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59

Inside virtually every phone charger is a transformer. Transformers have a finite resistance, and hence there will always be current flowing through them if they are plugged in, even if there is no load (i.e. nothing charging). That's basic physics. But the obvious follow-up question is: how much energy does it use? Estimates vary, but its certainly not ...


42

UPDATE: I just read an excellent article which discusses the WHO review. I thought it good to add the link as some have interpreted the WHO's addition of cellphones to Group 2A (Probably carcinogenic to humans) status to be "conclusive evidence". The May report from the IARC moved cell phones from Group 4—probably not carcinogenic—to Group 2B, or ...


41

In this Green Monk article, it is shown (with an ammeter) that most chargers idle between 0 and 0.1 watts. The mobile phone chargers I tested all consumed 0.1W or less of electricity when left plugged in and not charging a phone. That is minute. It contrasts that with other devices. Well, my microwave consumes 3.5W when plugged in and not in use (...


38

I would say this is Not True Just going by the sentence you’ve highlighted: Health experts believe this increased exposure to 5G will have a devastating impact on our health. It’s already doubtful. Who are these so-called “health experts”? Why do they believe this? If we look at the National Cancer Institute's page specifically for cellular RF and its ...


37

Microwave in the microwave oven is usually at 2.45 gigahertz http://en.wikipedia.org/wiki/Microwave_oven#Principles Wireless LAN protocols, such as Bluetooth and the IEEE 802.11 specifications, also use microwaves in the 2.4 GHz range http://en.wikipedia.org/wiki/Microwave#Communication So using Bluetooth / WiFi is a very good test for seeing if the ...


34

Norwegian science journalist Gunnar Tjomlid published an article [Norwegian language] in the online newspaper Nettavisen. Blogger Pepijn van Erp summarised it in English. In brief, the experiment was not properly controlled, not blinded, had publication bias, was misreported, had faulty statistical analysis, had bias in the methodology and relied on a ...


28

The radiation is 1000 times stronger According to Wikipedia The transmission power of a GSM handset is limited to a maximum of 2 watts in GSM 850/900 and 1 watt in GSM 1800/1900. According to a Radio-Electronics.com article "GSM Power Control and Power Class" the base station controls handset power output in the range 2-19 which is 39 dBm to 5 dBm. ...


26

According to HowStuffWorks' page on How Remote Entry Works: The fob that you carry on your keychain or use to open the garage door is actually a small radio transmitter. When you push a button on the fob, you turn on the transmitter and it sends a code to the receiver (either in the car or in the garage). Inside the car or garage is a radio receiver tuned ...


24

Simple calculations suggest this story is nonsense. I'm not an expert in radiative physics but I can see from simple calculations that the story has strayed beyond the bounds of plausibility. The first, very simple, calculation is to look at the total power used if 200 mobile phones (a very full train carriage) were being used at the same time. I'm going to ...


23

Yes, but not in a way that is likely to detect Ghosts if they exist Mobile phones are, by definition, devices that can detect EMF (which is electro magnetic field see wikpedia) since their ability to communicate depends on radiofrequency fluctuations in EMFs. So apps on a smartphone can, at least in a trivial sense, detect EMF and alter it when they send a ...


22

The Local (Swedish news in English) reported in 2009 on a study that has gone over 30 years of brain tumor history in Scandinavia offering the following summary (in a more readable format than the actual papers abstract). Even though mobile telephone use soared from the 1990s , brain tumours did not become any more common, the researchers reported in the ...


21

This site calculates the use, in 2013, per year of your phone: How Much Electricity Do Your Gadgets Really Use? (Forbes, 7 sep 2013) It comes down to about 2kWh/year, assuming one full charge per day. This site gives typical wattage for different appliances, and allows you to calculate annual usage based on hours/day and days/year the appliance is used: ...


20

While the answer from @manojlds was reasonable, I wasn't satisfied. The key question is not whether the seals on a microwave can be tested using Wifi at the same operating frequency (2.4GHz), but whether a cell phone is an accurate way of testing these same seals. In other words, will something that filters out 2.4GHz also filter out 900-1800MHz? I did my ...


18

Back in 2012 this probably wasn't answerable, now after Gazelle's research which was conducted in 2014 I can attempt to answer this. The good news: it prevents it from dying. The bad news: it isn't the most effective (more like least effective). Gazelle, an eCommerce company, which lets people sell their used cell phones and pays consumers for used or ...


17

On that related question, there was a deleted answer that stated the following (All that follows is a direct copy/paste from that deleted answer): The study they appear to be referencing for their statement is "Effects of Electromagnetic Radiation from a Cellular Phone on Human Sperm Motility: An In Vitro Study" (Erogul, Oztas, et, 2006, source) To ...


17

Problem 1: "Table 1. Publications which reported positive findings on oxidative stress caused by RFR exposure of cellsin vitro." Problem 2: "Table 2. Publications which reported positive findings on oxidative stress caused by RFR exposure of animals and plants." Problem 3: "Table 3. Publications which reported positive findings on oxidative ...


17

The pictures are not fake. They are real photos of a phone baked into a cake, and then removed. However, the "Imagine this scenario. You drop your phone..." text is just imagination, not what actually occurred in making the photos. The photos are frames from the video iPhone 5S Baked In Cake - Will it Survive?. In the video, the narrator, TechRax, ...


16

It depends upon your definition of "off", "track", and "phone". Some phones will keep the baseband chip powered when the device has been shut down. In some cases, security agencies have "updated" the baseband sofware on a large number of phones in order to make them trackable when shut down. It's certainly possible to install OTA updates with almost ...


15

The trick for detecting a 2-way mirror is not 100% reliable, but is not entirely wrong either. Two-way mirrors intended for observation are made using dark ("smoked") glass (/acrylic/whatever), with a partially-reflective coating on one side. Critically, the reflective side is installed toward the subject (i.e. the one being spied on). The reason for this ...


15

Yes, WiFi is significantly more efficient, as the protocol is completely different. Once association with access point is established, WiFi only uses energy for actual transmission of data. On the other hand 3G remains in high-power state even after transmission is done. source: "Energy Consumption in Mobile Phones: A Measurement Study and Implications for ...


15

Link between Cell Towers and Cancer Elusive A quick search on cell phone towers and cancer provides many results, some state cell phone towers are dangerous because it can cause cancer, while some others state that tests regarding cell phone towers and cell phone usage are inconclusive with regards to cancer, though there are chances of increased risks in ...


15

GSM Association in 2013 has published white paper, which strongly suggests that there is no evidence proving any reduction in crime or terrorism. The Mandatory Registration of Prepaid SIM Card Users Excerpts from summary: An increasing number of governments have recently introduced mandatory registration of prepaid SIM card users, primarily as a ...


14

This was tested and busted by Mythbusters. It is also listed as urban legend / email hoax by About.com. The signals emitted by the car remote are mainly radio signals with a frequency of 315MHz in the US and Japan and 433.92MHz (ISM band) in Europe as explained in Requirements of Remote Keyless Entry (RKE) Systems. An alternative are infrared remotes which ...


14

It's possible, but unlikely. It's possible Cakes cook from the outside in. If you are not careful you might pull out a cake cooked outside but raw inside. This happens when the oven is too hot. What to do if my cake seems ready from the outside (it's brown as it should be) however it's not done yet inside? [...] If you find that your cakes are ...


13

This question reminded me of the xkcd what-if post which mentions that "If an unused charger isn’t warm to the touch, it’s using less than a penny of electricity a day", but without references. Searching more I found the reddit thread following the xkcd post, which has lots of links, including to pages 68 and on of the free (Creative Commons) book "...


13

This is Enhanced 911 (easier-to-understand Wikipedia article): cell-phone network operators are required to transmit the location of a cellphone with a given level of accuracy to a 911 call center. It does not specifically require the use of GPS, but the accuracy requirements are such that GPS is generally used. Excerpting the WIkipedia page: The U.S. ...


12

It looks like you might be confusing some terms here... using more battery/power doesn't necessarily translate into more or less radiation. The radiation strength is determined by the frequency that the devices operate at, i.e., the frequency of the radiation they emit. 3G devices (in the U.S.A.) don't really have a set frequency, but rather will operate at ...


11

The answer is Maybe, if you have a pacemaker, and then only potentially. Normal people: No as I couldn't find any warnings where I would expect to find them. As I'm not a medical doctor, if you are really worried you should ask a cardiologist. I can not be sued for malpractice (and disclaim liability for my answer), but as professionals they can be held ...


11

These articles state it can be done: Washington Post - NSA growth fueled by need to target terrorists The Atlantic Wire - How the NSA Is Using Cell Phone Data to Drone Civilians (In Pakistan) By September 2004, a new NSA technique enabled the agency to find cellphones even when they were turned off. JSOC troops called this “The Find,” and it gave ...


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