Brewing Beer With A Sous Vide Cooker

February 7, 2015 by Rick Osgood 17 Comments

[Ken] found an interesting use for his sous vide cooker. He’s been using it to help him with his home brewing. It’s unlikely that the manufacturer ever intended it to be used in this manner, but as hackers we don’t really care about warranties.

Beer brewing is as much of an art as it is a science. There are a lot of variables that go into the process, and tweaking any one of them can result in your beer tasting different. There is one process during brewing that is called mashing. Mashing is when you soak malted grains in hot water to pull out the sugar. The amount of sugar that gets extracted is very dependent on how long the grains are soaked, and the temperature of the water. If you want your beer to taste a certain way, then you want to ensure that the water stays at constant, repeatable temperature.

As a home brewer, [Ken] has been using his stove top to heat the water. This gets the water warm, but in order to keep the temperature consistent, he has to constantly monitor the temperature and adjust the knob accordingly. Who wants to sit around and do that all day? He needed something to control the temperature automatically. Enter the sous vide cooker.

Sous vide is a method of cooking in which food is placed into an airtight bag and then submerged in a water bath with very strict temperature control. The process takes a long time to cook the food, but the result is supposed to be meat that is cooked perfectly even while also retaining all of the moisture and juices. [Ken] figured he might be able to use a sous vide cooker to control the temperature of the mash instead of a water bath.

His experiment worked wonderfully. He used the stove top to help get the mash up to the close temperature, then the sous vide cooker was used to fine tune things from there. [Ken] says he was able to achieve 75% efficiency with his mash, which is exactly what he was going for. Continue reading “Brewing Beer With A Sous Vide Cooker” →

Hackintosh Project Looks Like A Mac, Smells Like A Mac…

February 7, 2015 by Rich Bremer 23 Comments

It’s not often that you find a Macintosh dumped out on the side of the road. [GrandpaSquarepants] was one of the lucky individuals that did. Being the good friend that he is, he made his roomy carry the 50 lb behemoth back to their apartment. Not surprisingly, the machine didn’t boot up and ended up sitting around the apartment for a few years.

Fast forward from 2012 to present day and [G.S.] decided it was time to do something with that G5. That “something” wasn’t about fixing it. Instead, it was gutted to turn it into a Macintosh-cased Hackintosh. If you’re unfamiliar with Hackintosh, it’s a term used to describe a project that gets Mac OS to run on non-Apple hardware.

[G.S.] could have just crammed everything into the G5 case and called it a day but he decided to spend the time to make it look supremely presentable. The case was significantly modified to fit the non-Apple computer components, including the addition of a custom rear panel made from aluminum to mount the power supply, cooling fan and to allow access to the motherboard connectors. Take a close look; there are two CPU coolers in there. It was such a close fit that there is only 2.6mm (.1 inch) of clearance between the cooler and the case.

Two Dell U2415 monitors and an Apple wireless keyboard and mouse make up the rest of the setup. Overall, [G.S.] is happy with the final outcome of his project, well… except for the Apple mouse. He says that has got to go!

[via reddit]

How Green Screen Worked Before Computers

February 7, 2015 by Rick Osgood 19 Comments

If you know anything about how films are made then you have probably heard about the “green screen” before. The technique is also known as chroma key compositing, and it’s generally used to merge two images or videos together based on color hues. Usually you see an actor filmed in front of a green background. Using video editing software, the editor can then replace that specific green color with another video clip. This makes it look like the actor is in a completely different environment.

It’s no surprise that with computers, this is a very simple task. Any basic video editing software will include a chroma key function, but have you ever wondered how this was accomplished before computers made it so simple? [Tom Scott] posted a video to explain exactly that.

In the early days of film, the studio could film the actor against an entirely black background. Then, they would copy the film over and over using higher and higher contrasts until they end up with a black background, and a white silhouette of the actor. This film could be used as a matte. Working with an optical printer, the studio could then perform a double exposure to combine film of a background with the film of the actor. You can imagine that this was a much more cumbersome process than making a few mouse clicks.

For the green screen effect, studios could actually use specialized optical filters. They could apply one filter that would ignore a specific wavelength of the color green. Then they could film the actor using that filter. The resulting matte could then be combined with the footage of the actor and the background film using the optical printer. It’s very similar to the older style with the black background.

Electronic analog video has some other interesting tricks to perform the same basic effect. [Tom] explains that the analog signal contained information about the various colors that needed to be displayed on the screen. Electronic circuits were built that could watch for a specific color (green) and replace the signal with one from the background video. Studios even went so far as to record both the actor and a model simultaneously, using two cameras that were mechanically linked together to make the same movements. The signals could then be run through this special circuit and the combined image recorded all simultaneously.

There are a few other examples in the video, and the effects that [Tom] uses to describe these old techniques go a long way to help understand the concepts. It’s crazy to think of how complicated this process can be, when nowadays we can do it in minutes with the computers we already have in our homes. Continue reading “How Green Screen Worked Before Computers” →

Teardown: The Android-powered IPhone Case

February 7, 2015 by Brian Benchoff 17 Comments

Cellphones! Cellphone cases! Now that Radio Shack is kaput we need to pick up the slack!

A company named Oaxis has been making cell phone cases for a while now, and they’ve recently rolled out something rather interesting – a cell phone case with an e-ink screen. It’s an interesting idea and [Anton] did a teardown on two new releases. The first one just sends an image to an e-ink screen, and on paper, that’s all the second one does as well. There’s something special hidden under the hood, though: a low-end Android system. What an age to live in.

Something interesting happened when [Anton] was futzing with the battery for the e-ink iPhone case. Somehow, the device booted into recovery mode. Android recovery mode. Yes, iPhone cases now run Android.

Inside the e-ink iPhone case, [Anton] found a board with a Rockchip RK2818 SoC. This is the same chip that can be found in cheap Android cell phones. There’s only one button on the cell phone case, and connectivity is only provided by Bluetooth LE, but the possibilities for modding a cell phone case are extremely interesting.

Wouldn’t Tweeting In Morse Code Be More Like “Pecking”?

February 6, 2015 by Sarah Petkus 19 Comments

If you find yourself glued to social media and also wish to know Morse code… we can think of no better invention to help hone your skills than the Twitter Telegraph. This vintage to pop culture mashup by [Devon Elliott] is a recent project that uses a sounder from the 19th century to communicate incoming tweets with dots and dashes.

Back in the day when everyone was connected by wire, the sounder was a device on the receiving end of the telegraph which translated the incoming signal to an audible clicking. Two tall coils sat with a metal tab teetering between them. When electricity surged into one of the coils it would magnetize, pulling the tab downward in a pattern which mimicked the incoming current sent from the other end. [Devon] decided to liberate the sounder from its string-and-two-can origins and use a more modern source of input. By adding a FONA board which comes equipped with a SIM card, the device was capable of connecting and receiving data from the Internet. An Arduino is responsible for taking the data received and translating it into Morse code using the Mark Fickett’s Arduinomorse library, and then sending it out through an I/O pin to the sounder itself to be tapped.

The finished project is connected to a cellular network which it uses to receive SMS messages and tweets. By mentioning the handle @ldntelegraphco you can send the Twitter Telegraph your own message which will be tapped in code for everyone in the vicinity to hear… which is worth giving a try for those of you curious types. Lastly, if you have an interest in taking a look at the code for your own use, it is available on [Devon’s] github.

A DIY Pick And Place You Can Build Right Now

February 6, 2015 by Ethan Zonca 32 Comments

There have been quite a few DIY pick and place projects popping up recently, but most of them are limited to conceptual designs or just partially working prototypes. [Juha] wrote in to let us know about his project, LitePlacer, which is a fully functional DIY pick and place machine with working vision that can actually import BOMs and place parts as small as 0402 with pretty good accuracy.

While some other DIY pick and place setups we’ve featured use fairly exotic setups like delta bots, this machine is built around typical grooved bearings and extruded aluminum. The end effector includes a rotating vacuum tip and a camera mounted alongside the tip. The camera provides feedback for locating fiducials and for finding the position of parts. Instead of using feeders for his machine, [Juha] opted to pick parts directly from pieces of cut tape. While this might be inconvenient if you’re placing large quantities of a single part, it helps keep the design simple.

The software that runs the machine is pretty sophisticated. After a bit of configuration it’s able to import a BOM with X/Y information and start placing within seconds. It also uses the camera to calibrate the needle, measure the PCB using the fiducials, and pinpoint the location of cut tape sections.

If you want to build your own machine, [Juha] published detailed instructions that walk you through the entire assembly process. He’s also selling a kit of parts if you don’t want to source everything yourself. Check out the video after the break to see the machine import a BOM and place some parts (all the way down to 0402).

Continue reading “A DIY Pick And Place You Can Build Right Now” →

A Raspberry Pi SID Player

February 6, 2015 by Brian Benchoff 26 Comments

Of all the vintage chiptune machines out there, the Commodore 64 is the most famous. Even 30 years later, there are still massive gatherings dedicated to eeking out the last cycle of processing power and graphics capability from the CPU and the infamous synth-on-a-chip, the SID. [Bob] wanted to build a SID jukebox. A C64 is capable of the job, but if you want to have every SID composition on an SD card and connect that to a network, a Raspberry Pi is the way to go.

The SID chip, in its 6581 or 8580 versions, is controlled directly by poking registers on the chip through the address and data busses. This means a lot of pins, too many for the original Raspi expansion header. That’s not a problem that can’t be solved with a few shift registers, though. The rest of the circuit is an LM386 audio amplifier, an LCD that displays the current song, and a can crystal oscillator for the SID.

Right now everything is wired up on a breadboard, but making this a Raspberry Pi hat would be a rather simple proposition. It’s only a matter of finding a SID with working filters, and if you can manage that, it’s a pretty easy build to replicate. Video below.

Continue reading “A Raspberry Pi SID Player” →