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Ask HN: Does your microwave interfere with Bluetooth? Mine does

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Re: Ask HN: Does your microwave interfere with Bluetooth? Mine does

#81

My neighbors have something crazy emanating from their house. None of my Bluetooth devices, from Bose to Plantronic to new AirPods Pro, survive signal connectivity when I walk past their house. The connection gets very disrupted and the devices have trouble reconnecting. So I have to leave everything off when I go for a run and not connect headphones until I make it to the end of the street. It’s weird.

The same can also be very localized. On my way to work there is a 2x2m spot in the middle of open space that does that too

Re: Ask HN: Does your microwave interfere with Bluetooth? Mine does

#82

There's about 1000 watts of RF inside the microwave, it has to be attenuated to less than a few microwatts on the outside to avoid congestion, as they use the same frequency band. I'm amazed WiFi or Bluetooth ever works at all. 8) You can thank Hedy Lamar for that. Try cleaning the mating surfaces around the door thoroughly. If that doesn't work, consider replacing the microwave or relocating the speaker.

Wifi has an "interference robustness" option which is designed with microwave ovens in mind. The power output of a microwave is a sine wave, because it's powered from your AC line power, and doesn't emit energy during the zero crossings. "Interference robustness" times packet sends (and lengths) to be when the microwave is producing the least amount of power. Thus, you spend half of every 60th of a second irradiating…

I have an inverter microwave. Before I went crazy with APs around my house, that microwave would win the war; no zero-crossings to sneak a packet by it.

Now my bluetooth only drops when I'm fairly close to the microwave as it runs. (EDIT: my WiFi, not my Bluetooth)

Re: Ask HN: Does your microwave interfere with Bluetooth? Mine does

#84

You can demonstrate WiFi interference by putting a laptop next to your microwave and running a ping test to your WiFi router. I can put my laptop about 4 feet away from my microwave and the ping test hangs as soon as the microwave starts. The ping test resumes as soon as the microwave stops.

I haven’t had my afternoon coffee yet, and I read this as though the ping test stops when you put your laptop in the microwave and turn it on.

Re: Ask HN: Does your microwave interfere with Bluetooth? Mine does

#86
Tangentially related: knowing they use the same frequency band, I actually used the work microwave oven as a faraday cage for testing our product which used bluetooth. (Close door, observe signal drop behavior). I was bemused to note that you could still connect to a device inside the oven, over short distances... Hopefully the attenuation was sufficient for safety when using it to cook!

[ For clarity - the oven wasn't on when I used it as a faraday cage]

Re: Ask HN: Does your microwave interfere with Bluetooth? Mine does

#87
post #70

Earlier quoted context omitted.

I use my microwave constantly, but it's all for defrosting. Once the food is no longer frozen but not yet piping hot, it then goes into the toaster oven or skillet or whatever to finish heating including crisping/browning. It's great because it not only saves significant time, but loses less moisture. Heating from frozen in an oven dries things out too much, or you have to use up aluminum foil to wrap it, which is an…

We eat soup once a week, on Saturday usually. I open the package (like this [1]), put it in a pan. Warm it up and... have soup. With a fresh baguette, some hummus or aioli or whatever. No microwave required. If its frozen soup (made in bulk it is very cheap) then it just has to be put out early enough. A microwave could help to defeat bad planning or tough time schedule. [1] https://www.ah.nl/producten/product/wi920/…

Well sure. Like I said, the main benefit of the microwave is to defrost faster. Nothing requires a microwave.

And soup doesn't benefit from browning or crispness so you can heat it up in the microwave the whole way.

There's nothing wrong with the pan, it just takes longer. And there isn't any taste/texture benefit over the microwave in the case of soup.

Re: Ask HN: Does your microwave interfere with Bluetooth? Mine does

#89
Nope, this is completely normal.

Many commenters are saying microwaves are pretty narrowband.

Maybe some are, but I've done spectrum analysis on a few college-dorm-level microwaves in our office with a Wi-Spy and all 3 of these microwaves spam all of the 3 usable 2.4ghz wi-fi channels when cooking.

We see similar fun in iMac labs, when they're all (attempting to) use Bluetooth Apple Magic Keyboards at once.

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