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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...
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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.
Have you considered wrapping your lower body in tinfoil?
The full scrotal Faraday cage.
September 2011: Looking for Cocoa/iOS work in Boston area Cocoa Programmer Quincy, MA
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.
... 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 guess now we know Geordi posts on Slashdot.
I am one of the prof geeks you refer to, who works at a University and we do have the equipment to test this (ie 7GHz Spectrum Analyser), and we did exactly that when the first P4 2.4 GHz CPUs appeared a few years ago. We built an antenna tuned to the correct frequency, hooked it up to the Spec An, turned it on, pulled the case off, put the antenna in and we got... nothing. Not a peep. Zip. Buck all. This was as we expected, but we thought we'd do it anyway. So you can all put your conspiracy theories away! ;)
"They looked deep into my soul and assigned me a number based on the order in which I joined"
Get yourself a zapchecker
Mine shows some radiation form my computer.
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"