4 ms·

Can this be used to detect radiation escaping a microwave oven? A friend of mine has a microwave that noticeably degrades his wifi when it is in use.

zxexz 10mo ago
Sounds like he’s in need of a new microwave. Not tongue-in-cheek; sounds like there’s something up with the shielding, and if it’s not visible, how will you know if it gets worse? Edit: I see no reason this wouldn’t work, however?
- jeffbee 10mo ago
  There is not substantial variance from one microwave to the next. They are all made by one outfit, then dressed up in different superficial brands and priced randomly. The emissions of a microwave oven are regulated by the FDA, not the FCC.
  - macintux 10mo ago
    That doesn't mean, however, that an aging appliance can't misbehave.
bgbntty2 10mo ago
I've tested a few microwaves from different manufacturers with my phone a few years ago. I think I looked at some file in my router (OpenWRT), but I can't recall. I got a lot of dropped packets each time. The amount of degradation was similar for the different microwaves. I had to put the phone close to the microwave to detect this. The degradation was obviously stronger when the phone was closer. If your friend experiences noticeable degradation regardless of the distance within the room, it might be worrisome. But I think it's normal to have some interference. That doesn't necessarily mean enough of the 2.4 GHz radiation escapes the microwave to be harmful to an animal, as Wi-Fi, Bluetooth and so on are very weak, comparatively. Funny thing is, after putting my phone inside a closed turned off microwave, it got Wi-Fi, although very weak. I didn't try that with all the microwaves, but with 2 or 3 of them. I think the Faraday cage around the microwave was built to be good enough for safety, but it wasn't built with Wi-Fi interference in mind. Disclaimer: I might be wrong, as I don't have enough background to make any bold claims.
- avidiax 10mo ago
  > If your friend experiences noticeable degradation regardless of the distance within the room, it might be worrisome. Probably not. I recall calculating it once, and the legal requirements for microwave oven shielding still allow it to produce a few watts of 2.4Ghz leakage. This is contrasted to 50mW typical WiFi AP power, and 5-50mW BlueTooth powers. A few watts is totally non-dangerous to humans, especially diffused across the entire door.
  - shibapuppie 10mo ago
    An old Unifi disc AP will do 100mw or 20dbm out of the box, a few cheap Cudy APs I have do about 400mw or about 26dbm. On 2.4 GHz in the US you're allowed up to 36dbm, 30 of that can be transmitter, the remaining 6 can be a higher gain antenna.
bcook 10mo ago
For devices where connectivity is more important, switch them from 2.4Ghz to 5Ghz to avoid microwave interference.
- nja 10mo ago
  Other than phones and laptops (i.e. "real computers"), most devices only support 2.4, no? I can't recall the last time I set up a non-computer device that didn't say "make sure you're using a 2.4GHz network"... (I imagine it's a much lower cost to only handle 2.4GHz?)
  - tzs 10mo ago
    I was curious so checked my network. I've got 21 things on 2.4 and 16 things on 5. The 16 are 4 computers (2 Macs, a Surface Pro 4, and an RPi 4), 3 mobile devices (iPhone, iPad, Apple Watch), 3 media devices (Fire TV, Nintendo Switch, and Kindle Oasis), one smart plug, a Brother printer, 3 smart speakers (Google Home Mini, two Echos), and an EV charger.
tgv 10mo ago
The article says: "responds to [...] microwave oven leakage".
KaiserPro 10mo ago
You could subsitute the LED for a moving coil meter: https://www.codrey.com/electrical/moving-coil-meter/ https://www.codrey.com/electrical/moving-coil-meter/ They have am much lower current and voltage requirement, so might me more sensitive. You can also do tuning to use different sized antenna. However that strays into analogue eletronics, which I've not really touched for 15 years.
jeffbee 10mo ago
Microwaves degrade everyone's 2.4 GHz ISM band radios. Wi-Fi occupies the ISM band because it's a garbage band that was already wrecked by this type of equipment. There isn't a solution to this; the safe leakage from a microwave oven is millions of times more powerful than wifi field strength. 5 or 6GHz band avoids the problem.
- georgefrowny 10mo ago
  There is a solution. Spread-spectrum methods for digging out signals from deep in the noise floor. It's just maths, but the amount of noise you can reject that way is really nuts.
pwg 10mo ago
From the fine article, second paragraph: "you can build a tiny “crystal detector” that responds to 2.4 GHz Wi-Fi, Bluetooth, and even microwave oven leakage"
pseudohadamard 10mo ago
If they're seriously concerned, you can get microwave leak detectors for very little money from most crapvendors. The problem with this design is that while it's a cool toy it'll be prone to false negatives...

zxexz 10mo ago

Sounds like he’s in need of a new microwave. Not tongue-in-cheek; sounds like there’s something up with the shielding, and if it’s not visible, how will you know if it gets worse? Edit: I see no reason this wouldn’t work, however?

jeffbee 10mo ago
There is not substantial variance from one microwave to the next. They are all made by one outfit, then dressed up in different superficial brands and priced randomly. The emissions of a microwave oven are regulated by the FDA, not the FCC.
- macintux 10mo ago
  That doesn't mean, however, that an aging appliance can't misbehave.

bgbntty2 10mo ago

I've tested a few microwaves from different manufacturers with my phone a few years ago. I think I looked at some file in my router (OpenWRT), but I can't recall. I got a lot of dropped packets each time. The amount of degradation was similar for the different microwaves. I had to put the phone close to the microwave to detect this. The degradation was obviously stronger when the phone was closer. If your friend experiences noticeable degradation regardless of the distance within the room, it might be worrisome. But I think it's normal to have some interference. That doesn't necessarily mean enough of the 2.4 GHz radiation escapes the microwave to be harmful to an animal, as Wi-Fi, Bluetooth and so on are very weak, comparatively. Funny thing is, after putting my phone inside a closed turned off microwave, it got Wi-Fi, although very weak. I didn't try that with all the microwaves, but with 2 or 3 of them. I think the Faraday cage around the microwave was built to be good enough for safety, but it wasn't built with Wi-Fi interference in mind. Disclaimer: I might be wrong, as I don't have enough background to make any bold claims.

avidiax 10mo ago
> If your friend experiences noticeable degradation regardless of the distance within the room, it might be worrisome. Probably not. I recall calculating it once, and the legal requirements for microwave oven shielding still allow it to produce a few watts of 2.4Ghz leakage. This is contrasted to 50mW typical WiFi AP power, and 5-50mW BlueTooth powers. A few watts is totally non-dangerous to humans, especially diffused across the entire door.
- shibapuppie 10mo ago
  An old Unifi disc AP will do 100mw or 20dbm out of the box, a few cheap Cudy APs I have do about 400mw or about 26dbm. On 2.4 GHz in the US you're allowed up to 36dbm, 30 of that can be transmitter, the remaining 6 can be a higher gain antenna.

bcook 10mo ago

For devices where connectivity is more important, switch them from 2.4Ghz to 5Ghz to avoid microwave interference.

nja 10mo ago
Other than phones and laptops (i.e. "real computers"), most devices only support 2.4, no? I can't recall the last time I set up a non-computer device that didn't say "make sure you're using a 2.4GHz network"... (I imagine it's a much lower cost to only handle 2.4GHz?)
- tzs 10mo ago
  I was curious so checked my network. I've got 21 things on 2.4 and 16 things on 5. The 16 are 4 computers (2 Macs, a Surface Pro 4, and an RPi 4), 3 mobile devices (iPhone, iPad, Apple Watch), 3 media devices (Fire TV, Nintendo Switch, and Kindle Oasis), one smart plug, a Brother printer, 3 smart speakers (Google Home Mini, two Echos), and an EV charger.

tgv 10mo ago

The article says: "responds to [...] microwave oven leakage".

KaiserPro 10mo ago

You could subsitute the LED for a moving coil meter: https://www.codrey.com/electrical/moving-coil-meter/ https://www.codrey.com/electrical/moving-coil-meter/ They have am much lower current and voltage requirement, so might me more sensitive. You can also do tuning to use different sized antenna. However that strays into analogue eletronics, which I've not really touched for 15 years.

jeffbee 10mo ago

Microwaves degrade everyone's 2.4 GHz ISM band radios. Wi-Fi occupies the ISM band because it's a garbage band that was already wrecked by this type of equipment. There isn't a solution to this; the safe leakage from a microwave oven is millions of times more powerful than wifi field strength. 5 or 6GHz band avoids the problem.

georgefrowny 10mo ago
There is a solution. Spread-spectrum methods for digging out signals from deep in the noise floor. It's just maths, but the amount of noise you can reject that way is really nuts.

pwg 10mo ago

From the fine article, second paragraph: "you can build a tiny “crystal detector” that responds to 2.4 GHz Wi-Fi, Bluetooth, and even microwave oven leakage"

pseudohadamard 10mo ago

If they're seriously concerned, you can get microwave leak detectors for very little money from most crapvendors. The problem with this design is that while it's a cool toy it'll be prone to false negatives...