WiFi was the killer technology that made home networking easy. No more messing around with hubs and cables and drilling holes in walls, simply turn the devices on and hit connect. Over time the speed and range has increased, but those with larger houses or granny flats out back have suffered. There are tricks to boost range however, and some of them involve cookware.
The clever hack here is to use a metal strainer as a parabolic reflector, to capture signals and focus them onto the PCB antenna in a USB WiFi dongle. The strainer is drilled out, and a USB extension cable has its female end glued into the base. This allows the dongle to be positioned inside the strainer. For best results, the dongle should be positioned so that its antenna elements are sitting at the focal point of the parabola; this can be determined through mathematics or simply by experimenting with positions to see what gives the best signal strength.
It’s a design that is quite directional, and should help boost signals as well as block out those from unwanted stations. The build is simple, and can even be tripod mounted which helps with aiming and looks cool to boot.
For many, WiFi antenna hacks are old school, but it’s always good to keep the techniques in mind as you never know when it will come in handy to solve a new problem. Some crazy things are possible with the right gear, too.
Huh, are we resurrecting decade-old articles?
WokFi goes back to at least 2008 – https://en.wikipedia.org/wiki/WokFi
Next great news will be Cantena!
No, Tetrapak horn antenna:
http://www.zoobab.com/tetrapakslottedwaveguideantenna
Every time I look at my steamer, I see an antenna. My kids get mad because I pretend I’m listening to a satellite. EVERY TIME.
ET did that in 1982. ;)
Yeah, it goes back earlier than that – I did it in 2006 in Moscow, and there were definitely folks doing this sort of thing before me.
http://www.fakeproject.com/Ikea_WiFi_Booster/
https://old.reddit.com/r/technology/comments/7q7t9/the_diy_ikea_wifi_booster/
Matthias Wandel (yeah, that guy again) has a pretty funny article about doing just this
That’s not a strainer, that’s a steamer.
(Well, you could use it as a strainer in a pinch, but it’s not very practical for that purpose. It folds open and is way to flat to be useful as a strainer)
I’m glad someone lointed tgat out. Lomg ago I moved from o e of thise folding steamers to one that is more like a pot with hokes tbat fits in nother lot.
I’ve never had a problem in 7 years with wifi, but I’ve always used adapters with antennas. I bought a usb wifi adapter a couple if years ago, and it came with a little stand and usb cable to position it better. If it plugged directly into a USB port, the comouter might act as a reflectir, but in a bad way.
Michael
Wow I haven’t seen a cook wear antenna for ages – I always loved those steamers – thought they would make a folding dish – never used one to steam something though.
That thing is about as far from being a parabola as it is possible to get…
its probably just acting as a flat reflector mostly.
I went a different route and used some ~40mm drain pipe to make a helical wifi antenna:
http://halestrom.net/darksleep/blog/032_helix_wifi/
I was able to get 2-3MBit from about 1.2km away of the AP. The AP was up a pole, using some form of standard whip (omni-ish) and completely obscured behind a building.
It ended up being the easiest of the options I tried. I’ve never succeeded at playing with parabolic cookware, probably because my cookware is the wrong shape and/or drilling a hole in the steel has been a bit beyond my equipment when in situations where I need remote wifi.
When it rained: my link died. Technically rain-fade shouldn’t kick in at 2.4GHz, but I came up with some other theories as to why it caused problems.
There’s also some interesting investigation into USB wifi cards on that page.
Good tips! I enjoyed the reading.
You’re a wizard, my friend…
How much is “works great” is in dBi?
and how many library of congresses can it transfer to the moon and back?
You can legally increase a receiver’s antenna’s gain.
Legally if you increase a transmitter’s antenna’s gain by X dB, you must reduce the transmitter power by X dB.
That ensures you do not increase interference in other devices.
47 C.F.R Section 15.247 (FCC rules)
(4) The conducted output power limit specified in paragraph (b) of this section is based on the use of antennas with directional gains that do not exceed 6 dBi. Except as shown in paragraph (c) of this section, if transmitting antennas of directional gain greater than 6 dBi are used, the conducted output power from the intentional radiator shall be reduced below the stated values in paragraphs (b)(1), (b)(2), and (b)(3) of this section, as appropriate, by the amount in dB that the directional gain of the antenna exceeds 6 dBi.
(c) Operation with directional antenna gains greater than 6 dBi.
(1) Fixed point-to-point operation:
(i) Systems operating in the 2400-2483.5 MHz band that are used exclusively for fixed, point-to-point operations may employ transmitting antennas with directional gain greater than 6 dBi provided the maximum conducted output power of the intentional radiator is reduced by 1 dB for every 3 dB that the directional gain of the antenna exceeds 6 dBi.
(ii) Systems operating in the 5725-5850 MHz band that are used exclusively for fixed, point-to-point operations may employ transmitting antennas with directional gain greater than 6 dBi without any corresponding reduction in transmitter conducted output power.
(My comments): in any case the RF transmit power into the antenna isn’t permitted to exceed the limits specified for the band. BTW: 6 dbi isn’t much. Most WiFi boxes operate at a small fraction of the authorized power. There is a lot to be gained by using a high end WiFi box such as a Mikrotik, Cisco, Meraki, etc. You can generally gain as much as 8 dB by using a big honking radio box which operates at the legal limits.
To find the best focal zone for a steamer you’d need to stand something white up in the center, then mount a laser pointer aimed straight down. Move the steamer petals until moving the laser radially in and out produces the least vertical motion of the reflected laser light on the white thing. Should wear protective glasses while doing this to protect against wild reflections.
If you want to get real creative with a steamer, figure out a way to adjust the curvature of the petals and press the flat bottom into a bowl shape to tighten up the focus. If the reflection from curving the bottom can be at least loosely focused out beyond where the USB dongle’s antenna is (they seem to be near the end opposite the USB plug), a small, curved reflector mounted there could bounce some energy back at the antenna.
Easy way is plot a parabola of the right size and focus and cut it out. Use as a template to set the petals to a best fit.
Been there done the cookware thing, it works but not as well as the old school round direct TV dish I picked up and made into a wifi xmtr,/rcvr using a ddwrt flashed router in bridge or AP mode.. I was connected to and using a uhaul company’s guest Network thats roughly 1/2 a mile from my house with direct line of sight from the 2nd story..
Well, of course not. The directv dish is built for that very purpose. :)
I did the same with an old Netgear USB wnic mounted at the focus of an old dish. Connected to the guest network at the McDonalds at truck stop 1 mile down the road.
Running everything through a VPN because…security.
Yeah? Well I did it with an old galvanized sheep-dip trough and the WiFi at a Starbucks in town 7 miles away. And it was uphill both ways!
A quick and easy way to find a workable focal point for short wavelength signals is to use a flashlight or car headlight. Focus a flashlight at the steamer from a long distance, hold a dowel along the central axis of the reflector, then adjust the flaps until you find the combination that reflects the most light onto a single point or ring around the dowel. Lock the flaps in place, then mark the dowel at the focal ring. Initially mount the USB stick or receiving antenna element using the marked dowel as a gauge, then fine tune the position along the axis by testing reception using your intended frequency.
This also works with using a wok stirrer, old satellite dish, or any roughly parabolic shape as an antenna reflector, but it helps to first line the surface with shiny aluminum foil in order to easily see the focal point.
Take a string of sufficient length many times the dish diameter. Tie one end of the string to the radiating element location. Hold the other end of the string against a flat plane( (perhaps a wall) where the string can be “folded ” behind the radiator. As long as the string is exactly perpendicular to the wall, the folded part of the string defines a perfect parabola in all of the different locations where it can be folded in a taught fold with the string perpendicular to the wall. It is how C band dishes were measured for focal length back on the early days. All it takes is a not stretchy string. It also teaches how parabolic reflectors work, in that the RF waves take a reflective path off a reflector, bounce and then arrive at a location in front of the dish where all of the waves are delayed by the exact same amount of time (the length of the string) to combine in a plane wave.
When I was 11, in 1962, I used my aluminum saucer shaped snow sled to build a parabolic microphone. Faced it towards the sun to find the focal point, (ouch), used a piece of a bamboo fishing rod screwed to the center to hold a cassette recorder microphone at the focal point. Worked pretty well. It was about 30 inches across.
Fast forward to about 2013, used a discarded Dish Network dish and hot glued an old wireless usb G dongle where the LNA were. That worked incredibly well. I piked up dozens of new signals every 5 or 6 degrees of swing. Very few open routers though. Remember wardriving.
Oddly enough neighbor’s house has an old DirectTV antenna still there. Now powering all that through existing wires would be interesting.
Are you my missing twin? Though in ’62 it was a Christmas gift little battery powered reel-to-reel. I don’t recall any cassettes at that time. I also made a “fish-listener” based on some article about using a pair of copper plates about a yard apart to (supposedly) hear sound due to changes in conductivity. Never picked up a thing and found a few years later it was a purely speculative paper.
If your going to use that sucker outside you’ed better put it in a plastic bag.
Thanks thorium\n
I try to make my articles cover stuff that I don’t read elsewhere. Finding different antenna designs is mostly chance, I wish there was a big table of antenna designs on the web with columns like “Balanced Y/N” and “Polarisation”.
It was fun to do and I still occasionally dream about rooftop-to-rooftop helical wifi mesh networks.
(My last comment (hopefully this parent) should have posted as a reply to thoriumbr. Perhaps having JS disabled broke it? )
Here’s to the old women who calmly knitted out of gold wire a mesh for those folding dishes that rode along with the moon explorers. Sounds like a future article?
Wait, that had a supporting mesh? I always thought it was like an umbrella, a rigid metal construction with something like aluminised mylar stretched in between…
This calls for a USB Wifi dongle and usage of USB extension cables. What is the best way to get a signal to my router, as the USB dongle connects direct to my Laptop?
An extension cable for the Wifi Antenna? 1m cable won’t do. 3m in a pinch. 5m ideally. But then there are cable losses to deal with that may not make it worth the while.
A really small weatherproofed router placed at the focal point ( or a 1m antenna extension cable) and supplying power to the router outdoors? Maybe a ESP8266/32 with a battery topped up by solar power?
There are plenty of programs that allow you to analyze the signals with a laptop. Not all routers have the features that can analyze signal strengths, esp over time when you sweep the antenna. Maybe sweep an antenna connected to the USB dongle, and then when the ideal spot is located connect the antenna to the router?
Maybe the ESP device in AP mode should be my start, at least I can hook up the antenna outside with a short run to a weatherproofed box, and I can control the software side as well to get the best signals of the various AP’s over time?
Replying to myself, the link from Hales’ post above http://halestrom.net/darksleep/blog/032_helix_wifi/ may be all I need. Thanks!
what is wifi ?
currently picking up wifi over 30m from connection, no idea how it reaches this far.
Keep in mind with decent antennas, legal limit power, sufficient antenna height with 0.6 first Fresnel clearance 4/3 and 2/3 earth curvature, etc., 15 mile high reliability wifi band paths are routine between oil rigs in the gulf of Mexico. In rural WISPs large mesh arrays of multi mile hops are the “bread and butter” of the business. I remember taking apart a 13 dBi gain general Dynamics panel antenna which was basically a dipole properly spaced in front of a cake pan . There is a whole lot more to wifi than most people see and a lot of room for experimentation.
When I moved to my current house and was without internet for 2 weeks, a wok lid and a laptop with a shared internet connection served as my less than high speed but functional internet connection. https://photos.app.goo.gl/6pHiG53ervsp44987
While it may not be as efficient, three sheets of metal meeting at right angles is a ‘good enough’ reflector for most uses.
They’re not just good enough, they’re better than parabolas in other ways. A 90 degree corner reflector can be scaled up in size easily and you won’t run into the focal point issue a dish would have.
It’s way easier to DIY too. Get a metal sheet, cut/bend it and you’re basically done. Much easier than trying to make a dish that reflects just right.