5 GHz WiFi has a wavelength around 6cm so it can’t “see” anything smaller than approximately that. The things you want to see in your walls are below the diffraction limit for WiFi.
Ask HN: Any tools to do generic WiFi imaging?
21–30 of 71 posts
Re: Ask HN: Any tools to do generic WiFi imaging?
#22Did you look into stud finders? They’re devices specifically made to detect pipes and electrical wiring in walls. I love that you immediately went to WiFi for this though. Gotta love us tech people over complicating things haha!
Cheap stud finders are usually not great. The good ones are radar-based using similar frequency bands to wifi, but they cost lots of $$
Re: Ask HN: Any tools to do generic WiFi imaging?
#232.4ghz isn't great at detecting small obstacles like wires. There's a smartphone mounted device that can do this with 60ghz: https://walabot.com/
Re: Ask HN: Any tools to do generic WiFi imaging?
#24There's a youtube channel called "Thought Emporium" which earned my sub many years ago with this video series on building a wifi camera.
Part 1: https://www.youtube.com/watch?v=o6WHhqDHSQ4 Part 2: https://www.youtube.com/watch?v=VABeN4uv03s
Re: Ask HN: Any tools to do generic WiFi imaging?
#25Get an infrared thermometer camera. I have a FLIR add-on for iPhone that lets me see studs, gaps in insulation, leaks... it's amazing what shows up.
It won't show cables, unless they're hot. You can use an AC stud finder for that.
You can flip the photo between the actual and IR image, and it overlays an outline over the image.
I make a video in and out of the house on the hottest and coldest days.
Re: Ask HN: Any tools to do generic WiFi imaging?
#26Earlier quoted context omitted.
It takes 2 minutes to fix a hole with filler paste. You can also find a discrete place to put it, like the opposite side of the wall, under the threshold, behind a closet, using existing holes for wiring. Drilling gently through wood or gypsum, you will notice immediately that you got through the sheet, before you can even hit a pipe or anything else behind. Then use that hole for the endoscopy to map out the beams a…
As i have not done this, my concern was drilling into wiring. I have a multi story house and i figured there could be writing that drops down through the walls that are not directly aligned with any switch. Am i being overly paranoid ?
It’s good to be cautious. Drill slowly, with the assumption that you are going to hit something.
If you assume that your walls are 12mm gypsum and you stop drilling after 12mm, nothing can happen, start slowly, use the smallest drill, tape your drill as stop reference. If you hit open air you will immediately notice that you’re through. If you don’t hit open air after 12mm, stop, think, reconsider. Maybe you have thicker walls, maybe you hit a beam, etc.
The difference between gypsum, wood and steel is so big you will feel the difference if you go slowly. With gypsum you can almost push a needle through with hand force, from there make the hole bigger. Concrete walls are a totally different story.
Don’t have the intuition for how it feels once you get out on the other end of a plank yet? Dry run using a scrap piece of wood, where you can see the back side. Pin some scrap wire on the back and see what happens when the drill hits a worst case scenario. In a real wall the wire would be assembled before the final panel so there you’d have even more spacing. Logically, the wire will be behind the sheet, not embedded inside it.
Re: Ask HN: Any tools to do generic WiFi imaging?
#27Did you look into stud finders? They’re devices specifically made to detect pipes and electrical wiring in walls. I love that you immediately went to WiFi for this though. Gotta love us tech people over complicating things haha!
Cheap stud finders are usually not great. The good ones are radar-based using similar frequency bands to wifi, but they cost lots of $$
You beat me to it. I'd say "usually not great" is putting it too lightly.
They're awful and if you don't realize they're awful then you might make regretful decisions based on their slanderous output.
Re: Ask HN: Any tools to do generic WiFi imaging?
#28Get an infrared thermometer camera. I have a FLIR add-on for iPhone that lets me see studs, gaps in insulation, leaks... it's amazing what shows up. It won't show cables, unless they're hot. You can use an AC stud finder for that. You can flip the photo between the actual and IR image, and it overlays an outline over the image. I make a video in and out of the house on the hottest and coldest days.
What have been your top discoveries with the FLIR device?
Re: Ask HN: Any tools to do generic WiFi imaging?
#29Did you look into stud finders? They’re devices specifically made to detect pipes and electrical wiring in walls. I love that you immediately went to WiFi for this though. Gotta love us tech people over complicating things haha!
Stud finders are for finding studs, not pipes and wiring.
Re: Ask HN: Any tools to do generic WiFi imaging?
#302.4ghz isn't great at detecting small obstacles like wires. There's a smartphone mounted device that can do this with 60ghz: https://walabot.com/
Have you tried this product? What do you think of it?