[Reinhard] has a great collection of DIY SCUBA projects. One interesting hack he put together is a soft start circuit to improve the life of the bulb in a flashlight. Despite LEDs getting cheaper, MR16 halogens are dirt cheap and put out some serious lumens.
diy447 Articles
3 Liter Homebrew Beer Keg
Beer kegs are several things. They are expensive, heavy, but most importantly delicious. We found a nice guide for creating your own 3 liter beer keg. This is an inexpensive solution for homebrewers looking to keg their own beer.
The guide goes into detail on assembly and parts needed to create the bottle adapter. Most of the parts can be picked up locally or through MoreBeer.com. CO2 cartridges are used to pressurize the bottle. To keep everything cool you can use a standard water cooler with a few simple modifications. The 3 liter bottle is too tall for some coolers so you’ll need to cut a hole in the lid. Add a piece of aluminum covered styrofoam to the top and bottom, toss in some ice, and your brew should stay cold for about 3 hours.
The author does note that this is not recommended for long term storage. So drink up!
Hydrophone
Chances are you’ve never wondered what your goldfish is trying to say, but if you have (or if you just want a project), check out this DIY hydrophone.
You will need a computer microphone, vegetable oil, plastic wrap, scissors, solder, and a small unused plastic bottle. Solder the mic capsule to an appropriate length of cable and test. The entire assembly can then be submerged in vegetable oil inside a plastic bottle. Yes, vegetable oil. Seal the bottle and you’re done.
DIY Slingbox
[David] took some interesting steps to put together his own Slingbox-ish setup. He used a Mac mini running Quicktime Broadcaster to capture the stream from a Firewire video camera which his cable/satellite receiver is plugged into. You’ll have to use an OS X machine, but that’s not too difficult these days. Broadcaster is about the simplest way to capture from Firewire and stream. We’re using it in our own office to multicast the signal from a Canadian satellite box.
Picaxe Tachometer
It might seem like we’re on a vehicle hacking kick this weekend, but [Rex] built an excellent custom digital tach for his race car. It uses the classic seven segment displays, a PICAXE microcontroller and works with most engines. He’s released full source and PC board designs to boot. This looks like a great little tachometer project for you microcontoller fiends out there.
GSM Remote Control Project
It’s been a while since we’d seen any new SMS/GSM/serial remote interface projects. [Emanuele] sent in his version of a project to do just that. It uses a PIC16F84 and will send or receive commands. A pair of relays provide options for controlling whatever you want to hook it up to. You’ll need a login, but he’s released the full schematics and firmware. He developed this to find uses for old phones, but an alternative is to pick up a cheap calling card cell and dedicate it to a project like this. This seems like a great way to add an out of band alarm system to your house/car/robotic minion.
Make An ECG With Your Sound Card
[Marcus] sent in his work on making ECGs. His first one was inspired by [Jason]’s. Believe it or not, you can build this thing for under $5. After getting it semi-functional, he decided to pick up a cheap one and mod it for PC input via the sound card. (There are plenty of sound card oscilloscope projects that will work for this.) Remember kids, don’t go sticking electrodes on anyone unless you know what you’re doing: correctly placed electrical shocks (even low power ones) can be deadly.
