The much-maligned Caps Lock key has been causing problems for decades, and its continued existence is controversial enough that Google decided to drop it all together in their Chromebooks. Until the rest of the industry decides to follow their lead, they’ll likely be no shortage of awkward emails or overly aggressive comments that are the direct result of this treacherous key.
But [Glen Akins] thinks he has the solution. His creation is a tiny little USB notification device that has only one purpose: to make a terrible noise as long as the Caps Lock key is engaged. Think of it like the little indicator LED on your keyboard, but one that makes a terrible screeching noise that you simply can’t ignore. This is made possible by the fact that the Caps Lock status is handled at the OS level rather than the local input device.
The notifier is built around the PIC16F1459, as it allowed him to implement USB 2.0 while keeping the part count low. Beyond the PIC, the board uses a handful of passives and a transistor to drive the buzzer from a PWM signal. To avoid duplicated effort, everything was designed to fit inside the enclosure he already developed for his single-key keyboard that we covered last year. [Glen] and a fellow coworker from Keysight put together an excellent video on the creation and use of the buzzer that you can see after the break.
On the other end of the spectrum, and even smaller, is the “USB Capslocker” which is designed to weaponize this already troublesome feature of your keyboard.
Continue reading “Break The Caps Lock Habit With This Annoying Buzzer”
Planning a game of Hacker Jeopardy at your next meetup? You’re going to want some proper buzzers to complete the experience, but why buy when you can build? [Flute Systems] has released an open source DIY game buzzer system based on the Arduino that will help instantly elevate your game. Certainly beats just yelling across the room.
The design has been made to be as easily replicable as possible: as long as you’ve got access to a 3D printer to run off the enclosures for the buzzers and base station, you’ll be able to follow along no problem. The rest of the project consists of modular components put together with jumper wires and scraps of perfboard. Granted it might not be the most elegant solution, but there’s something to be said for projects that beginners and old salts alike can complete.
Each buzzer consists of an Arduino Pro Mini 3.3 V, a nRF24L01, and of course a big pushbutton on the top. Each one is powered by a 110 mAh 3.7 V LiPo battery, though [Flute Systems] notes that the current version of the buzzer can’t actually recharge it. You’ll need to pull the pack out and charge it manually once and awhile. Thankfully, the printed enclosure features a very clever twist-lock mechanism which makes it easy to open anytime you need to poke at the internals.
The base station uses the 5 V version of the Pro Mini, with a Adafruit PowerBoost 1000C to step up the voltage from its 2,000 mAh battery. Of course it also has a nRF24L01, and also adds a buzzer and twin four digit seven-segment LED displays. [Flute Systems] says you can expect about five hours of runtime for the base station.
An especially nice feature of this setup is that the eight digit display allows the base station to show the number of each button in the order it was received. So rather than just getting a display of who buzzed in first, you can see the chronological order in which all eight buttons were pressed. Coming up with clever applications for this capability is left as an exercise for the reader.
Of course, there’s more than one way to build a buzzer. If you don’t like the way [Flute Systems] did it, then check out this version that uses 900 MHz radios and an OLED to show the results.
There’s perhaps no sound more recognizable than the frantic clicking of a Geiger counter. Not because this is some post-apocalyptic world in which everyone is personally acquainted with the operation of said devices, but because it’s such a common effect used in many movies, TV shows, and video games. If somebody hears that noise, even if it doesn’t really make sense in context, they know things are about to get serious.
Capitalizing on this phenomena, [Anton Haidai] has put together a quick hack which turns the ESP8266 into a “Geiger counter” for WiFi. Rather than detecting radiation, the gadget picks up on the strongest nearby WiFi signal and will start clicking in response to signal strength. As the signal gets stronger, so does the clicking. While primarily a novelty, it’s an interesting idea that could potentially be useful for things like fox hunting.
The hardware is really about as simple as it gets, just a basic buzzer attached to one of the digital pins on a NodeMCU development board. This project is more of a proof of concept, but if it were to be developed further it would be interesting to see the electronics placed into a 3D printed replica of one of the old Civil Defense Geiger counters. Perhaps even integrating an analog gauge that can bounce around in response to signal strength.
Software-wise there is the option of locking onto one single network SSID or allowing the device to find the strongest network in the area. Even if you’re not in the market for a chirping WiFi detector, the code is a good example of how you can detect signal RSSI and act on it accordingly; a neat trick which might come in handy in a future project.
If you’re more interested in the real thing, we’ve got plenty of DIY Geiger counters in the archive for you to check out. From diminutive builds that can be mounted to the top of a 9V battery to high-tech solid state versions with touch screen interfaces, you should have plenty of inspiration if you’re looking to kit yourself out before your next drive through the Chernobyl Exclusion Zone.
Continue reading “Duck And Cover With This WiFi “Geiger Counter””
Sometimes, we need devices to notify us of something. The oven timer is going off. Your phone has a push notification. The smoke detector battery is getting low. All of these problems can be solved with a buzzer or an LED. It’s a simple and cheap problem to solve.
But what if you need to know if something’s wrong with a diesel engine that throwing out 90 dB of noise? What if you’re not guaranteed to be around that engine? What if you need to tell everyone within a half mile that something is wrong. Again, LEDs and beepers, but the standard, off-the-shelf implementation isn’t going to cut it. You need massive amounts of buzzers and LEDs, and you’re going to need to drive them all with some reasonably high current. How do you solve that problem?
This is the problem [Tegwyn] had to solve for another one of his Hackaday Prize entries. The solution is what you would expect — buzzers and LEDs — but he’s putting some serious current behind these devices. There are, in fact, thermal considerations taken into account when you’re beeping this many buzzers.
The LEDs for this project are a handful of blindingly bright 1209 and 1206 SMD parts, and the buzzer is an obnoxiously loud SMD 97 dB buzzer. There are eight buzzers on this board. So, how do you drive these power-hungry devices? [Tegwyn] is using an L293E half-bridge motor driver, in a ‘Power-DIP’ package for relatively effective heat dissipation. Does it work? Oh, yes, and it’s very annoying. Take a look at the video below and judge for yourself. You can, indeed, make something louder and more annoying by adding more power.
Continue reading “The Quest For High Powered Blinky And Buzzing”
[Tadas Ustinavičius] writes in to tell us of his latest project, which combines his two great loves of open source and annoying people: OpenKobold. Named after the German mythical spirit that haunts people’s homes, this tiny device is fully open source (hardware and software) and ready to torment your friends and family for up to a year on a CR1220 battery.
The design of the OpenKobold is quite simple, and the open source nature of the project makes this an excellent case study for turning an idea into a fully functional physical object.
Beyond the battery and the buzzer module, the OpenKobold utilizes a PIC12F675, a transistor, and a few passive components. This spartan design allows for a PCB that measures only 25 x 20 mm, making it very easy to hide but fiendishly difficult to try to track down later on.
But the real magic is in the software. The firmware that [Tadas] has written for the PIC not only randomizes how often the buzzer goes off, but how long it will sound for. This makes predicting the OpenKobold with any sort of accuracy very difficult, confounding the poor soul who’s searching their home or office for this maddening little device.
Hackers have a long and storied history of creating elaborate pranks, putting the OpenKobold in very good company. From randomly replaying signals from a remote control to building robotic cardboard burglars, we’ve seen our fair share of elaborate pranks from the community.
Reaching the end of a spool of filament when 3D printing is inevitable. The result ranges from minor annoyance to ruined print. Recently, I needed to print a number of large jobs that used just over half a spool of plastic each. Unwilling to start every print with a fresh spool (and shelve a 60% used one afterward), I had a problem to solve. What my 3D printer needed was filament monitor, or at least that’s what I thought.
After reviewing some projects and aftermarket options, I ended up making my own. Like most prototypes, it wasn’t an instant success, but that’s fine. One of the goals of prototyping is not only to validate that the problems you’re solving are the same ones you think exist, but also to force other problems and issues you may not have considered to the surface. Failure is only a waste if nothing is learned, and the faster and cheaper that learning happens, the better.
Sensible design steps also help minimize waste, so I started by looking at what kind of solutions already existed.
Continue reading “Let’s Prototype! This Filament End Needs 80 Decibels”
TV game shows follow a formula that hasn’t changed much in sixty years. The celebrity presenter, the glamorous assistant, the catch phrases, the gaudy plywood sets, the nervous contestants, and of course the buzzers.
If you want to do a trivia quiz of your own it’s easy enough to dispense with presenter, assistant, set, and catch phrase, but as well as the contestants you’ll still need the buzzers. You can make a mess of wires that the TV technicians of old would have concealed within that set, but in your home or at the pub that could rapidly become inconvenient.
[Larry] solved his trivia game buzzer problems by building a wireless buzzer set. It features 3D printed enclosures containing Adafruit Feather microcontrollers, and instead of wires it uses RFM69 900MHz radio modules. The master unit displays the quickest contestant on an OLED screen, it features a low power standby mode between button presses to save battery power, and care has been taken to add a random timing to button presses to try to avoid collisions.
The buttons themselves started with a 3D printed button working a single tactile switch, but moved to a set of three switches in a triangle after edge presses failed to activate the single switch.
We’ve featured a wired game show buzzer before, but for the complete game show experience how about this countdown timer?