WaitingForFriday’s [Simon Inns] is quite possibly the USB interface and PIC master. This week he let us know about his VU-meter repurposed as a computer performance monitor using a PIC18F2550 and his open source USB Generic HID communication class. With PWM the meter’s needles and RGB LED can be accurately set and even dampened for CPU usage, network usage, HDD utilization, and even memory usage. Oddly enough, in his software we didn’t find the ability to use the device as a VU-meter – go figure.
[Christian Doran] wanted some blinky goodness to go along with the tunes on his PSP. He built a VU meter circuit around a couple of LM324 op-amp chips and fit it into the UMD space on the back of the PSP. Using surface mount LEDs and some fine wire he lined up a string of indicator lights round the circle on the clear UMD cover. As you can see in the video after the break, the back of the case now pulses along with the music.
[Christian] notes that building the VU circuit around an LM3915 would have been much easier but he’s working with what he has on hand. Looks like he achieve the effect he was after. If you want to learn a bit more about how the op-amps work, take a look at the tutorial from our links post.
Hard drive speakers aren’t anything new, but they have yet to be done very professionally. Most hard drive speaker hacks are awesome, but aren’t meant to be a showpiece. [Oliver] took the opportunity to put together a set of 20GB drives and a custom-built acrylic case with a horizontal VU meter up front. The project is well-photographed and documented and can be recreated without the use of laser cutters or other expensive tools. The only thing it’s missing is an iPod dock!
Related: Giant bulb VU meter
The latest Inventgeek project is a 12 outlet control box. They decided to demo it using a giant bulb based VU meter. The control box has 12 individual outlets hooked up to two layers of six solid state relays. [Jared] notes that SSRs can be very expensive, but he purchased his on eBay for ~$10 each. Wiring and installation on this project is incredibly clean and they plan on using the control box for future how-tos. The simple audio circuit used for the VU is based on the LM3915. You’ll find full plans on the site or you can watch the overview video embedded below.
[ricosgoo] wanted a way to stand out at his graduation. We think he succeeded with his graduation gown VU meter. After putting the circuit together at the last minute, he made a mounting harness out of duct tape. The electronics hang like a sash, placing the bulk under his arm where it won’t show through his gown. He mounted a mike towards the neck line so it reacts best to his voice. It was a hit, apparently strangers would come up and make noise just to see the meter go off.
[via Hacked Gadgets]