This GLaDOS potato is a lie

Why settle for virtual reality when you can make the digital world into reality? [Josh] wanted to have a GLaDOS potato accompany him through life when not playing Portal 2. He set to work to see what kind of replica prop he could come up with. Judging from the image above, and demo video after the break, he nailed it right in the spud.

There’s no worrying about rot. The potato and a few parts were molded from Sculpey and baked in the oven. Since the fake spud is hollow in the center it’s easy to hide the bits that make it talk. An old MP3 player was loaded with quotes from the game, and plays them back via an LM386 audio amplifier circuit and a speaker hidden below the electronic eye. The eye is lit by five yellow LEDs which are also tied into the amplifier to make them blink and fade with the intensity of the audio signal.

A paint job and the nails and wire really make the build look just right. Now [Josh] needs to host a geek-themed Halloween party so he can really show this off.

[Read more...]

LM386 Altoids tin amp

altoids_amp

Hacker [Dino Segovis] is back again with the fifth installment in his “Hack a Week” series. This time around he has put together a 1/2 watt audio amplifier that would make for a great weekend project. He’s a big fan of the LM386 amplifier chip because it does so much in such a small package. Since it is so versatile, he used it as the centerpiece of his Altoids tin amplifier.

Now an audio amp inside an Altoids tin isn’t exactly a new concept, but [Dino] takes the time to discuss the circuit in detail, which is great for any beginners out there who are looking for a fun and relatively easy project. After a high-speed video of the assembly process he walks us through the completed amp, then treats us to a couple of short demos.

One thing that makes his amp different than others we have seen in the past is the addition of a 1/4” guitar jack, which allows him to use his amplifier as a combo amp/distortion effect box.

It’s another job well done, so be sure to keep reading if you’d like to watch the latest Hack a Week episode in its entirety.

[Read more...]

Pitch shifter makes your band sing higher

[Markus Gritsch] tipped us off about this little module he built to shift the pitch of audio playback. It uses a PIC 24FJ along with a couple of LM386 amplifier chips to manage the input and output signals. At the push of a button, audio being fed through the device can be modulated to a different key without changing the playback rate. Here it’s being used with a iPod but because this device just sits between an audio source and a signal input we wonder if you can have some fun on the cellphone with this circuit?

Check out the video after the break to hear it in action. We must compliment [Markus] on his layout. We haven’t seen the underside of that protoboard but he’s done a great job of fitting everything into a small area. You can find the schematic for the circuit by following the link at the top of this feature. He took a picture of his hand-drawn plans which saves him time from laying it out with something like KiCAD but still gives us the details that we love to see with your projects.

[Read more...]

PIC spectrum analyzer uses Fast Fourier Transform routine

[Simon Inns] just rolled out his latest project, a PIC based spectrum analyzer. He’s using a Fast Fourier Transform routine crafted in C to run as efficiently as possible on the 8-bit chip. The video after the break shows that the results are quite pleasing, with just a bit of noticeable lag between the sound and the waveform representation on the graphic LCD. We found his notes about using an audio amplifier chip to be interesting. He utilizes the properties of an LM386 to move the input signals from a range of -0.5V to +0.5V into a very ADC friendly range of 0-5V.

[Read more...]

Laser mic makes eavesdropping remarkably simple

Here’s a surprisly simple way to build yourself a laser-based listening device. It consists of two modules, a transmitter and a receiver. The transmitter is a set of lasers, one is visible red for aiming, and the other is infrared for measuring the vibration of a surface. Point the transmitter at the window of the room you want to listen in on and the laser can be reflected back to the receiver. The receiver module has a phototransistor to pick up the infrared laser light, and an LM386 audio amplifier to generate the audio signal sent to a pair of headphone. The need to be well-aligned which is easy enough using a pair of tripods. Check out the demo after the break.

Looking for something to do with the leftover laser diodes from this project? Try making yourself a laser microscope.

[Read more...]

Small CNC gadget draws what it hears

This art piece makes drawings based on sound. [Mario Marchese], who is responsible for those illusion props back in february, built this little guy out of a bunch of junk he had lying around. It features four microphones that listen to ambient sound and feed the signal through some LM386 audio power amplifiers. The output is translated into forward, backward, left, and right movements of the writing platform while the pen is fixed in the same position. Despite what we said in the title of the post this isn’t strictly a CNC machine, but more the primordial cousin of one.

Amplifier built inside a 9v battery

It’s pretty creative to use a 9v battery as an enclosure. That’s what [Osgeld] did when building this amplifier. There are several advantages; they’re easy to find, it keeps a bit of the dead battery out of the landfill, and this method provides a built-in connector for a 9v power source. In this case the circuit is built around a LM386 audio amplifier. It’s glued to the back of a potentiometer and wired up with the other components for a package smaller than a quarter. A stereo jack reside in the side of the battery case with a cable and alligator clips for connection with a speaker. Now the amp can be quickly connect to any 4-8 ohm speaker.

Follow

Get every new post delivered to your Inbox.

Join 93,783 other followers