Hacker News Reader

Comment by flashdance | Hacker News Reader

> 5 GHz Wifi is technically SHF -- or Silly High Frequency

For those curious, op's right and it actually is SHF, but it stands for Super High Frequency. I don't understand humour, only RF (and even that, barely).

https://en.wikipedia.org/wiki/Super_high_frequency

Here's a fun semi-relevant science experiment you can do at home: running a microwave will kill nearby wifi and bluetooth connections. Isn't that strange?

Try it with a par of bluetooth headphones right now!

View on HN

> running a microwave will kill nearby wifi and bluetooth connections. Isn't that strange?

I replaced all of my light bulbs for bluetooth light bulbs.

Fun thing is that I can't turn on the light when the next door neighbors use their microwave. And by fun I mean dealbreaking.

I really don't know much about radio, but I have never experienced that the microwave have noticeably affected wifi or bluetooth.

Is it something that is only likely to happen with older and less isolated microwaves?

Most people aren't using wifi near running microwaves, so it's hard to notice. Some microwaves leak more than others, but none of them are required by the fcc not to interfere with 2.4ghz wifi. The FCC says that they can actually leak an unlimited amount of radiation at that frequency [1], although obviously if it's high enough to start cooking people standing nearby other agencies than that the will get involved.

I bet ya an upvote that yours still leaks enough. One thing to try is to put your phone next to the microwave and place your bluetooth headphones or speaker riight at the limit of its range. Turn on the microwave and see what happens!

[1] https://www.ecfr.gov/cgi-bin/text-idx?SID=c7be03a4f7b02514ce...

I once worked at a site that had the Wi-Fi access point for one side of the office in the break room. There was, of course, a microwave in the break room. There were frequently complaints around the lunch hour that the Wi-Fi didn't work well, though strangely it worked earlier and later in the day.

My parents have an open layout house with the kitchen directly behind the living room. Because of this, it was always common to get up, walk and make some popcorn while watching a movie.

Once they started using netflix, this habit had to be broken quick.

Yeah, modern microwaves shouldn't be leaking that much RF

Why wouldn't they leak RF? They aren't legally required to limit emissions at 2.4ghz.

> Why wouldn't they leak RF?

Customers might value using bluetooth and wifi. Not all pressures are regulatory!

Fair point.

is there any legal limit?

The FDA has one, but it's based on a maximum safe exposure to humans--which makes it fairly lenient.

I've found it varies a lot based on the microwave, distance (obviously) and positioning. My old apartment, anywhere in the kitchen and it'd kill my connection to my headphones. My new apartment (new appliances, too), I can be standing right in front of the microwave, and nothing.

Huh, my TV kept dropping the connection while streaming stuff from my computer downstairs. I wasn't using the microwave but maybe neighbors were... didn't consider this possibility. :D

Reply on news.ycombinator.com