“What is My Purpose?” You Amplify and Display Signals.

[Andy_Fuentes22] likes to stream music, but is (understandably) underwhelmed by the sound that comes out of his phone. He wanted to build something that not only looks good, but sounds good. Something that could stream music through a Chromecast or a Raspi, but also take auxiliary input. Something awesome, like the Junkbots Sound System.

The ‘bots, named LR-E (Larry) and R8-CHL (Rachel), aren’t just cool pieces of art. They’re both dead-bug-walking bots with an LM386-based amplifier circuit and an AN6884-based VU meter in their transparent, industrial relay bodies. LR-E is the left channel, and his lovely wife is the right channel. The best part is that they are wired into the circuit through their 3.5mm plug legs and the corresponding jacks mounted in the Altoids tin base.

[Andy] built this labor of love from the ground up. He started with some very nice design sketches and took a bazillion pictures along the way. We think it sounds pretty good, but you can judge for yourself after the break. If VU meters are your jam, here’s another that’s built into the speaker.

Continue reading ““What is My Purpose?” You Amplify and Display Signals.”

SPARC: A Voice Controlled Robot Sings Sweetly in DTMF

One of the recurring themes of science fiction is the robot. From such icons as C-3PO and R2D2 in Star Wars to WALL-E and Eve, robots have always had a certain appeal. Inexpensive microcontrollers like the Arduino have opened up the world of robotics to more people. [JohnFin] has done just this. By linking two Arduinos as the brain, he has created a voice controlled robot he calls S.P.A.R.C. (Sentry/Project Assistant/Robot Companion).

It began when he received a robotic arm for Christmas and was disappointed by it. Instead of simply building a better arm, he got “carried away” and built an entire robot instead. The entire project took three months, most of which he spent learning programming.

SPARC has three sonar sensors for detecting obstacles and movement, an arm and a couple of interchangeable hands for holding objects, and an EasyVR Arduino Shield for the voice control. The robot’s “eyes” are an LED ‘KITT’ scanner and an AN6884 VU meter chip that flashes the “eyes” when the robot speaks. It carries an onboard smartphone to look up weather, play music from the phone’s SD card, and GPS functions.

SPARC can respond to a range of commands and games including “follow me” and “singing.” [JohnFin] has also added a “sequencer” function to record and playback a series of commands. A video of this feature can be found after the break.

Continue reading “SPARC: A Voice Controlled Robot Sings Sweetly in DTMF”

VU meter lives in a Linksys housing

[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.

Continue reading “VU meter lives in a Linksys housing”