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deadly magnetic fields

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Marko

Fri Oct 05 2007, 11:30AM

Registered Member #89 Joined: Thu Feb 09 2006, 02:40PM
Location: Zadar, Croatia
Posts: 3145

Hi guys, I'm summoning all pseudoscience debunkers to gather.

Now for a while one of my professors has been pondering me about electromagnetic radiation from household items like computer monitors and cell phones causes cancer and other adverse health effects.
Oh, and overhead power lines too.
If you think that is odd, I can tell you that like 95% population over here is assured so.

He continued to poke me with his EMF/EMC/Electrosmog detector (I never figured out what the last letter really means). I just had to bring it home when he asked me to.

Now to admit, the device is really cool thing. Bringing it near computer monitor, unshielded line transformers, SMPS's, or cables which conducted noise and it lights the led's and buzzes.

It in general seemed to react to alternating magnetic fields, and I'll continue to call them so since there's no true 'radiation' in hertz range unless in hundreds of km from source.

The bad realizations happen when you actually start reading the manual and inscriptions on the device.

The device has a scale 2-30 labeled in ''MG'' (capital M). What in the world does this mean.. I don't think there are much devices around me producing magnetic fields in megagauss range.

2 is 'normal zone', 5 'accept zone' and up to 30 'prohibited zone' with 'adverse health effects'.

The manual shows that it was actually miligauss. Considering that earth's magnetic field is 300-600mG that's 'a tad too small'. Wawing it around seemed to have no effect but waving a
supermagnet in front of it at rate of just few Hz seemed to give full reading.
I got reading of 2 by quickly pulling it in and out of a steel barrel.

I opened it up.

There is a large air cored coil inside, unknown inductance, wound with 0.15..0.2mm wire, one output grounded, one goes into 4560D opamp:

Other IC's on board are LM324N and 12C508A microcontroller.

So, it definitely needs alternating magnetic field to work.
There is also some kind of spiral etched into board which leads nowhere. Haven't figured it's use yet, but could be some kind of pickup for electric field.

Apart from that, it doesn't look like it's a gauss meter at all since it appears to react to rate of change of field which is what gauss-meter inherently *shouldn't*.

It gives a heavy reading to cable inside the wall which conducts current from a light dimmer, seemingly due to massive HF harmonics produced by the dimmer.

Sinewave current of same peak value seems to give no reading at all.

So all it appears to do is measure the voltage induced on the coil and display it with LED bar.
Too high voltage = 'dangerous for health'.

Now some more pics, make sure to read the back of the package. Microwave ovens, cell phones, monitors and overhead lines, that's all the same dangerous radiation, and nobody cares that bandwith of the device is 30-300Hz...

I't s just defeating how 'professional' can pseudoscience get to make people buy something, how does one fight this?
Lot more to come into the topic.

Cheers,
Marko

Ken M.

Fri Oct 05 2007, 12:47PM

Registered Member #618 Joined: Sat Mar 31 2007, 04:15AM
Location: Us-Great Lakes
Posts: 628

Hi Marko,

I'd say if you really wanna have fun with your proffesor see what one of your tesla coils uts out as far as "Dangerous" EMF feilds (presumes it'll max out the meter), then inform your instructor of your findings including the test of a TC, and possibly get a good laugh.

ragnar

Fri Oct 05 2007, 01:02PM

Registered Member #63 Joined: Thu Feb 09 2006, 06:18AM
Location:
Posts: 1425

There have been connections found between cancer density and people living under large microwave transceivers (mobile phone cells) and TV transmitters, in Australia.

Although it may be pure chance, and whilst I'm convinced that EM fields in themselves wouldn't cause adverse effects, I've always pondered that minute tissue heating, possibly as a result of EM interaction, may be causing some of these statistical "symptoms"...

I'll quite plainly ignore someone who tries to convince me that transmitting towers and any kind of EM radiation "causes cancer" (typical words)... but it's quite a shame to see people (CHINA) deliberately capitalizing on misinformation and paranoia.

The sad thing is, you might imagine someone who designs/constructs/markets such a device, would be smart enough to be fully aware that no consequences exist of such interference.

BUT, A) the person/people who designed the contraption isn't/aren't necessarily the person/people who market it (MADE IN CHINA). [just looking at the picture, 'MISCARRIAGE, LEUKEMIA, STROKE'... how could you NOT buy that?

AND, B) you get perfectly smart people from time to time who have astounding "blonde moments" and pseudosciencey whims.

I'm not sure what'll come of this... I hope your professor does not hold your common sense against you. Try not to piss him off

hehe

Marko

Fri Oct 05 2007, 01:41PM

Registered Member #89 Joined: Thu Feb 09 2006, 02:40PM
Location: Zadar, Croatia
Posts: 3145

Matt: I'm no physician and let's say I have no clue what magnetic fields of any kind do to human body. But even still this is a grave example of pseudoscience. The scale device is 'callibrated' into is completely nonsensical, and it actually isn't a 'gauss meter' at all, but rather dB/dt meter of sorts.

Claiming that device does something it doesn't is inherently pseudoscientific at that very point.

Now, I would like to discuss that other part much more.
There are some more, to say, 'interesting' articles prof. pointed out.. but I'm afraid I'l need to get those from him.

I don't see for example how can 50/60Hz fields with enormous wavelengths interact significantly with something size of a human at all.
Yet to general public this is all the 'same' as with microwave ovens, cell phones and ''radiation'' from monitors and TV's (which isn't truly radiation but just leaking magnetic field from deflection coils.

Marko

uzzors2k

Fri Oct 05 2007, 03:03PM

Registered Member #95 Joined: Thu Feb 09 2006, 04:57PM
Location: Norway
Posts: 1308

A professor should know better. The requirements for high school teachers are exceedingly slack, at least here in Norway. Even if your marks are too poor for any form of higher education, you can still become a teacher. It should only take a high school level of physics to understand that electromagnetic radiation from consumer electronics (not counting microwave ovens) doesn't have the energy required to pose a health risk. Even if it does turn out to that long term exposure is unhealthy the effects are so slight nobody should bother worrying about it. There are more dangerous things out there like background radiation and pollution.

Is your professor the same guy who didn't believe James Randi?

(See Marko's signature)

sehrgut

Fri Oct 05 2007, 03:03PM

Registered Member #1017 Joined: Fri Sept 21 2007, 09:08PM
Location:
Posts: 24

Oh, those gadgets are fun! (But toal bunk, of course.) Didn't Information Unlimited used to sell something like that? I know there was a "magnetic field disturbance detector" in the old Laser, Phaser, Ion Ray Gun book. . .

Marko

Fri Oct 05 2007, 06:07PM

Registered Member #89 Joined: Thu Feb 09 2006, 02:40PM
Location: Zadar, Croatia
Posts: 3145

Hi guys

The thing also definitely reacts at alternating electric field (that's what this copper snail under the coil is for).
Holding the one side of the device in hand, and other side on a TV screen makes it beep to maximum; embracing fully effectively cages it, reducing the displacement current and readout to zero.

This is just how misleading the thing is.

It should only take a high school level of physics to understand that electromagnetic radiation from consumer electronics (not counting microwave ovens) doesn't have the energy required to pose a health risk.

Now can you prove this? There are thousands of articles and statistical research over internet,
and 'statistics' are usually in writers favour.

Half of the world uses cell phones and cancer is on of major causes of death. So do the cell phones cause cancer? Correlation does not imply causation so answer is *you don't know*,
and you can't say it doesn't just from lack of observational evidence, you need *evidence* which proves it doesn't - that's how I get poked most of time.

I would be pleased if someone could help me on that matter.

Is your professor the same guy who didn't believe James Randi?

No, luckily he isn't... That's a quote from wikipedia.

Hazmatt_(The Underdog)

Fri Oct 05 2007, 06:16PM

Registered Member #135 Joined: Sat Feb 11 2006, 12:06AM
Location: Anywhere is fine
Posts: 1735

2 or 10 mgauss
5 or 20 mgauss well shoot ... which is it huh?

It's a piece of junk. It's basically an AM radio and a sensitive pickup coil. If you get it near a flyback or TC the input stage might get damaged because of electrostatic charging.

30Hz to 300Hz range, you know... that's pretty much useless.

What I would do is show him a giger counter! Show him how much radiation is coming out of you and out of him. Then put it next to a concrete wall and tell him he's getting BAKED! Then tell him how much radiation he gets from standing next to you and that the sun is just spewing out ENORMOUS amounts of alpha, Beta, Gamma and X-ray radiation every second!

Then get back to me about how long it took him to turn white and have all his hair fall out, okay ^^.

HAHAHHAHAHAHHAHAHAH

ShawnLG

Fri Oct 05 2007, 06:58PM

Registered Member #286 Joined: Mon Mar 06 2006, 04:52AM
Location:
Posts: 399

My 21" monitor puts out a lot EM radiation. Enough to light an LED, should I be worried?

Dr. Slack

Fri Oct 05 2007, 07:23PM

Registered Member #72 Joined: Thu Feb 09 2006, 08:29AM
Location: UK St. Albans
Posts: 1659

What really irritates me about this sort of thing is that I'm quite clever with electronic stuff, quite bright enough to design something like that, but nowhere near smart enough to package it and sell it to the gullible for a profit. Damn, I'll just have to keep working for a living!

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