When we published a piece about an ADS-B antenna using a Coke can as a groundplane, Hackaday reader [2ftg] got in contact with us about something with a bit more… stature.
A monopole groundplane antenna is a single vertical conductor mounted on an insulator and rising up above a conductive groundplane. In radio terms the groundplane is supposed to look as something of a mirror, to provide a reflection of what would come from the other half of a dipole were there to be two conductors. You can use anything conductive as your monopole, a piece of wire, (in radio amateur humour) a piece of wet string, or even beer cans. “Beer cans?” you ask incredulously, expecting this to be another joke. Yes, beer cans, and [2ftg] has been good enough to supply us with a few examples. The first is a 57-foot stack of them welded together in the 1950s for use on the 80 metre band ( we suspect steel cans may have been more common than aluminum back then), the second is a more modest erection for the 2 metre band, and the final one consists of photographs only of an HF version that looks a little wavy and whose cans are a little less beery.
The reporting in the 1950s piece is rather cheesy, but does give a reasonable description of it requiring welding rods as reinforcement. It also gives evidence of the antenna’s effectiveness, showing that it could work the world. Hardly surprising, given that a decent monopole is a decent monopole no matter how many pints of ale you have dispatched in its making.
The Coke can ADSB can be seen in all its glory here, and if all this amateur radio business sounds interesting, here’s an introduction.
Beer cans picture: Visitor7 [CC BY-SA 3.0].
Whether coffee, tea, or beer is your jam, brewing is a delicate pas de deux of time and temperature. Proper brewing of any of these beverages can elevate the experience from average to amazing. With this in mind, [Marcelo] created a time and temperature tool to dial in his beer-brewing process.
BrewBuddy is a complex application-specific timer with an integrated thermometer. It lets him program time and temperature profiles for both the mashing process and the boiling process and store up to 10 steps for each. BrewBuddy doesn’t control the brewing temperature, but it does unify temperature-taking and time-marking into one convenient device that can last about 20 hours on a single CR2032.
The system is based on an STM32 and an LMT86 analog temperature sensor which has been modified to sit inside a stainless steel tube. There are four directional buttons to navigate through intuitive menus to set the desired times and temperatures. As each step completes, the status LED lights up and BrewBuddy waits for confirmation via button push before moving on to the next step. If there’s a problem, the timer can be paused and resumed using the up/down buttons. [Marcelo] is working to perfect the case design, but he already has the board files and firmware up on GitHub. Open up a cold one and check out the demo videos after the break.
After boiling and cooling comes fermentation, and that requires careful monitoring of the sugar content. Here’s a tool for that.
Continue reading “BrewBuddy is a Home Brewer’s Best Friend”
Leave it to engineering students to redefine partying. [Hyun], [Justin], and [Daniel] have done exactly that for their final project by building a virtually-controlled robotic arm that plays beer pong.
There are two main parts to this build: a sleeve worn by the user, and the robotic arm itself. The sleeve has IMUs at the elbow and wrist and a PIC32 that calculates their respective angles. The sleeve sends angle data to a second PIC32 where it is translated it into PWM signals and sent to the arm.
There’s a pressure sensor wired sleeve-side that’s worn between forefinger and thumb and functions as a release mechanism. You don’t actually have to fling your forearm forward to get the robot to throw, but you can if you want to. The arm itself is built from three micro servos and mounted for stability. The spoon was a compromise. They tried for a while to mimic fingers, but didn’t have enough time to implement grasping and releasing on top of everything else.
Initially, the team wanted wireless communication between the sleeve and the arm. They got it to work with a pair of XBees, but found that RF was only good for short periods of use. Communication is much smoother over UART, which you can see in the video below.
You don’t have to have a machine shop or even a 3-D printer to build a robot arm. Here’s another bot made from scrap wood whose sole purpose is to dunk tea bags.
Continue reading “A Robot Arm for Virtual Beer Pong”
What’s better than a cool build? A cool build with valuable advice! Add a few flashy pictures and you have [Martin Raynsford]’s Reuleaux triangle coasters blog post. [Martin Raynsford] wanted to share his advice about the importance of using jigs and we’re sold. He was able to make 100 coasters in a single day and if he’s like us, after number ten, the work gets a little hurried and that is when mistakes are made.
Jig is a broad term when it comes to tooling but essentially, it holds your part in place while you work on it. In this case, a jig was made to hold the coaster pieces while they were glued together. [Martin Raynsford] didn’t need any registration marks on the wood so even the back is clean. If you look closely, the coaster is two parts, the frame and the triangle. Each part is three layers and they cannot separated once the glue dries. If any part doesn’t line up properly, the whole coaster is scrap wood.
This robot arm engraved 400 coasters in a day but maybe you would prefer if you simply had your beer delivered to your new coasters.
Continue reading “Reuleaux Coaster”
A well-stocked liquor cabinet is a necessity for the classy gentleman or gentlelady who likes to entertain. Having the proper spirits and mixers on hand to make anything from a martini to a sidecar is always a solid way to ensure guests have a good time at your cocktail party. In the past, a beautifully crafted cherry or walnut liquor cabinet was enough to impress visitors with your affluence. These days, if you don’t want to look like a pauper, you have to take it a step further.
[Elias Bakken] and his uncle [Mike Moulton] have decided to take liquor cabinets into the 21st century with a semi-automatic liquor cabinet called Latskap. The project is still in progress, and in the prototyping stage, but their build log on Hackaday.io is showing a lot of potential. It shouldn’t be long before they have a fully functional prototype finished.
Continue reading “Latskap Semi-Automatic Liquor Cabinet”
If you are a wine, beer, or cider maker, you’ll know the ritual of checking for fermentation. As the yeast does its work of turning sugar into alcohol, carbon dioxide bubbles froth on the surface of your developing brew, and if your fermentation container has an airlock, large bubbles pass through the water within it on a regular basis. Your ears become attuned to the regular “Plop… plop… plop” sound they make, and from their interval you can tell what stage you have reached.
[Chris] automated this listening for fermentation bubbles, placing a microphone next to his airlock and detecting amplitude spikes through two techniques: one using an FFT algorithm and the other a bandpass filter. Both techniques yielded similar graphs for fermentation activity over time.
He has a few ideas for improvement, but notes that his system is vulnerable to external noises. There is also an admission that using light to detect bubbles might be a more practical solution as we have shown you more than once with other projects, but as with so many projects on these pages, it is the joy of the tech as much as the practicality that matters.
No doubt many Hackaday readers will have tried their hand at home brewing. It’s easy enough, you can start with a can of hopped malt extract and a bag of sugar in a large bucket in your kitchen and achieve a decent enough result. Of course, once you get the taste it’s a field of infinite possibilities, so many enthusiasts go further into the realm of beer making with specialty ingredients and carefully controlled mash tuns.
Such an inductee into the brewery arts is [Christopher Aedo], who has documented his automated brewing system driven by a Raspberry Pi running CraftBeerPi. And it’s an impressive setup, with boil kettle, mash tun, and heat exchanger, a 5KW heating element, and all associated valves, pipes, pumps, and sensors. This ensures consistency and fine control over temperature over the long-term at all stages of the brew, something that would be very difficult to achieve manually at this scale.
The whole brewery is mounted on a cart for portability and has been used for a lot of brew cycles of many different styles. We can’t help a touch of envy at the array of beer taps in his kitchen.
Over the years we’ve brought you a few brewing projects. Another Pi-based setup graced these pages in 2012, as did a brewery using a Lego Mindstorms controller. Top marks go though to the brewer who fought his beer belly through brewing machinery powered by an exercise bike.