[Dillon] just finished his first project of the summer. It’s a volume units meter for his sound system and it has a few tricks up its sleeve.

He’s driving the rows of LEDs using an AN6884 LED driver chip. It has an integrated amplifier circuit which makes it the perfect part for building a VU display. He had a broken Linksys 5-port switch sitting around which he used as the enclosure for the project. It has just enough room to incorporate a speaker in case he wants to take the meter on the road with him. But when at home he can choose to use his stereo system instead with the flip of a switch. To ensure he’s making the most out of the 5-bit precision he’s included a voltage divider that can be adjusted with a potentiometer. We’ve embedded a video after the break which shows how well it works.

Looking for a bit more inspiration for your own VU meter project? Check out this RGB version.

We never really get bored with remote-controlled rovers around here, especially when they involve reusing some old hardware as well as lasers. [Tycoon] wrote in to share his creation, which he has dubbed “Texas Ranger”.

Texas Ranger is built around an old Linksys WRT54GL router, which provides the rover’s WiFi connectivity as well as the serial interface through which everything else is controlled. The rover features a pair of PIC microcontrollers, which handle all of the servo control as well as telemetry calculations.

An onboard camera gives the operator a driver’s seat view of the action, allowing for precise control of the vehicle. Laser triangulation is used to help measure object distance, and a pair of airsoft pellet guns straddle the camera for whenever [Tycoon] feels like making his presence known. One feature we are especially fond of is the pair of Wii nunchucks which the rover uses to monitor its position. Always aware of its operating angle, it auto-adjusts the camera to compensate for uneven surfaces, guaranteeing that [Tycoon] doesn’t have to tilt his head to see straight.

Keep reading to see a quick demo video he shot of Texas Ranger in action.

Sometimes when we look at a hack, its to see how someone chose those parts for the project. In this case, it would have been hard to see it coming. [Janne Jansson] decided to combine a set of measuring cups, a hacked Linksys NSLU2 NAS, and a PS/2 Mouse together to make a self-contained Wind Speed Sensor for his roof. The measuring cups act as wind catchers, which in turns drives the rotation of one of the mouse ball sensors. This data is then logged and transmitted by the NSLU2. The NSLU2 is running a custom Linux based firmware, similar to how OpenWRT works for wireless routers.

To calibrate the device, he also made the best logical choice: to duct tape it to the hood of his car along with a much more expensive wind sensor and use that data to make his own device as accurate as possible. When placed atop his house with a 1500VA 220V UPS, the device managed 250 days of uptime before meeting its demise. Those 250 days also included 5 days of being frozen solid, yet still transmitting (somewhat meaningless) data. All of the relevant code and build instructions are available, for those of you with similar parts to spare.

[Craig] wanted to use Boxee on his TV but his computer was in a different room. He rigged up a rather dubious method of delivering the A/V signal (this is a hack in the most guttural sense). More interesting to us is his solution for a remote control interface. We’re familiar with building USB connected infrared receivers but [Craig] decided to patch one into the serial connection on his Linksys WRT54G router.

Surprisingly there’s a lot of space in the router case to add more electronics. He connected a 7805 voltage regulator to the 12v supply for the router and used it to power an IR receiver module and an ATmega328. Because the serial port of the router needs 3.3v he uses a zener diode and resistor to drop the communications voltage. By loading Tomato as the router firmware the remote control signals can be communicated back to a python script running on the host machine.

We do have a few opinions about possible improvements. The use of an ATmega328 is about 30kB worth of overkill. We know that software-based usb infrared receivers run on under 2 kilobytes of programming space. Also, the IR receiver module used (TSOP1738) is obsolete. In this case, we might recommend the TSOP34138. By changing to this part and using a low-power AVR you should be able to run off of the router’s 3.3v regulated supply. This would get rid of the additional regulator and prevent adding even more heat inside the router chassis.

But hardware selection arguments aside, we love the creativity of this solution. Nice work!

GNUCITIZEN has posted information on linksys wireless IP camera hacking. It turns out that some models send the administrator user name and password to the computer when the setup wizard requests a connection. In theory, someone could send the request and harvest your passwords wirelessly. This seems like a pretty careless oversight. We would think that linksys will probably remedy this before too long.

Update: Part 2 has been posted.

Update: Part 3 has been posted.

[via Slashdot]