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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.
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...
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.
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.
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).
Get yourself a zapchecker
Mine shows some radiation form my computer.