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Electrical Noise Causing Physiological Stress?
el johnno writes "The Globe and Mail is reporting on possible physiological problems caused by so-called 'dirty electricity.' Poor power quality caused by electrical feedback and harmonics from consumer electronics are cited as a possible cause of various 'physiological stress' problems. While previous research in this area looked for connections between EM fields and cancer, some research is now looking into possible connections to fatigue, headaches, depression, and other symptoms. From the article: 'If electricity were flowing in a constant way, most people's bodies would likely adapt, but with all the interference from modern devices, the resulting fields are too variable for people to get used to.'"
Quite likely.
If this was true anyone working in a UPS environment would be a sick nutter. Just take an oscilloscope and see the crap some "branded" dual conversion models spit out.
Baker's Law: Misery no longer loves company. Nowadays it insists on it
http://www.sigsegv.cx/
"Many people can't hear the sound at all without it being pointed out, but it is something that drives me crazy."
CRT tubes generally give off a frequency of about 17Khz (from memory
, someone correct me if I'm out which can usually be heard by people
under 30 but over 30 human hearing deteriorates to the point where
*most* people can no longer hear that high. You obviously are either
still fairly young or have good hearing. Or both! But one day you'll
probably find that you can't hear it either anymore.
Our RF exposure is only marginally greater when close to devices such as WiFi hotspots because of the immense amount of background EMI from TV and Radio broadcasts, satellites, CB and business radios, power transformers and a million other things.
Not least of which is the Sun; Earth's number one source of electromagnetic waves in every frequency. What's important here is that unlike solar radiation, which is largely random noise, man made EM radiation is generally ordered and harmonic. Overwhelmingly, most RF signals come from time harmonic sources.
Our brains and bodies are chaotic systems. Ordered signals are bad for them. Apparently epilepsy is a sudden bought of order in the brain. It's entirely possible that some people, or in deed all people to a degree, are sensitive to any resonances in their body with time harmonic signals.
Engineers sometimes scoff that EM radiation is at such a low level that it cannot harm anyone. But engineers very often make the mistake of not accounting for resonance
May the Maths Be with you!
Then the question is: what is the difference in a construction between a computer CRT and a television CRT that causes the former to be relatively silent? I always assumed that it is the deflector coils that are driven at the hsync frequency. Those coils are big and actually driven at that kind of frequency.
So to dissolve this dispute, I just did an experiment. With a good microphone, I recorded my TV set and then I looked at the waveform in Audacity. I counted 79+/-0.2 oscillations over 5051 microseconds, which gives an acoustic frequency of 15640 +/- 40 Hz for this PAL television. The PAL standard is 625 lines at 50 Hz, factor 2 interleaved, so the hsync frequency is 625*50/2 = 15625 Hz. This is within the margin of error equal to the observed acoustic frequency, which provides strong support for the hypothesis of the horizontal deflection coils causing the high-pitched tone.
For comparison, NTSC is 525 lines at 60/2 Hz, which gives 15750 Hz.
Note that I used an electret microphone which is not sensitive to the magnetic field emitted by the deflection coils.
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NTSC television uses a 15KHz horizontal frequency that audiably generates a 15KHz tone. The pitch is so high that most people really hear it like you would a baby crying, but they just sense it as being there. To me, televisions sound similar to ringing in the ears. High audio frequencies are very directional, and thats why you can always seek out the source.
Capacitors can also audibly resonate. When I was a kid, I used to build circuits with a little radioshack breadboard. One of the circuit projects consisted of making a cap buzz -- its very simple to do, especially on accident. Given the construction quality and engineering of cheap electronics these days, a buzzing cap wouldnt be too surprising.
I'm sorry, but you've just completely bought the snake oil. There are *no* controlled studies showing that low level EM has these kinds of effects, there are *no* studies showing a correlation between living near pylons and cancer or other diseases, there is simply *no* concrete evidence for any this. Experiements haven't disproved it? They haven't shown any reason to believe it's so. Experiments haven't disproved that we're all followed by clouds of invisible, undetectable green fairies, either. No matter how much you insist "It's so! It's so! It's obvious!" it is *not* obvious, and there is no reason for assuming it is so. Good luck on your NIMBY quest, which if carried to its obvious conclusion *will* cost lives--the services provided by electricty save lives every day.
Chris Mattern
"It is more than obvious now that we there is a serious problem with some people having a suceptability to certian frequencies and that those frequencies may not be the same for everyone affected."
So, since it's more than obvious (huh? What is "more" than obvious?) you should have no trouble providing the peer reviewed research.
The fact that you've assumed something is more than obvious, despite a dearth of supporting research, calls your motives into question.
"The fact that experiments may not show true correlation for specific frequencies does not disprove the problems."
Really? I thought that's exactly what they showed. Silly me.
How can we take you seriously when you dismiss the research you don't like and drawn a conclusion you do like (based on NO research) all in the same post.
"The government grants you rights, not the other way around."-- beav007. Yes, these people really exist...
- If it were true you'd expect stronger fields to make a bigger effect than miniscule ones.
- Therefore driving past a 500,000 watt radio or TV transmitting antenna should cause much much much greater symptoms than a 0.0000001 watt emissions from "dirty power". No such effect.
- People that are exposed to high EM fields, such as airport workers, tower light replacers, cell site testers, plasma physicists, industrial RF welders, TV technicians, walkie-talkie testers, they should all be really sick. Like 100,000 time ssicker than the average Joe or Jane Doe. They're not.
- At the neurological level, the voltage spikes from your nerves are 1,000's of times a bigger EM field than anything from outside your body. It's hard to imagine how a signal that's much weaker than your nerve impulses can have a noticeable effect.
- EM fields includes light, particularly sunlight. Sunlight hits you with almost 1,000 watts per square meter, many powers of ten greater than any other EM field, and most people think sunlight feels *good*, not bad.
Too many basic objections to this idea. Move on.The United States uses 120 volts, not 110 and has for some time. Old tube amplifiers have troubles due to the higher voltage.
Europe used to be 220 except the UK which was 240, now they are all moving to 230 (which is bad news for the UK - as higher voltage is more efficient, and being exactly twice the US is more convienient).
Frequency is kept regulated within very narrow bands, variations can disrupt the grid (parts of the grid need to be in phase and on frequency with each other to be joined - else huge currents flow - plus anything that was even trying to lag or lead from the rest of the grid would cause problems), also, clocks use the frequency for timekeeping, so even though a drop to 59 Hz in the US would still run most things just fine, over one day a clock would lose 24 minutes, hardly acceptable. Someone at MIT (I think) put a frequency changer before a classroom clock and was making class shorter and shorter each day to drive their prof batty.
100 volts in the US is way out of spec, 108-132 is the "acceptable" range, at 100 volts motors would be getting damaged or not run right, I'd be screaming at the power company if it was me getting that, computers would possibly have problems, would likely use more current to keep up the wattage, which could result in a positive feedback loop - if enough of the draw is such devices, less voltage = more current = less voltage until something gives way.
Just because it CAN be done, doesn't mean it should!