How many times has this one happened to you? Just coming home from work, you walk in from the garage, settle down, and pick up the newspaper. But wait, did you remember to shut the garage door?
Presenting the open garage door indicator. [xjc2010] chose the simplest circuit possible, using only a switch to turn on and off the setup, an LED acting as the signal, and a transformer/resistor combo to drop the voltage to an acceptable LED friendly 2.8 volts. We don’t like how he strung wire all over his house to place the beacon, and would have preferred something wireless in one way or another, but for under 6 bucks this gets the job done quickly and cheaply. Now if only we could get it to remind us if we turned off the oven while on vacation.
What can you build with a ballpoint pen and some extra parts? [gzip] found himself with a bonus box of right angle switches and other miscellaneous parts and set out to build a joystick. Simple arcade joysticks use switches that are actuated by the movement of the stick and this design embraces the concept. The four tactile switches are mounted on protoboard facing each other with part of a ballpoint pen in the middle. When the pen is moved it presses against one or more switches to close, completing a circuit. For good measure he even incorporated a fire button into the top of the “stick”. Now we just need someone to make this work with a tiny Ms. Pac-Man emulator.
When [linux-works] found himself needing a switch that could convert coax to opto, he made one. The main chip is a cd4052 cmos analog switch, which he says is really cheap. The rest is pretty self explanatory. This setup can switch between 4 different inputs as well as do the coax to opto conversion.
If you are interested in trying out some home automation, but don’t want to get into the potentially dangerous area of hacking your house wiring, consider these servo switches. These allow you to flip a switch, using a servo. They are clean, temporary, and fairly compact. You can purchase them at oomlout.com or download the designs and build your own.
SparkFun’s latest tutorial shows you how to work with relays. A relay is an electrically operated switch. In this case, they’re using it to switch a 120V AC outlet. The article carries the standard warnings about how not to kill yourself with AC (plus some non sequitor linking throughout). As an extra precaution, they chose a GFI outlet. You probably know how a relay works, but it’s worth seeing how they implemented it. They use a transistor to prevent overloading the microcontroller’s GPIO pin. The control pin is pulled to ground to keep the relay off. A diode is placed across the relay coil to manage the power flow when it discharges. An indicator LED is included to show when the relay closes. This is a great foundation for an automation project, or maybe you just want to terrorize your cat.
When you’re prototyping a new project, sometimes all you need is a switch. The folks at oomlout were tired of constantly having to rewire things, so they built a universal switch box for the Arduino. It has five potentiometers plus three switches. They’ve put together a software package that monitors the switches and can show you a live view of the knob positions. Have a look at the video below for a demo.
This is quickly becoming an unintentional “game controller Saturday”. We haven’t been covering the PSP much lately, so this is a treat. AcidMods forum member [Electro] put together a quick guide for adding two missing shoulder buttons to the PSP. The L2 and R2 buttons are used while playing Playstation 1 games and are usually mapped to directions on the joystick. This mod jumps the joystick’s contacts an relocates the buttons to the shoulders. The switches used in the post seem kind of bulky, but you’re free to use anything that fits.
[IronGeek] has published his latest video how-to: DNS Spoofing with Ettercap. Ettercap is designed specifically to perform man in the middle attacks on your local network. It can do ARP poisoning, collect passwords, fingerprint OSes, and content filtering. For DNS spoofing, you just need to edit a config file that defines which domains resolve to which IP addresses. You can use wildcards for the domains. In the video, he uses Linux because the network interfaces are easier to remember. Once you’re done playing with DNS spoofing, remember to flush your local cache otherwise your browser will continue to go to the wrong IP.