If you grew up in the latter part of the 20th century, you didn’t have the Internet we have today — or maybe not at all. What you did have, though, was Radio Shack within an hour’s drive. They sold consumer electronics, of course, but they also sold parts and kits. In addition to specific kits, they always had some versions of a universal kit where lots of components were mounted on a board and you could easily connect and disconnect them to build different things. [RetoSpector78] found a 200-in-1 kit at a thrift store that was exactly like the one he had as a kid and he shares it with us in the video below.
This was a particularly fancy model since it has a nice looking front panel with a few knobs and displays. The book shows you how to make the 200 different projects ranging from metronomes to rain detectors. The projects really fell into several categories. There were practical circuits like radio receivers, test equipment, and transmitters. Then there were games or circuits even the manual called “silly.” In addition, there were circuits to build simply to understand how they work, like flip flops or counters.
Continue reading “There Are 200 Electronic Kits In That Box”
We know the effect of passing white light through a prism and seeing the color spectrum that comes out of the other side. It will not be noticeable to the naked eye, but that rainbow does not fully span the range of [Roy G. Biv]. There are narrowly absent colors which blur together, and those missing portions are a fingerprint of the matter the white light is passing through or bouncing off. Those with a keen eye will recognize that we are talking about spectrophotometry which is identifying those fingerprints and determining what is being observed and how much is under observation. The device which does this is called a spectrometer and [Justin Atkin] invites us along for his build. Video can also be seen below.
Along with the build, we learn how spectrophotometry works, starting with how photons are generated and why gaps appear in the color spectrum. It is all about electrons, which some of our seasoned spectrometer users already know. The build uses a wooden NanoDrop style case cut on a laser engraver. It needs some improvements which are mentioned and shown in the video so you will want to have some aluminum tape on hand. The rest of the bill of materials is covered including “Black 2.0” which claims to be the “mattest, flattest, black acrylic paint.” Maybe that will come in handy for other optical projects. It might be wise to buy first surface mirrors cut to size, but you can always make bespoke mirrors with carefully chosen tools.
Continue reading “Spectrometer Is Inexpensive And Capable”
We hope you have been good this year because we have a list to start your own biology lab and not everything will fit into Santa’s bag (of holding). If you need some last minute goodie points, Santa loves open-source and people who share on our tip line. Our friends at [The Thought Emporium] have compiled a list of the necessary equipment for a biology lab. Chemistry labs-in-a-box have been the inspiration for many young chemists, but there are remarkable differences between a chemistry lab and a biology lab which are explained in the Youtube video linked above and embedded after the break.
If you are preparing to start a laboratory or wondering what to add to your fledging lab, this video is perfect. It comes from the perspective of a hacker not afraid to make tools like his heat block and incubator which should absolutely be built rather than purchased but certain things, like a centrifuge, should be purchased when the lab is mature. In the middle we have the autoclave where a used pressure cooker may do the trick or you may need a full-blown commercial model with lots of space and a high-pressure range.
Maybe this will take some of the mystique out of starting your own lab and help you understand what is happening with a gel dock or why a spectrophotometer is the bee’s knees. There are a handful of other tools not mentioned here so if this is resonating, it will be worth a watch.
Continue reading “Biology Lab on Your Christmas List”
Lab equipment is often expensive, but budgets can be tight and not always up to getting small labs or researchers what they need. That’s why [akshay_d21] designed an Open Source Lab Rocker with a modular tray that uses commonly available hardware and 3D printed parts. The device generates precisely controlled, smooth motion to perform automated mild to moderately aggressive mixing of samples by tilting the attached tray in a see-saw motion. It can accommodate either a beaker or test tubes, but since the tray is modular, different trays can be designed to fit specific needs.
Source code and schematics are available from [akshay_d21]’s Google Drive and the 3D models are also available from the National Institute of Health’s 3D Print Exchange. A demonstration video is embedded below, in which you can see how smooth and controlled the motions are.
Continue reading “Open Source Laboratory Rocker is Super Smooth”
We like to think our readers are on the cutting edge. With the advent of CRISPR kits at home and DIY bio blooming in workshops across the world, we wanted to share a video which may be ahead of its time. [The Thought Emporium] has just shown us a way to store eukaryotic cells at room temperature. His technique is based on a paper published in Nature which he links to from the YouTube page, but you can see his video after the break.
Eukaryotic cells, the kind we are made of, have been transported at low temperatures with techniques like active refrigeration, liquid nitrogen, and dry ice but those come with a host of problems like cost, convenience, and portability. Storing the cells with cryogel has been shown to reliably keep the cells stable for up to a week at a time and [The Thought Emporium] made some in his homemade freeze-dryer which he’s shown us before. The result looks like a potato chip, but is probably less nutrious than astronaut ice cream.
If cell transport doesn’t tickle your fancy, cryogel is fascinating by itself as a durable, lightweight insulator similar to Aerogel. You can make Aerogel at home too.
Continue reading “DIY Cryogel Sustains Live Cells”
It sounds like an overly complicated method a supervillain would use to slowly and painfully eliminate enemies — a chamber with variable oxygen concentration. This automated environmental chamber isn’t for torturing suave MI6 agents, though; rather, it enables cancer research more-or-less on the cheap.
Tasked with building something to let his lab simulate the variable oxygen microenvironments found in some kinds of tumors, [RyanM415] first chose a standard lab incubator as a chamber to mix room air with bottled nitrogen. With a requirement to quickly vary the oxygen concentration from the normal 21% down to zero, he found that the large incubator took far too long to equilibrate, and so he switched to a small acrylic box. Equipped with a mixing fan, the smaller chamber quickly adjusts to setpoints, with an oxygen sensor providing feedback and controlling the gas valves via a pair of Arduinos. It’s quite a contraption, with floating ball flowmeters and stepper-actuated variable gas valves, but the results are impressive. If it weren’t for the $2000 oxygen sensor, [RyanM145] would have brought the whole project in for $500, but at least the lab can use the sensor elsewhere.
Modern biology and chemistry labs are target-rich environments for hacked instrumentation. From DIY incubators to cheap electrophoresis rigs, we’ve got you covered.
Continue reading “Automated Chamber Passes Just the Right Gas”
When you take a microcontroller class in university, one of the early labs they have you drudge through on your way to, promised, mastery over all things embedded, is a tiny music generator.
It’s a more challenging lab than one would expect. It takes understanding the clock of the microcontroller and its sometimes temperamental nature. It takes a clear mental picture of interrupts, and is likely one of the first experiences a burgeoning designer will have worrying about the execution time of one of their loops. Also tables, data structures, and more. It even requires them to go out of their comfort zone a learn about an unrelated field, a challenge often faced in practicing engineering.
Luckily [Łukasz Podkalicki] has done a great job of documenting the adventure. He’s got everything from the schematic and code to the PWM traces on the oscilloscope.
It’s also worth mentioning that he’s got a few other really nice tutorials for the ATtiny13 microcontroller on his blog. A tiny party light generator and a IR receiver among them.