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Measuring Microwave Output From A Laptop?
bethorphil asks: "I was shopping online for a laptop today, and as I was choosing my processor speed, I noticed that the clock frequency of a decent CPU (2.4 GHz) was about the same frequency as the radiation used in a microwave oven. This got me thinking about recent headlines of laptop heat causing male infertility. If the heat alone is a threat, It would make sense that holding a 40-watt microwave emitter in your lap could cause even more serious problems down the road. I assume (optimistically, perhaps) that laptops are designed to shield the user from radiation, and not just to protect the system from interference. , but what I'd really like is a way to test for myself how much microwave radiation actually comes from my laptop. So far, the most interesting thing my searches have come up with is this quack-tastic low emission PC, but actual tools for an amateur to measure this stuff seem hard to come by. What's the best way to find out if my laptop is nuking the family jewels?"
As for how to measure the amount of microwave radiation a laptop emits, that would require special equipment that you are not likely to have at home. But the FCC does put serious limits on the RF that it's allowed to emit. I'll bet the actual microwave RF emitted is under a watt. Probably less than 1/10th of a watt.
Now, if you have WiFi, that will emit about 250 mW of power when it's actively transmitting. Which is a small percentage of the time. But your WiFi card probably does emit more microwave radiation than the rest of the laptop combined ...
As for microwaves causing infertility, that has yet to be really shown.
What's the best way to find out if my laptop is nuking the family jewels?
Breed. If your kids come out with extra limbs, scales-for-skin or superpowers, then it is.
No sig
Most modern high clock frequency CPU's have an internal phase-locked oscillator (in this case 2.4ghz) that's synced to a low-frequency external crystal. The Front Side Bus frequency is about the highest you could detect external to the CPU.
"Eve of Destruction", it's not just for old hippies anymore...
I have a small sticker that when applied to your laptop will block all harmful RF energies!!. But wait! There's more! Apply one to your gas tank and you'll see a 30 horsepower increase!! as well as getting an extra 15 miles per gallon!!
How much would you pay for this small miracle? Three hundred? Two hundred? NO! Today only I am ready to sell you this modern wonder of technology for a mere six payments of $19.99!!!
Act now! Operators are standing by!
tard
and might emit a few microwatts at best. The plastic case should stop that. Microwave ovens on the other hand are just a modern RF oven. You dump 800 watts into a cubic foot steel box, something is going to absorb that energy and convert it to heat.
Only the State obtains its revenue by coercion. - Murray Rothbard
In same safety stores you can buy a plastic card that when held to a microwave will show you the amount of leakage. Just test your laptop with this. But I don't think you will see any microwaves coming from your laptop unless you have wifi card.
Hold an otherwise operational wireless bicycle odometer near your laptop. Watch your speed ... you just might get a ticket ;-)
To-do List: Receive telemarketing call during a tornado warning. Check.
What better slasdot topic can there be? "Imagine a beowulf cluster of DNA emitters which don't overheat..."
I forget what 8 was for.
Have you considered wrapping your lower body in tinfoil?
If your 2.4 GHz CPU put out any significant amount of microwave radiation cordless phone and WiFi users surely would have noticed by now.
Something related from a previous (ask) slashdot story.
Well, isn't there a metal heatsink covering the CPU? The tiny amount of microwave radiation would be absorbed by the metal heatsink unless I am missing something here.
I got this far in the article you linked to:
...and sorta lost interest.
Hertel not only conceived of the study and carried it out, he was one of eight participants. "To control as many variables as possible, we selected eight individuals who were strict macrobiotic diet participants from the Macrobiotic Institute at Kientel, Switzerland," Hertel explained. "We were all housed in the same hotel environment for eight weeks. There was no smoking, no alcohol and no sex." One can readily see that this protocol makes sense.
The full scrotal Faraday cage.
September 2011: Looking for Cocoa/iOS work in Boston area Cocoa Programmer Quincy, MA
Here's a cup, a magazine, and a wet nap. Don't spill. If you use Viagara, make sure you use adaquate eye protection. If it comes out green, call me in the morning.
Informatus Technologicus
However, it's a known fact that the mechanics of microwave cooking are fundamentally different from traditional cooking
No, it's not. Like all forms of traditional heat-utilizing cooking, you heat up the food at some place, which heats the rest of it.
Frying, baking, boiling, steaming, etc, all work like this. Microwaving, instead of heating the surface of the food, heats all of the water molecules within the food. This is exactly the same as if you had a knob and could change the temperature of the water without changing the rest of the food in any way. Any notion of "nutritional" changes are highly suspect. There's just no reason to believe microwaves, for example, could significantly change the vitamin or mineral content of the food.
Microwaves are non-ionizing radiation. That means, roughly, that they don't knock atoms into pieces, and thus don't break atomic bonds. They just heat up matter, especially water, since water absorbs microwaves so well.
Some label this pseudoscience.
That's because it is. There's no valid scientific observation, and no logical scientific model, to suggest that microwave radiation directly affects the nutrition in food.
Just because microwave ovens seem more magical than a frying pan does not excuse them from the rigors of science or the laws of reality.
Actually, microwaves /do/ have more of an effect on the nutritional contents of food, especially vegetables. Traditionally, you cook vegetables in water. Microwaves get the temperature of the vegetables well above what it would be even boiling, and the higher the heat (and the addition of water by itself) means that microwaving vegetables loses more than 95% of the nutrients. Boiling loses about 90% for comparison. Letting it sit in cold or room temperature water loses 80% by itself, before any cooking occurs.
Look into WiFi or mobile phone. These actually do transmit RF at > 1GHz.
Actually, microwaves /do/ have more of an effect on the nutritional contents of food, especially vegetables.
... microwave cooking ... induces molecular changes to the food that may be harmful to humans ... the mechanics of microwave cooking are fundamentally different from traditional cooking
No, they don't. Microwave radiation does not affect food nutrition.
I wasn't addressing whether boiling or microwaving vegetables are equally healthy. I was addressing microwave radiation.
Re-read the poster I was replying to:
Of more concern
So you bring up numbers (bogus sounding numbers at that*) that say boiling a vegetable is a little worse than setting it in water, and that microwaving it is slightly worse than that. Big deal. It's not magical molecule transforming rays doing it, it's just heat. Same with frying, baking, flame broiling, deep frying, stewing, etc.
In other words, microwaving food is in the same realm as "traditional cooking", contrary to the pseudoscience the poster promoted.
You are bringing up an entirely different point, which is whether microwaving vegetables or boiling vegetables is healthier. Something to ponder, if you really care about a 5% nutrient difference, but entirely separate from the question at hand.
* 80% nutrient loss by setting a vegetable in cold water? Maybe if you mash it up, and set a small portion in a big bucket of water for a few days or something. Or maybe if you place a sliced apple in water for a half hour. How much does deep frying lose? I bet it's more than the supposed 15% in the microwave.
Beyond that, the numbers are too round. Is it 92% for boiling, and 93% for microwave? Or did it actually come out 80%, 90% and 95%? Are you under-boiling, but over-microwaving? What vegetable is it? Etc.
You guys are writing this off a little too quickly IMHO. I never thought about this before but I just looked across the spectrum at my Gateway 600 and....wow! It's no 40 Watt transmitter but it's sure putting out far more that I would have imagined.
I also looked at my cell phone and my Uniden cordless phone, they don't compare. Those devices are pretty focused whereas the Gateway notebook is putting out lots more energy and across more of the spectrum. This thing is like a shotgun.
. Quit playing Monopoly with Bill. Switch to one of many non-Microsoft products today.
I used up all my sick days, so I'm calling in dead.
http://www.cspinet.org/nah/04_05/microwavemyths.pd f
This was in the "Nutrition Action Health Letter" from the Center for Science in the Public Interest a few months ago. Its a very reputable publication (I recommend a subscription for anyone that tries to eat healthy).
Did you read the articles you're using as evidence?
After all, how could you tell about subtle changes in a human's blood from eating microwaved food if smoking, booze, junk food, pollution, pesticides, hormones, antibiotics and everything else in the common environment were also present?
In other words: the study was very theoretical, and environmental factors affect humans much more than anything a microwave can do to the food.
That's why there was a gag order against slander. The study wasn't meaningful and was just fearmongering. If there was any real meaning, they could've used the truth defense against slander in half a second and gotten the gag order lifted.
"High-pressure boiling, low-pressure boiling (conventional), steaming and microwaving were the four domestic cooking processes used in this work . . . . [W]e can conclude that a greater quantity of phenolic compounds will be provided by consumption of steamed broccoli as compared with broccoli prepared by other cooking processes."
So the only process that's significantly different is steaming. That means that microwaving is as bad as boiling. Is boiling now somehow "fundamentally different from traditional cooking" too?
As an amature you will be hard pressed to measure radiation in the 2.4 GHz band. (Microwave is anything beyond 1GHz BTW.) You would need a good HP scope with high impedance probes that probably costs 100K. Better engineering universities will have this equipment. Some university profs are actually geeks so they might be willing to help if you ask nicely.
As others have pointed out the radiation level will be quite low. Various standars have required low EM radiation.
True, however, the rapid, high heat that microwaving can cause can cause chemical reactions in the food (conventional cooking does, as well).
... induces molecular changes to the food that may be harmful to humans" is, in fact, true. The problem is that the context is compared to "traditional cooking".
Exactly.
The question at hand is whether microwaves do something unnatural to food, as compared to "traditional cooking".
They don't. Yes, microwaving food is unique in the "signature" it leaves, but so it steaming, boiling, broiling, frying, baking, etc. It's fully in that same realm. It's *not* in the magical and scary realm that the original poster placed it.
The actual microwaves themselves do nothing except heat up the molecules that best absorb them. Beyond that, it's the normal mechanics of cooking--you heat something, and it heats the somethings around it, and the food cooks.
This isn't a debate on whether microwaved food tastes better than fried food, or whether it's healthier than steamed food, it's whether microwaving is the same basic process as the whole of "traditional cooking", which it is.
I suspect you are missing the context. You (I think) are trying to point out that the original poster's point that, "microwave cooking
That cooking food (including microwave cooking) changes the molecules is not in question. That microwave radiation does evil, non-natural things to food is.
I guess now we know Geordi posts on Slashdot.
Imagine the day when 40 THz cards might become the norm. Governments and select, exclusive cliques can sell such card at rock-bottom prices or maybe even for free.
This could become the beginnings of a new kind of social genocide (hmmm, a new misnomer?), much like a revival of the purported (or real) government quest of the 70's to find the right molecule to knock of black Americans.
Imagine if it were possible to selectively tune these things such that they don't interfere with residential and emergency services electronics gear or pacemakers and the like. Now, you could peddle these Wi-Fry cards.
But, wait: even better would be the capability to put a clamp (like a sperm-kickin' boot up the ass) around the ankles of registered (assume the unregistered have yet to be discovered and dealt with) sex offenders. These non-sexy anklets could be the near-equivalent of parking enforcement boots for cars, except the house-arrested offender could have his/her, ummm, I mean HIS sperm "neutralized". Well, you could cut his nuggets out and dispose of them, but then if he were an accused and not a confirmed assailant, and were later exonerated, taxpayers would pay out the ying-yang unless the governments were allowed to claim "right of government in the interest of public safety...".
But, then these Teste-Fry bracelets and anklets would protect potential victims from being inseminated. In fact, selling Sperm-Killing emitters might be a way for women to neuter bastards who don't know the meaning of "No!/Stop!". These little anti-jewel emitters could be used without the need to make the man take the male pill, done discretely, and help the woman avert the side-effects of taking the various Pills, RU486's and dealing with IUDs, cervical caps and the like (from an insemination/impregnation POV, not from an anti-HIV/STD point of view).
Maybe whole networks of these things might someday be set up around poor neighborhoods. With the right funding, maybe someone will figure out the right Anti-Verility Frequency for whole communities, used in conjunction with school lunch plans, weather control, and the like.
Hmmm, either I'm onto something (or a few things) or it's just late...
> Did you read the articles you're using as evidence?
.
I read up on the older Swiss work several years ago. A gag order for it is just stupid.
This is just a recent link I found with Google that references it.
I didn't read the second paper, just it's abstract, which you quoted:
> "High-pressure boiling, low-pressure boiling (conventional),
> steaming and microwaving were the four domestic cooking processes used in this work . . .
> [W]e can conclude that a greater quantity of phenolic compounds will be provided
> by consumption of steamed broccoli as compared with broccoli prepared by other cooking processes."
> So the only process that's significantly different is steaming.
> That means that microwaving is as bad as boiling.
No.
Sure you can comprehend differences in this paragraph from the abstract that you missed quoting:
Clear disadvantages were detected when broccoli was microwaved, namely high losses of flavonoids (97%), sinapic acid derivatives (74%) and caffeoyl-quinic acid derivatives (87%). Conventional boiling led to a significant loss of flavonoids (66%) from fresh raw broccoli, while high-pressure boiling caused considerable leaching (47%) of caffeoyl-quinic acid derivatives into the cooking water.
Fertilization!
Just have unprotected sex with your life-partner[*] as often as possible for the next 10 years. Observe whether the rate of her pregnancy goes down over the years.
This is in no way a valid test, nor will it reveal anything about the laptop, but it'll be fun in the process, and you'll be able to claim its all in the interests of science!
[*] Usual rules regarding STDs and ensuring you and your life partner stay true to each other, no nipping off to the local establishment to perform other not-so-valid scientific tests with other, um, subjects.
I use to have a funny sig, but slash cut it off, and I forgot what the punchline was.
So, considering that you don't want to have your laptop on your lap, since it emits heat, why worry about microwaves damaging your "equipment".
It's like saying "I am planning on ignoring this advice about the heat, but I'd like to know if there are even more threats to my health".
My advice, don't put your laptop on your lap, treat it like a portable desktop instead. You'll be fine.
As well as the occasional Mancunian.
-I like my women like I like my tea: green-
Been thinking about it for long.
;D)
I have a CRT and non-grounded outlet.
I know the shieldings only work when grounded, but then I also have no idea if it matters with the radiation.
What is emitted and is it dangerous?
Should I care?
Should i get a TFT immediatly? (please say yes
I could use a cord from the kitchen but uhm, no, that sucks, but I don't want to get hurt by this monitor either. Please help. This is leeloo speaking.
no but if you heat them enough you might gets some gamma rays out of them. 10 million degrees ought to do it
I hate to say it, but the Ghz for computers and microwaves are both measuring things in per second, but they're measuring different things. The 2.4Ghz in a computer means 2.4 billion operations per second. The 2.4 Ghz for the microwaves means 2.4 billion oscillations of the photon per second. Wait, I just realized that this is Slashdot and you all know this already. Well, at least it's out there.
Sorry mate, but clock speed (Hz) doesn't actually directly relate to operations per second. Case in point: the first Intel P4s were clocked higher than PIIIs but performed less opertions per cycle, and were in fact slower than the PIIIs!!! Also the reason why Athlon went to the "Performance Rating (PR)" instead of using raw clock speed.
"They looked deep into my soul and assigned me a number based on the order in which I joined"
On the other hand, there is evidence that more mundane cooking methods are more dangerous. Barbecuing meats or any other organic matter can create benzopyrene which is a potent mutagen and carcinogen. Even burning toast (like in a toaster) has been found to produce the dangerous chemical. Now, none of the scientists involved in these studies are telling people to stop grilling food, and stop having burnt toast for breakfast. Of course, some groups have taken those results and used them to further their agendas. I've seen a repeated claim that a grilled steak contains as much benzopyrene as 300 cigarettes (which is supposed to make you believe that a grilled steak is as dangerous as 300 cigarettes, except the soundbite never mentions that cigarettes contain many other toxins and carcinogens). While it's strictly true, it's neither useful, or helpful.
Even vegetables that are cooked to higher than 120 degrees Celcius can form the carcinogen acrylamide. No one calls for us to renounce bread, nuts, french fries, and coffee. At least I didn't find any immediate results for that (I guess militant vegans [as opposed to the sane ones who can accept other people's food preferences] aren't eager to lose some of the few foods they are willing to eat).
Now, microwave cooking can not cause the first toxin to form (because it requires incomplete burning of fat and oils at 300 to 600 degrees C), and it's unlikely that it can cause the second to form either (deep frying and roasting tend to cause it). That must make microwaves safer than conventional cooking, right. :-P
I used up all my sick days, so I'm calling in dead.
Get yourself a zapchecker
Mine shows some radiation form my computer.
It's not magical molecule transforming rays doing it, it's just heat.
Well, I'm not a microwave engineer, but iirc the microwave oven creates standing waves of microwaves within the "cooking cavity" (for want of a better term). These standing waves induce water molecules in the substance being heated to oscillate, thus heating it.
So yes, it is just heat, but the method of transferring the energy to the thing being heated is unique amongst cooking methods.
Incidentally, it's this that is repsonsible for uneven heating, and why you should stir things and/or leave them to stand - the wavelength of microwaves is on the order of centimetres, so the nodes of the standing waves generated are a centimetre or two apart. At the node, very little or no heating occurs, as no oscillation is induced. Thus you have to stir the thing or leave it to stand to even out the heating.
Finally, intense enough EM radiation can cause ionisation of the substances it passes through, but at microwave energies any such ionisationwill be utterly insignificant, if it occurs at all.
It's official. Most of you are morons.
WiFi transmit power for almost all cards is 25 mW. 100 mW is the max legal limit without using automatic power control measures (reducing power when it's not needed) The max legal limit for WiFi is higher (There are even 1W amps), but 25 mW is the max from almost any laptop, and anything more than 100 mW without an external PA is unheard of. (I know of one card in existence that had transmit power over 100 mW)
And as to stray emissions from the laptop itself - WAY less than the 1/10 W (100 mW) you mentioned, guaranteed. Almost surely less than 1 mW. There's no way the FCC would approve any device that was an interference source with 100 mW transmit power. Hell, 1 mW of unintended emissions is probably not allowed. RF-wise, computers (especially laptops) are very quiet.
retrorocket.o not found, launch anyway?
> > However, it's a known fact that the mechanics of microwave cooking
> > are fundamentally different from traditional cooking
> No, it's not. Like all forms of traditional heat-utilizing cooking,
> you heat up the food at some place, which heats the rest of it.
You are wrong.
When I cook something in normal fashion, I can be sure that the temperature of the food is BELOW the temperature of my heat source - the grill, open fire, oven, steam, etc. Not so with microwave cooking - I can't reliably estimate temperatures reached within the food. Certain parts of the food can reach temperatures never attained in normal cooking (since the food as a whole would be destroyed at those temperatures.) Localized reactions can generate harmful compounds at such temperatures, which would be masked by the taste of the bulk of the food.
If you think this cannot happen, that's just an article of your blind faith. As for me, I know the cheese in my pizza tastes funny when I reheat it in a microwave.
And that's just the thermal effects of microwave radition. There is growing body of evidence for non-thermal effects: see interesting opinion here and a summary mention here that says: It is clear, though, that nonthermal effects do play a role in some reactions.
Actually, having brushed up on my reading, let me correct the subject of my thread - I WOULD worry about the laptop, but perhaps more on where the built wifi antenna is positioned.
The 2.4GHz clock is generated inside the CPU, multiplied up from the external clock by a PLL. A few microwatts may get out, but it's just RF. All it can do is heat things up. Your balls are already being cooked by conducted heat, so don't worry about the RF.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
There's one other major cause of fertility problems, oestrogen like molecules.
There are two key sources for absorbed oestrogen like molecules, pollution and soya.
A just to make sure you get all the bang for you buck, they also causes birth defects.
thank God the internet isn't a human right.
To be sold in the US, the laptop has to pass FCC certification- there are similar requirements for every other country. The FCC requires that emissions be below a certain level, so that they don't interfere with legitamate users of the airwaves- so there has been testing that has shown that the power level out is pretty low (usually in the microwatts or lower).
But the biggest reason why I wouldn't be concerned is simply the conservation of energy- all of the energy in the laptop is consumed some way- ultimately as some sort of EM radiation (RF out, light out of the display, and heat) Laptop makers are extremely concerned about battery life- if you were transmitting 40W of power as 2.4GHz RF- that's 40W of power that wouldn't be consumed by the CPU- and that much less total operational time while on the battery.
Case in point: the first Intel P4s were clocked higher than PIIIs but performed less opertions per cycle, and were in fact slower than the PIIIs!!!
Care to back that up with a source?
If VISTA is the answer, you didn't understand the question
The Pentium 4 performs much less work per cycle than other CPUs (such as the various Athlon or older Pentium III architectures) but the original design objective - to sacrifice instructions per clock cycle in order to achieve a greater number of cycles per second (i.e. greater frequency or clockspeed) - has been fulfilled http://en.wikipedia.org/wiki/Pentium_4
And in case you aren't satisfied with that:
As early as 2000, THG observed that the Pentium 4's performance was clearly inferior to that of its predecessor, the Pentium III, on a clock-for-clock basis. http://www.tomshardware.com/cpu/20050525/
There are a ton of other sources, just try googling...
"They looked deep into my soul and assigned me a number based on the order in which I joined"
Science: fun and delicious!
1 Hz = 1 cycle/second
2GHz = 2.4 billion cycles/second
The GHz is measuring EXACTLY the same thing
Just FYI, the skin depth of a 2.4GHz EM wave should be on the order of 50nm - the heat sink alone should be more than enough to stop virtually all microwave radiation from your laptop
My question is this... are his veggies traceable to the NIST standard?