this post was submitted on 29 Nov 2024
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CAFE by GE for those who are wondering.

We are renovating our house including all new appliances. I have told my partner to make sure we get non smart appliances. This is why.

Yes I can setup a VLAN for it to be on but that's not the point.

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[–] [email protected] 1 points 3 weeks ago* (last edited 3 weeks ago) (1 children)

The water resonance thing is a myth, AFAIK. Strong absorption is actually a bad thing for a microwave oven, because then it would only heat the surface. The way they work is effectively bouncing the radiation through a barely-absorbing dielectric thousands of times, to get the effect really even.

The frequency is probably just an easy one to build magnetrons for.

[–] [email protected] 1 points 3 weeks ago (1 children)

The frequency is probably just an easy one to build magnetrons for.

The real reason is that that range is reserved for consumer devices so that it doesn't interfere with actual ISM sanctioned communications as enforced by the FCC. We just also decided to put wifi in the same range cause they're stingy releasing frequencies for public use.

https://en.wikipedia.org/wiki/ISM_radio_band#Frequency_allocations


But research was done on it cause of course it has been.

https://iopscience.iop.org/article/10.1088/0031-9120/39/1/006

This article deals with the generation of microwaves in the oven and includes the operation of the magnetrons, waveguides and standing waves in resonant cavities. It then considers the absorption of microwaves by foods, discussing the dielectric relaxation of water, penetration depths of electromagnetic waves in matter and, in considering the possible chemical changes during the microwave heating, multi-photon ionization or dissociation.

So you're likely right that it's not water resonance, but chassis cavity resonance. I can't say that I've read deeply into it. And thinking about it I remember hearing something about some of the high level stuff that I just read in relation to this article. I probably ran into it in passing and just failed to recall it. But to be frank, I'm okay just calling it voodoo wizardry in of itself. But I have to understand wireless communications stuff for my profession, and it's well known that it's basically the same range as wifi 2.4ghz/bluetooth/other consumer standards that sit in the same crowded space.

[–] [email protected] 1 points 3 weeks ago* (last edited 3 weeks ago)

There's several ISM bands, though, pretty evenly spaced. The 13.5MHz one is used for passive RF chips like on credit cards, for example. They're skinny, but for purposes where bandwidth doesn't matter they can be. For other purposes bandwidth is scarce enough there has to be tight regulation.

Actually high water absorption happens in mm wave bands up in the hundreds of GHz (and THz too, if we could make a decent transmitter). Those fucked up riot control devices that make your skin feel on fire work based on that principle, because the heat will only go deep enough to hit pain receptors. Presumably, they stop working if you get a water mixture of any kind on the window, too.