Defeat Blood-Sucking Mosquitoes By Becoming The Bug Zapper

One of the stun gun modules with battery pack. (Credit: Dani Cruster DiWHY, YouTube)
One of the stun gun modules with battery pack. (Credit: Dani Cruster DiWHY, YouTube)

Few things are more satisfying during a Summer night than hearing the crackle and pop of another mosquito hurling itself against a bug zapper and knowing that it won’t be trying to suck your blood any more. The only problem with those bug zappers, whether the mounted or hand-held type is that you cannot get every single attacking mosquito. Unless you were to put the bug zapper on yourself, of course. This is basically what [Dani Cruster] of the aptly named ‘DiWHY’ channel decided would be the right course of action.

The video is apparently dubbed over from the original Russian – with the team claimed to be based in Moldova – which probably explains a lot of the reasoning behind this engineering. At the core of the whole-body bug zapper is galvanized mesh, with a big question being how close you can get it to the body before said body gets zapped too. With about a millimeter of clearance between both layers of mesh required at 1 kV, this was another design consideration.

Ultimately the guts of stun guns were used, which output around 10 kV and thus require a 1 cm gap between the mesh layers. PVC plates were used to create the structural elements of the walking bug zapper suit, using a heatgun to form it into a body-appropriate shape. That’s when human testing started, to try and not make it zap the wearer.

The final suit of bug zapping armor uses six stun gun modules, each powered by a 3 V power source created from two 1.5 V alkaline cells that are good for an hour of zapping. One issue found during a human trial run was that the zip ties used turned out to actually cause arcing, which had to be addressed first before heading to the mosquito-infested woods. In the video these are said to be near Tarkov in what appears to be the national park in Russia’s Tver Oblast and clearly a prime mosquito breeding ground.

During the real-life test run many mosquitoes and apparently even some ticks find their electrifying demise, before for some reason they seem to clear out after an hour or so. Overall it seems to work well, even if it’s not that ergonomic and things get spicy when it starts to rain.

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A drone is shown flying above some trees and a building. A pink cloud of dots appears above the drone, and a purple cloud below the drone. Grey crosshairs are to the right of the drone.

Seeing The World In Radio Waves With The QuadRF

Although the basic principle of radio direction finding is easy to understand (measure the phase difference between different antennas, then calculate the angle of arrival from this difference), the radio hardware to actually implement this has historically been hard for hackers to access. The QuadRF project aims to change this by building a phase-coherent four-channel SDR which makes direction mapping easy (GitHub repository).

The QuadRF uses two boards: one to receive and pre-process radio waves, and a Raspberry Pi 5 for additional processing. The RF board has four patch antennas, each capable of either transmitting or receiving in the 4.9 GHz to 6.0 GHz range, with switchable right- or left-hand polarization. For on-device processing, it uses a Lattice ECP5 FPGA, which uses two MIPI cables to connect to the camera and display interfaces on the Raspberry Pi. These form a very high-speed data exchange, and after further processing, the Pi can pass data on over Ethernet or Wi-Fi. Individual QuadRF boards can connect together in a lattice grid to form larger phased arrays.

The QuadRF’s software shows off its real strength: it’s compatible with standard programs like GNU Radio, but it also hosts a few of its own programs. The most striking of these is an “RF camera” which scans its entire frequency range at 30 fps, tracking the direction of detected signals and visualizing them on a spatial plot. When overlaid on a camera feed, this plot lets one easily see the radio signals emitted from electronics; as an example, the creators tracked a drone in flight, even distinguishing the two radio transmitters on the drone.

This isn’t the first multi-antenna SDR we’ve seen, though this is the first that could transmit. It’s important to be careful, though: some applications of this kind of hardware run afoul of arms regulations.

Thanks to [Swake] for the tip!

Tricking A Bike Counter

Some municipalities implement bike counters on cycling routes in order to monitor traffic. [nullpxl] recently investigated how these counters work, and explored methods that can be used to trick the counter into thinking a bike passed over it.

A great many of these devices are built using inductive loop sensors. This involves passing a current through a loop of wire embedded in the ground. When a conductive item such as the metal wheel of a bike passes through the electric field, eddy currents are generated in the item, creating their own magnetic field which reacts with the loop’s field itself. This creates a change in inductance which can be measured, and thus used to log the number of times a conductive item has passed over the sensor. By looking at the signature of the inductance change, a system can be tuned to detect specific objects—for example, two bicycle wheels passing over a sensor will create a signal that varies over time in a characteristic way.

[nullpxl] first tried to recreate a “bike” signal for the inductive loop by running over the area holding two metal pans. This wasn’t close enough, so a new idea was needed. Experiments with a scrap bike then indicated that there was a speed gate involved, and that wheeling one wheel over the sensor and back again could trick the sensor into thinking a bike had passed by. Eventually, [nullpxl] distilled all this learning down to create “the BIKE BASKET.” It’s simply a bag with a bike wheel in it, and swinging it over the sensor twice makes the counter tick up.

Is there any money in tricking the average municipal bike counter in your local city? We doubt it, unless Big Bike is getting increasingly filthy in its lobbying efforts. In any case, we love to see weird sensor hacks around these parts. Continue reading “Tricking A Bike Counter”

Home Automation: Simple Vs Easy

We’ve been talking a bunch of home automation on the Podcast lately, and this week, in the Mailbag segment, a reader asked us about our setups. Neither Kristina nor I are poster children for the home automation movement: she has absolutely no smart anything because she didn’t want her data up in “the cloud”, and I have an entirely local system that’s really nothing more than a bunch of ad-hoc scripts that talk to an MQTT broker, everything fully DIY but held together with metaphorical duct tape. Neither of us are doing it right, but we’re doing it wrong in interestingly different ways.

Kristina thought, probably because of the range of commercial devices out there that tie you into using their remote data storage services, that giving up control of her data was necessary to use it. And it might be, if you insist that setting up the system be as easy as possible. But the tradeoff for this ease is a drastic reduction in simplicity. You shouldn’t need a remote server in some foreign country to turn your lights on and off. Adding “the cloud” into the mix brings a lot of complexity, mostly in the form of servers that have to be paid for somehow by whatever company is providing the service. It needs to be secure. You might even have to create accounts, remember passwords, and manage that whole deal. Sure, that’s easy enough, but it’s a lot of moving parts, and you can’t blame her for rejecting that complexity.

My system is hosted on a now-ancient OrangePi in the corner, and the network in question is an old WiFi router that it sits on. Nothing needs to leave my four walls, but actually some of it does – I bridge some of the MQTT topics out to an external server for my own amusement. There is no protocol, and no real “system” frankly. Each device in the network has its own topic, and I’m responsible for knowing what it means. The thermometer in the basement has an ESP8266 that transmits on the home/basement/temperature topic, and it puts out its temperature in degrees Celsius. It was the simplest system I could think of, but I have to write whatever software I want to log, display, or act on the data. Of course, that’s simple if you can write some four-liner scripts on the OrangePi broker, but it’s not easy enough that my wife wants to hack on it.

So if the full-buy-in commercial systems are easy but overly complex, and my DIY network is transparently simple but requires a level of hands-on that isn’t easy for “normies”, is there a middle ground? I know half of you are already screaming Home Assistant or Domoticz, and you’re also thinking of which client device libraries you like the most for all your DIY applications: ESPHome vs Tasmota, for instance. And you’re all right!

We are living the in the golden age of the home automation projects. Open-source software and firmware, combined with an abundance of online tutorials and worked examples, have made huge strides toward bridging the gap between simplicity and ease of use. You can set up a hub for everything on a single-board computer, upload the software of your choice, and you don’t need the complexity or loss-of-support liability of a cloud provider. At the same time, setup is easy enough if you’re willing to roll up your sleeves a little bit, and when it’s not, chances are good that someone else has already figured it out for you. These days, interoperability with popular commercial products is shockingly easy to boot.

I need to spend some time and rationalize my system: given the state of the art, it’s simply too simple, and taking a step into an open-source solution would make it easier to use for the rest of the family, without overly complexifying things, adding sketchy dependencies, or losing our data sovereignty. I haven’t finished exploring my options yet, but from what I can see, the community has converged on some goldilocks setups: not too simple or too easy, but rather just right. Thanks, y’all!

The Repair Nightmare That Are Smart Rings

In the quest to make every wearable device ‘smart’, a lot of electronics along have to be crammed in very small spaces, along with ways to make them resistant to environments that our bodies do not mind, like getting hit by a rainstorm or simply washing our hands. These two factors combined make especially devices like smart rings an interesting case study for repairability, with [iFixit] recently taking apart a modern Oura smart ring to assess its e-waste factor after the built-in battery dies.

The tiny 10.5 mAh Lipo cell in the Oura Ring 5. (Credit: iFixit)
The tiny 10.5 mAh Lipo cell in the Oura Ring 5. (Credit: iFixit)

The subject of the teardown video is the Oura Ring 5, a $400 smart ring that’s designed to track your vitals much like a wrist-worn fitness tracker — just in a much smaller package. This metal-and-epoxy sandwich can definitely survive a good rain shower and washing of hands, but to get to the internals rather forceful methods were needed, unlike previous Oura and Samsung smart rings where some applied heat was enough.

In the Ring 5’s case even more heat was needed to make the inner ring start to slide out, but by that point the Li-ion battery inside had already popped from the heat. The inner ring then got stuck and more violence was required to continue the disassembly and get to the super-tiny, 10.5 mAh battery. Of course, at this point the smart ring really won’t be getting back together, never mind still work or be waterproof, which is a central issue with these smart rings.

With the EU’s February 2027 deadline for user-replaceable batteries looming on the horizon, it’ll be interesting to see whether devices like this can squeeze into an exception category, or whether manufacturers will have to massively redesign or stop selling these devices to this rather large market. So far this particular regulation has already forced Nintendo to make a special Switch 2 console for the EU.

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A General Purpose Pi Zero Device For IoT

By now we’re all used to single board computers such as the Raspberry Pi Zero, but it’s likely we’ve all been frustrated at times by the number of support components required to use one. This becomes ever more annoying out in the field away from a handy HDMI, USB desktop, and power supply.

The Edgeberry Zero is an attempt to tackle this by mating a Raspberry Pi Zero with a PCB holding a robust power supply and interface connector, all together in a case. better still it comes with Edgeberry Hub, a software management interface.

It appears to be a commercially available product, but it’s Open Source Hardware Association (OSHWA) certified and everything is available in a GitHub repository. Looking at it from a Hackaday perspective it’s hardly the first power supply support board we’ve seen for a Pi, but its approach of making its own expansion module format is an interesting choice. To us they are reminiscent of Game Boy cartridges in the way they slide into a slot in the case.

We like the general idea behind the Edgeberry Zero, but whether it offers enough differentiation from packaging up a Zero with cables and duct tape is up to you.

Making Old Computers Count To A Million

How fast can you count to a million? It would probably take you a while. A computer could certainly do it faster. Indeed, the The National Museum of Computing figured it could actually prove to be a simple but useful benchmark for comparing computers over many eras and architectures. Thus was born the Million Measure.

The intention was to develop a benchmark that could run on just about anything considered a “computer.” As explained in a recent talk, the Million Measure can be run quite simply on anything from an ancient World War II computer like Colossus, to a modern Raspberry Pi. There are no complicated algorithms that need optimization, nor architecture-specific code required to do the job. The museum also found it to be a useful way to figure out which computers in their collection were actually working at any given time. Early computers from the mid-20th century reported benchmark times in minutes, while a 1995 BeBox is the fastest machine tested so far at 0.004 seconds.

It’s not a particularly useful measure for modern machines, which are so fast as to make the test difficult to parse in an intuitive way. But if you’re working with today’s hardware, there are other techniques you can use. Video after the break.

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