Can you call a cell phone in the microwave? 

Great, my friend watched this video with me and all she took from it is that the microwave leaks radiation. She completely ignored where you said it was non ionizing and is currently trying to cover the microwave with "protective foil" Thanx Diana. I guess the good news is, after she's done entombing the microwave, she won't have enough tin foil left to make a hat.

Now try a banana and travel through time

I am surprised. I thought microwave ovens would be much better Faraday cages than they actually turned out to be.

revisiting this months later, this is the coolest video.

I remember dragging an HP spectrum analyzer home from work back in the 80's to do this. Most of the leakage was at the door joint. Holding the door tighter there was less leakage so I adjusted it. The internet was a university novelty then, mobile phones were mounted in the trunks of doctors and lawyers and everything over 1 GHz was a small fortune.

Damn, I was looking for 'Psychic Girl'...this is better anyways

Nice work! I really liked the RF investigation. Nice shirt too ;)

I love this video!

i tried calling my cellphone when he was inside the microwave , i didn't get the call and the Wi-Fi was blocked , my microwave is very safe😂

Shoutout for Samy's _Applied Science_ T-shirt! That's how you know he's a cool dude!

With the wifi call, are your sure that the wifi was on 2.4GHz and not 5GHz? The latter is becoming more popular in a bid to find more spectrum.

As an avionics technician, I have performed leak tests on microwave ovens installed on aircraft. When I was performing these tests in the late 80's, EVERY microwave I tested leaked beyond acceptable limits. I was actually surprised to see microwaves that did not leak.

You get a thumbs up coz the guy is wearing an Applied Science t-shirt at 2:20 ... :D

instructions not clear, my phone turned into green slime

2:11 An applied science shirt, nice to see that around :D

I actually work in the industry and we use microwave ovens for testing. It used to be that you could unscrew the antenna and put in a coax cable to connect to the cell hardware but external antennas disappeared. Note that in the US voice calls would use CDMA band classes 1 and 2 at 850 MHz and 1900 MHz (PCS) and sometimes the auxiliary 800MHz range. But for testing LTE data which runs in the GHz bandclasses we place the mobile UE in the microwave and run an antenna wire inside from the eNodeB. This prevents the UE from attaching to a commercial signal and our testing from affecting any users of the commercial signal. We are not allowed to bleed any RF. Another interesting fact is that some high efficiency energy saving windows are very good at blocking LTE radio ranges. So much so that I have seen a demonstration where a mobile was placed less that two feet from from the eNodeB antenna and one of those salesman demonstration mini windows placed between them. The mobile lost communication immediately. So if you are getting a bad signal inside the house doing the "natural" thing of going to the window could be the worst choice to make.

Yeahhh Samy !!! that guy is incredible. Btw the art of electronics spotted ;)

+Physics Girl I love your videos. I have a degree in physics too (from the 70s). Here's an idea for one you could host. We all like our soda to stay fizzy once we've opened it and re-sealed it. We see tops for fizzy bottles with built in pumps in the stores that claim to keep the drink carbonated by pumping air into the bottle and pressurizing it. But they don't. The Partial Gas Law tells us that the presence of air (mostly Nitrogen and Oxygen) doesn't affect the pressure of CO2 at all no matter how much of it there is in the bottle. The CO2 ignores it completely. And the amount of CO2 in air is only 0.038% so pumping up these devices adds virtually no CO2 to your drink. And it's dissolved CO2 that makes your drink fizzy and nothing else. So the only way to fizz up your flat drink is to add CO2 directly with a Soda Stream machine, a bit of dry ice or... I don't know. Any ideas? I thought of submitting this idea to Mythbusters but haven't.

Good job pointing out the confounding variables.

What I appreciate most in the video is the the final discussion about bias in the observation and the sample was not homogeneous in the other characteristics :)

Wait... logo from Applied Science channel ?

I can see the classic "Art of Electronics" book in the background

By pure coincindence, this video came out when I was watching Stein Gate.

Interesting to see those experiments really done. Thanks! The reason WiFi was getting through better than cellphone signals could be that the cell tower was a lot farther away than the WiFi access point. Even though cellphone towers emit more power and have better high-gain antennas (they radiate most energy horizontally and only a little bit upwards -> poor reception in airplanes), the inverse-square law means the it is likely that a lot less less cellphone tower field intensity was arriving than WiFi field intensity.

Explains why I turn green when I get angry and wake up naked.

+Physics Girl Note that Wi-Fi also uses the 5GHz band. If his wireless router supports it, the facetime call could have used 5GHz, not 2.4GHz thereby penetrating the microwave.

*accidentally create a time machine

It's possible your iPhone used the 5 GHz wifi signals when it was in the microwave. That would explain why it still received the call when the microwave was (supposedly) blocking the 2.4 GHz signal. Also, thumbs up for the Applied Science t-shirt! :)

The issue may not be between microwaves, it may be the signal strength of the surrounding cell phone towers that your phone is communicating with. To be sure you should gather the different microwaves in the same place, and see if the results are the same.

This video is so great. You started with a solid science concept and really followed it where it took you. Thanks for creating.

Samy Kamkar AND Physics Girl !!! I'm having a ScienceGasm

Beautiful Dianna :) I liked the way yoy went through what you were thinking at each point

This video was unsponsored by carcassonne :) The blur snub of an awesome game!

I really like the way you're approaching the problem. Feels really well structured and eleborated.

Samy is my hero

Thanks for the information. I have read to put one's emergency radio and electronic equipment in an old microwave oven with the cord cut to protect against an EMP, and told to test it in a similar manner with the FM radio band on. Now, I have my doubts. Your test is good for people as a cheap way to check their microwave oven. Thanks. Good luck with your site.

U should turn on the microwave

Nice, book of Art of Electronics over there. At 5:33 the blur of the boxes goes out, lol

One thought: if you considered the microwave oven as an attenuator rather than a perfect cage, you would definitely see a different picture. Your WiFi network is much closer in proximity than the nearest cellular tower and thus your reduction in signal strength might be the same, but still have enough to make it through eventhough the emitted signal strength from the system is lower. I think a great experiment would be with 2X hack RF modules communicating and measuring signal strength at different frequencies. Give it a try and let us know what you find out. As an RF guru in the drone World, I find this stuff very fun!

Years ago, I powered up a radar detector with a power adapter and tested to see if it would pick up a signal from the microwave. It did. It showed up as X band, which was around 10 GHz.

Oh, so you love microwaves too ♥

6:56 the two blurred boxes unblurred

Thank you physic girl! (That's the closest I'll ever get to thanking a super heroine)

One important variable not accounted for is fading. RF signals that travel through the air experience significant reflections off the ground/houses/walls/people/furniture/etc. These reflections creating interference patterns as the reflected signals add and subtract and these patterns change dynamically as the "environment" that the signals travel through changes. The interference patterns are very small in scale, where moving the phone by a few inches in any direction can create massive changes of 20 dB (a factor of 100) or more in received signal strength. A person moving, or leaves rustling on the trees outside create dynamic changes to the environment. The implication is that whether a certain microwave allowed a call to ring or not could be simply dumb luck related to the dynamic environment of the RF signals travelling between the phone and tower. The "Faraday cage" of the microwave oven is by no means perfect. Since the metal if the microwave box is not a perfect electrical conductor, there will always be some signal leakage, but it does act as a very good attenuator of the signal (60-70+ dB). Depending on the signal strength available outside of the oven (which has to do with many factors including distance to the tower, presence of trees foliage, ground topography, building materials used in the house, the RF fading environment discussed above, and more) the signal strength inside the oven will be 60+ dB less. Whether the phone rings or not in a given environment is the result of all these complex signal strength factors. A better (but more complex/expensive) experiment would be to set up a signal source of a known strength inside of a microwave and then take measurements of the strength outside of the oven in a controlled environment such as an antenna range. You could also measure it versus frequency to see how it changes over common cellular frequencies.

Stein; gate, anyone?

I was just about to test this but my phone was dead.... so I searched YT and got you. SAMMY KAMKAR IS IN THE HOUSE! He's my hero!

actually, you had some variables you didnt account for... 1 : Cell Towers. The RF energy does not go from phone A - to Phone B directly, it goes through a tower first. so, this can be the difference at peoples houses, who may have lived different distances from different towers. and dont forget, there are 2 different links. 1 from the first cell to the tower 2 from the tower to the second cell no information or energy is transmitted between the 2 cell phones directly. 2 : line of sight. RF in this range is pretty much (but not totally) line of sight. so, if the door of the microwave is pointed toward a large open window it may have a better chance of working. if its pointed away, and its a small window, or, in a room in the middle of the house it may not work at all. Signals can bounce off of hard surfaces, but get less each time. think of going into a room with no lights. if the door is open, you can still see, but, its not as bright and this is coming from a tower blocks, or , miles away. cheers, Brad senior RF design engineer. Sprint PCS (retired)

OH GOD THIS EXPLAINS A LOT OMG. I used to work somewhere with a walk in freezer and if i had my phone in my pocket it would lose signal when i went in the freezer but come back when I came out. It also blocks wifi signal so if you were trying to get wifi and standing on the opposite side of the freezer from the router you couldn't get signal. Amazing!

You have a ton of friends with microwaves? I'm jealous.

I'm glad you mentioned the position, orientation and distance away of the microwave from a cellphone tower, because it makes a huge difference. Cellphones can tolerate variations in received signal power of around 60dB which is a factor of one million. So an oven allowing a millionth of the signal in from a really close tower might be the same as no Faraday cage at all if the tower is at extreme range. Still it's mlldly worrying that any measurable amount of 2.4GHz energy escapes. Thanks, I enjoyed it. Bill Dixon

Microwave ovens use "larger" forms of microwaves to cook food than the types of waves used by most cellphones. The Faraday Cage the surrounds the microwave's interior is designed to keep the microwaves inside the oven. But, if your phone uses the "smaller" waves by most phones they can pass into the microwave because the cage isn't usually designed to block them.

The first Faraday cage I built up (microwave) Did Not Leak RF radiation. I could not afford Samy Kamkars Faraday glove box 2-3000$ plus cost of Tap through inter face devices. You and Samy did a great job using test equipment, and multiple tests on different devices. The door is the weakest link on a fridge. If the door seal is ripped, or the latch is not tight the milk will spoil. Thanks for science and not opinion.

a car is also a faraday cage, but you can call a cell phone in it :))

Try the dollar bill test. Put a dollar bill half way in and half out close the door see if you can pull it out. Move it around usually it is a place where the seal is not complete. As always fabulous explanations. Thank you.

The title of the video was very hard for me to read for some reason

When i make popcorn with my wireless headphones on, my wireless headphones lose their light of my computer until i walk away from it.

Oh, the holes in this video, bigger than the holes in a farday cage; what you have made into a video is unnecessarily worrying... The distance between the tower and the microwave makes a difference, a big difference. The faraday cage would create loss in the signal path, if it is communicating with a nearby device or tower, there is more signal that can get in. Quick science & maths time: if my microwave puts out 60dBm (1000W), to get that down to 5mW (7dBm) I only need to loose 53dB, which is well within the -120dB sensitivity of a regular cellphone. WiFi is another example, my router puts out 20dBm, take away 53dBm equals -33dBm, which should be plenty enough to get through the microwave door (at close range).

Very nice, and I think you got to one of the issues at the very end. the space between The grid matters. We are not dealing with inductive electric currents, we are dealing with electromagnetic radiation. The ratio of the grid openings and the frequency of the microwave radiation matters. Certain fractions of the frequency will block, and other fractions will allow passage. So you can have frequencies very close to the blocked frequency getting through.

*No timetravel?*

Thanks for the fun, hands-on look at microwave radiation. The Faraday cage ‘thumb rule’ is not hard and fast. It’s much more complicated. The screens are much more like filters with attenuation of wave propagation than a gate that stops frequencies of smaller wavelength. The classical picture is the wave equation with modes, and the quantum picture includes electron-photon interactions.

Your video is awesome but the title isn't quite appealing.

I thought it was the amplitude of the waves that determined whether or not they got through, not the wavelength. I learned something new today!

That Faraday cage explanation was bogus. A car is a Faraday cage too, yet you can still place calls while you're in a car. -__-

great video!! shared many times on facebook!! well done!

Samy & Dianna, best team ever. I love Samy's channel for all of his infosec, and Dianna's for science. Surprise surprise to see them both. Also way to represent the hackrf! Great video.

A large part of why your phone will ring in some ovens vs others is due to your location. If you are near a cell site, you have a stronger signal so the attenuation of the oven cavity isolation isn't enough to prevent communications. This is likely why you got a Ring with the WiFi calling even though it is at the frequency that the oven cavity is supposed to block, the WiFi signal level was much higher where the oven was located. I did some testing with my oven and I found that I get about -42db attenuation into the cavity with the door closed at WiFi channel 6. Remember that no shielding of anything is 100% and 40 db is a ton of isolation. Yes ALL microwaves will leak!! In the case of my oven, if you assume 700 watts of RF in the cavity and -42db isolation that means that ~44mw are leaking. That is about 1/4 of the RF power from your cell phone that you hold to your head!! And with RF remember that the field strength is reduced with the square of the distance. Even if you hold your head against your microwave, you receive far less RF radiation then from your phone. Funny how us humans fear things irrationally yet hold no concern for something like our phone which exposes us to much more radiation...

hello, the grid is frequency selective. The hols work like radiating apertures. higher the frequency is greater is the leackage as you mentioned. I believe the shielding attenuation is around 35 to 40 dB at 2.4 GHz and this explains why you can still hear the microwaveoven even 20 m away on a special radio tuned to 2.4 GHz, or on a spectrum analyser.

Thank you so much for addressing this issue. This one has always made me wonder. That and the glue on cans when you use a can opener.. but that will be another day I hope to learn about.

Electronic engineering rocks, it's my profession. 23 years telecom. We used to just build leak detectors checking the door seals. Good job.

Physics Girl, you should look into wave guides and the size of the opening to let a freq through. Before I saw the video, I guessed that the phone would still operate in the microwave as you discoveted. The reason for my hypothesis was the theory behind wave guides and the size of the openings of the "mesh" on the microwave door.

Cool video, but when I saw the title I was expecting more of trying to call it as your microwave your phone. Now that would be awesome.

Samy is the best (your garage door opener is in trouble!). Cute, Horowitz & Hill on the book shelf!

I know this won't get answered but I like it when you and veritasuim combined shows y'all 2 could put your minds together and be awsome

Used to work for enterprise level wifi company, can confirm that if people are experiencing few minute wifi outages in the middle of the day, the first thing you check is how close they are to the break room and if there's a microwave in there

very good work on microwave, as I think the small holes grill help the phone for passing the microwave. These all depends on the type of the frequency.

Dear Physics Girl: I do not know if you in fact edit your own videos, but if you do, heres a tip. when trying to blur stuff out, make sure its actually fully blurred and not just half blurred. and and in your software when you add a transition like a fade, the blur goes away earlier than the video itself. (I am referring to the moment at 04:35 as an example of this.) other than that i enjoyed this video. have a nice day. cheers.

Information is "lighter" than mass. A microwave's defenses are intended to prevent gross effects to outside masses, not to obliterate all information. As Mr Universe put it: "You can't stop the signal, Mal." In the 1980's, we put a Geiger-counter up to the view-screen of a microwave oven, and at a couple centimeters or so, it did register some extra clicks. Beyond that range, it was just background rate. The microwave oven design assumes you won't smash your eyeballs right up against it for hours at a time, and it isn't intended to prevent pure information from being transferred. The distance-squared law works as its own buffer, so you don't get a "star-burn" from being out at night, but you can still see the constellations :)

Thank you Physics Girl :) My suggestion, if nobody else has done so: Measure the leaked 2.45GHz radiation off your microwave oven(s), using Samy's device, as a function of perpendicular distance r from the oven's door screen. The amplitude of the leaked radiation should drop down as 1/r2, and does so very quickly, because of refraction - its wavelength is about 12cm, while the screen's holes' diameter is on the order of 3mm. Then the leakage is so little just, say, r=1cm outside of the oven's screen, that you can put your hand there while using the oven, and wouldn't feel a thing. It'd be cool to see the measurement data, though.

My HF 35C HF-Analyzer (800MHz-2700MHz) goes off the chart (above 2000 microwatts/square meter) when turned on "peak" signal with the range on 1999 microwatts/square meter, with my Cuisinart model CMW-100 microwave cooking. And no wonder, (though I knew it spewed out radiation, I didn't know why until tonight), I just found out that the door on my oven is loose even when it is closed! The leak is so bad that I had some time ago put up a faraday cage in my condo, with aluminum foil wrapped around both sides of large pieces of cardboard. This reduces the radiation hazard dramatically! But I still sit several meters (and even more feet) away from the oven when it is cooking. I think it's time I get another microwave. This oven, which was supposedly a "refurbished" unit I bought used from an appliance sales and repair shop around last December. A true "refurb" would come in it's original box with the owner's manual. But this had neither. What it DID have was a loose screw in the back that required a special screwdriver I had to buy to tighten it. I believe I had actually paid somebody's past due repair bill. My previous unit was a new one from Sears that sold new (in 2013) for $54. After four years, it would cook EVEN WHEN THE DOOR WAS OPEN, despite the FDA standard to have two "failsafe" latches to make sure that never happens. Needless to say, I scrapped it right away. My point is this: the quality of microwaves has gone downhill since I bought my first one new in 1983, which was still working well in 2006, when I gave it away.

hello. 1) cellular towers transmits in different frequencies, it can be 900 MHz, 1.8 GHz, 2.1 GHz, 2.3GHz and more depending on company, 2g 3g 4g and location and country, so in other words in 1 house your phone was connected on 3g at 1.8GHz for example, in another at 4g at 2.3GHz and maybe at 900MHz also.... 2) The distance from your phone and the cellular tower greatly affects signal strength from some pico watts to some milli watts (huge difference) 3) your phone might actually lost its signal and then switch to another band so it can actually get a call like 2g signal, that means also the timing here makes a difference and your are coverage by your provider 4) make sure your microwave is properly grounded, this can also affect results

SAMY!!!! love his work.

you may have missed one thing. A microwave oven puts out about 1000 watts of power where a cell phone puts out about 1mw of power. A microwave puts out 10, 000 times more power than a cell phone. If a low power cell phone can transmit such a low amount of power in the microwave this does not sound good to me at all, as a microwave is pumping much more power and more than likely that much more RF leakage. Don't put your hands on or around the door of a microwave as you may receive an RF Burn....they burn from the inside out. I have an RF burn to my hip where I had it pressed up against the railing on a ship that I worked as an electronics technician. I was wearing rubber gloves to protect my bare hands; but did not give it a thought when trying to steady myself on a rocking ship working on an antenna coupler.....this was a long time ago and now procedure has one limiting exposure that I did not have at the time I was in the Navy about 40 years ago. A RF burn, burns deep, often not felt right away, and may not leave a burn mark on the skin. I was working in the vicinity of two 1000 watt transmitting antenna and a 35,000 watt radar system. A metal object that is not properly grounded can act as a re-radiator such as the railing on a ship. I question if the door on the leaking microwave has a good ground and I certainly would not put my hand on the door while it is in operation.

Amazing! I could tell where this was going from the beginning. Great info!

1. Cell phone distance to tower? No consistancy from location to location. Wifi was in the house where the cell tower may have been miles away or right near the house for different locations. 2. Cell phone antenna and receivers are more sensitive then ever. They can pick up insainly small signals. 3. Digital. Adds even more "sensitivity" to the phone system, allowing even weaker signals to be used. 4. The amount of leakage is small considering most ovens are 800 to 1000 watts. 5. Look into db attenuation and power. You will find an amazing fact about the effeciency of doubling your power, or how little of a difference 500 watts to 1000 watts make when compared to the difference between 0.5 watts and 1watt. "Weak" cell signals attenuated 30db are still very readable to a tower that is close. 6. 2.4 ghz and 2.45 ghz is 50 mhz apart..... take a look at how much and how different 50 mhz can make. I really like what you do and the channel you have, however 1st rule of science...know and/or control the variables. Lastly.... us crabby old guys have insane knowledge... feel free to ask sometime. May make reasearching easier.

Both cellular and wifi transmit on multiple frequencies... There are a wide number of standards (3G, LTE, etc) that your phone can try to connect to the local tower and then even within technologies like LTE there are multiple frequency bands. For instance AT&T 4G HSPA and HSPA+ use 850Mhz(Band 5) and 1900Mhz(Band 2) bands but it all depends on area if they own a license. LTE uses Band 17(700Mhz), Band 5(850Mhz), Band 2(1900Mhz), Band 4(1700/2100Mhz) currently. Similarly, your home wifi uses 2.4Ghz on the old standard but newer 5G devices transmit/receive on 5Ghz... so your friend's microwave could have been letting that through. The net is that the faraday cages used by microwaves have holes in them (so you can see the food) and those holes determine the frequencies that they block (wavelength needs to be smaller than those to get through). Enjoy your show and your enthusiasm.

I was taught that Faraday cages only block RF from getting into the cage and you can transmit outward. Of course, there will be attenuation transmitting out, but none of the cancellation. Therefore microwaves would be designed to attenuate microwaves from escaping at the frequency generated by the microwave, i.e., microwaves are not Faraday cages. In addition, while most newer microwaves are at 2.4 GHz, there are microwave ovens at different frequencies. Cellular phones transceive at different frequencies and not at WiFi frequencies. If I am wrong about the Faraday cage (and I may), please site references. The references I've seen, such as Wikipedia, Quora, etc. don't properly address the answer of transmissions escaping a Faraday cage (short of attenuation due to metal, not EMF cancellation).

Who heats up water in the microwave? I don't want all those deeeesgusting radio waves in my tea.

Really cool. Love the conclusions at the end of the experiment.

What an awesome video! I always wanted to visualize EMR and you delivered. Nice!

One thing I would as a matter of warning with microwaves, skin is not easily damaged by microwave radiation because it has blood running through it or very close. The one body part that can be very sensitive is the cornea, because it has a very low circulation rate of fluid. Frequent blinking reduces the risk, but heating clouds the cornea and is accumulative so don't put your eyes up against the microwave while cooking unnecessarily, and blink frequently when doing so.

Our business is in a metal building. Some cell phone carriers' phones do not work well at all inside the building, while at least one works fine in most locations inside. My speculation is either the frequency, or the proximity to that carrier's tower.

Very good video! i always knew this stuff. i climb cellular tower and install the cellular network and microwave dishes for towers. but finally somebody did a good video showing proof. which spectrum did you guys check? i saw 700. there is also 1900,850,2100 and 2600 usually for LTE. Thanks physics girl.

I know that there are resonant lengths for antennas at which they are most efficient. For example, a 1/4 wavelength antenna is more efficient than a slightly longer one, but a full wavelength antenna is even more efficient. Can Faraday cages have these same sort of "nodes" around which signals can pass through? I would expect that, even though a small amount of leakage occurred, the attenuation would be far too great for the 2.4 Ghz Wi-Fi signal to get through unless there was something else going on. The FCC maximum allowed transmit power for 2.4 Ghz Wi-Fi is 1 watt but it's not uncommon for microwaves to radiate 500-1,000 watts. You didn't give the power level detected, but it looked to be faint at whatever scale you were measuring.

I've made a test where I put one mobile phone to tether it's wifi connection (with the mobile network on) and used another phone to connect to this wifi (with mobile network off). While "pinging" both phones to each other, I put the "access point" phone inside the oven and closed the door. The ping success output then stopped for a few seconds and returned shortly after. After that I took out the "AP" phone back from the oven, put the other phone inside and then I could notice the same behaviour. Using an Wifi Analyser app I could see that the wifi was working on 2.4 GHz frequency and the only thing that has changed was the signal strength. With the oven's door closed it went down significantly but with enough strength to maintain the connection between the phones.

I loved the progression of this video, great job all!

Cool video, the only thing that's missing is turning the microwave on! :)

Physics Girl, you have been stepping up your game. Bravo!

Some of your videos are just so good and different from other science channels. Like the supernova (I love this one) or strange water vortex. This one was very also interesting. Thank you.

Heyyy its Samy. I followed your work for years. you're awesome dude.

I recently found out on my WiFi network (I use commercial equipment at home (I work in networking) so it can see things that you usually can't like rogue APs, what channels are they interfering, their signal power, etc) that my electric smart meter is producing five distinct WiFi signals that are very strong. And when I say strong, they are in the -50dBM range at over 50 feet from my own access point (AP) (the smart meter is outside my house completeley opposed to where my AP is), 3 walls, 1 celling and many metal conducts and home appliances in between. I never saw those signals before and all of a sudden they are there. I also see (at -80dBm though) the same kind signals from one of the nearby house smartmeter too. So I pushed my investigation further because I didn't find it normal that my AP could catch signals that strong at that distance. I did the microwaves oven test like you did and what I found is getting me worried. I transformed by iPhone into a WiFi scanner (you can do that by using AirPort utilility and activating the Wi-Fi Scanner option) by using the Air Port utility and let it scan continuously. With that, you can now find the strenght of any wifi AP (up to 5Ghz) - and that is how I found out that it was my smartmeter that was emiting those signals. I put my iPhone in the microwaves oven while the scanner was On and it could "see" all wifi networks in the area, including mine, the smartmeter, my neigbors, etc. But when I closed the door of the microwaves oven, it lost all wifi signals - and my own AP was barely 20 feet away but still lost its signal - except those 5 smartmeter signals that barely lost their strenght : from -50 dBm to -60 dBm. Now I know I am writting this in 2022 and there was a lot of complains back in the 2010-era about the safety of these smartmeters, but working in networking and knowing a bit about signal strenght for network optimization - and also what they can do the more you are near an AP - I can testify that these are not healthy level of radiations that are emitted from that smartmeter that far away. The room in my house that is adjacent to the wall where the smartmeter is installed outside receives signal strenght of -30 to -40dBm - that's the same as being 10 feet from your own AP at home in straight line with no obstable in between. I don't have my mG reader with me, but I will and measure those signal to see how "cooked" we are getting each day.