hypersensitivity are unable to detect the presence of
electromagnetic fields and are as likely to report ill health following a sham exposure as they are following exposure to genuine electromagnetic
fields, suggesting the cause in these cases to be the nocebo effect."
from
https://en.wikipedia.org/wiki/Electromagnetic_hypersensitivi...
Incidentally, the clever thing about inward facing pyramids is that they don't need to be "tuned" to the wavelength you are seeking to absorb.
The same idea is used in some laser beam stops.
A stack of raze blades bolted together makes a very good absorber.
[Edited on 24-2-22 by unionised]
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Twospoons
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I was just going from distant memory that the double blind tests found a few people to be sensitive, but that most who claimed to be sensitive
weren't.
I like the razor blade beam-stop idea - I have a 1.5W UV laser I will be firing up, once my safety glasses arrive, and I'm going to need a good
beam-stop.
@Rainwater : nice find. Your google-fu is clearly better than mine And from
those pics I would say my skepticism is well justified.
[Edited on 25-2-2022 by Twospoons]
Helicopter: "helico" -> spiral, "pter" -> with wings
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Fantasma4500
International Hazard
Posts: 1677
Registered: 12-12-2012
Location: Dysrope (aka europe)
Member Is Offline
Mood: dangerously practical
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i know its a broken topic to talk on a science forum about electromagnetic sensitivity or anything else that would set you apart from the flock
i found out last year that my bodytemperature is a stable 36.1*C, had this confirmed as we had bodytemperature checks by routine due to something
called corona
on my mothers side in my family we have always had some odd problems with electronics, when i was a child i remember walking into my parents bedroom,
all home alone the TV would turn on by itself. when i got older i learned that this wasnt actually supposed to happen, since then ive just had many
really bizarre happenings, i spent i believe the final count was 51 hours with help from 3 mechanics and 2 electricians installing radio in my car
it was as if every time we thought we had it figured out, something surreal just happened, like the wires switched around- the harness was butchered
from previous owners. oftenly when i walk by a radio it will drop out of signal and even when moving back away from it again. my uncle has had the
same thing with televisions and my mother has also had many lesser issues
im sure many life-long electricians have come across people who are simply cursed with electronics, and there are people who are really good with
electronics. i know one guy who almost got himself killed with chemistry so far 6 times, but in electronics hes a genius.
now, ahem, back to the topic if i may.
https://emfwatch.org/wp-content/uploads/2019/07/BBEG_2015_gu...
it could seem as if the DT1130 simply measures the middle one? which would for a very simple device also make most sense- kind of like when you buy
"salt" and they dont give you silver nitrate, which technically is also a salt
the machine also starts making more noise once you hit 100 units which coincides with the chart supplied.
looking around at youtube for reviews it turns out people who hunt for ghosts also use these devices- let me clarify thats not my intention, i feel
like i should maybe put that down aha.
i dont really mind the meter not being super sensitive as i dont really go for absolute null i just use it to get an approximate and maybe to see if i
can construct something that will take care of the more intense electromagnetic radiation. its all about balance
on a different similar meter i had, i tested the ... "active field" of a VR setup, virtual reality goggles- it uses 4 sort of cameras to track
movement of different devices you use to map you into an 3D environment, and even when it was off i believe readings were in the 600, where 100 is
considered harmful. and that was when that thing was off, never got to test it when the whole thing was running, plausibly it would hit 2000
as we dont have much research on how this new technology affects people, i would basically consider all of this exposure an experiment- and any
experiment requires a control group. and thats where i would like to "participate"
as for the foam pyramids, with carbon.. to act as conductive? the ferrite backplate must be doing something and since it at the end it sounds like it
definitely absolves the waves somehow
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Rainwater
National Hazard
Posts: 799
Registered: 22-12-2021
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Mood: indisposition to activity
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As for the stuff that happened when you were a kid. Id say you need a qualified electrician.
As for the radio problems in your car, check your negitave battery terminal, make sure its clean and bonded good. Make sure your grounding array is
secured properly. Tight and clean.
Make sure any after market electronics in your car have a dedicated ground wire that goes to the primary bond. Just bonding to the frame is not a good
ground.
Use farriet cores on your dc inputs. Verify the load doesnot exceed the alternator potential. And discontinue any prescription not properly
prescribed.
When installing electronics ensure your static has been discharged
"You can't do that" - challenge accepted
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Twospoons
International Hazard
Posts: 1282
Registered: 26-7-2004
Location: Middle Earth
Member Is Offline
Mood: A trace of hope...
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| Quote: Originally posted by Antiswat | \
on a different similar meter i had, i tested the ... "active field" of a VR setup, virtual reality goggles- it uses 4 sort of cameras to track
movement of different devices you use to map you into an 3D environment, and even when it was off i believe readings were in the 600, where 100 is
considered harmful. and that was when that thing was off, never got to test it when the whole thing was running, plausibly it would hit 2000
as we dont have much research on how this new technology affects people, i would basically consider all of this exposure an experiment- and any
experiment requires a control group. and thats where i would like to "participate"
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100 is considered harmful by who, exactly? And 100 what?
I think all you have proved is that this meter is not to be trusted.
All consumer devices must pass certain standards when it comes to emissions. FCC Class B in the US, CISPR 14 where I live or the European equivalent
(EN61000 ?) elsewhere. You should note that these standards have nothing to do with safety, and are all about non-interference with other devices.
Safety only kicks in at very high power levels - e.g. you wouldn't want to stand in front of a 20kW radar antenna.
Many studies of cellphone emissions have been done, and as far as I recall not one has found any effect other than slight heating. Given this is the
most powerful transmitter most people own, and it gets used against the side of your skull, you'd think any health effects would be pretty obvious by
now given just how many are in use.
Realistically there are far more dangerous things to worry about than EM waves e.g. driving a car.
Helicopter: "helico" -> spiral, "pter" -> with wings
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