Punch Tape Musical Synth


[Jeri Ellsworth] sent over a 555 design contest entry that struck her as particularly interesting. The Synthanola is a three-channel music synthesizer that accepts input from an old Heathkit paper tape reader. While this hack might seem overly retro, it’s actually an extremely appropriate use of technology, as the Heathkit H-10 and the 555 timer were both popular tech in the 70’s. This retro-focused synth uses fourteen 555 timers, twelve of which are dedicated to synthesizing audio. If this entry does not win the contest, it certainly must be a strong contender for most 555 timers used.

[Thrashbarg] gives a detailed explanation of the logic used to drive the music playback from the punch tape, as well as full circuit diagrams for his entry. So far he has encoded MP3s of Bach’s Invention and Fugue in D Minor to tape, with hopefully more to come. In order to truly appreciate his efforts, the Synthanola should be seen as well as heard. Stick around for a pair of videos of the synth in action.

If you’re interested in seeing more 555 contest entries, be sure to check out some of our previously featured projects.

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38 KHz IR Communications Tutorial

Learning about how infrared remote controls work is a great way to expand your electronics knowledge. That’s because this technology is invisible to our eye, and happening faster than we can comprehend without help from test equipment. This tutorial over at Pyroelectro talks about the theory behind how the data is transferred and shows you how to build a couple of circuits to experiment with and communicate through infrared light transmissions.

Instead of going with an IR receiver module you’ll build your own using a photo-transistor and an operational amplifier. The Opamp is used to amplify and invert the signal picked up from the IR transmission of a common home entertainment remote control. From there the digital signal is read by a PIC 18F452 microcontroller for processing. But if you want to use a different microcontroller there’s still more than enough usable information to get you across the finish line.

Voice-controlled Rolling Robot


[societyofrobots] recently posted an Instructable on how to build a voice controlled robot in just a few hours time. This robot isn’t particularly cheap, weighing in at about $230, but it is a fun project if you have the means. The bot is driven around by a pair of servos, taking their directions from an Axon II MCU. A VRbot voice recognition module is used to listen for commands, enabling the user to record up to 32 custom triggers for directing the robot.

All of the source code for the robot is included, as well as instructions on how to get started programing the microcontroller. The code provides some basic functionality, but there’s likely plenty more that can be done with the powerful on-board ATmega460. While this robot would make for a great beginner/intermediate project as-is, it should be noted that [societyofrobots] manufactures and sells the Axon II, so this Instructable is half guide/half self-promotion. Have any of you had experience with the Axon II? Let us know what you think.

Keep reading to see a video of the build process as well as the robot doing its thing.

Thanks, [Bill Porter].

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Junkyard Fish Tank

So your house looks like a dumping ground for useless junk? Yeah, we know it’s the hacker’s curse… you just can’t stop salvaging stuff. But follow [Pontazy69’s] lead by building something useful out of that junk. He took an old polystyrene box and made it into this fishtank. You can see that the sides and back of the box has gone unaltered, but the front wall is missing. [Pontazy69] marked and cut straight lines while leaving a lip around the edge. Silicone was used to glue some acrylic (or perhaps glass?) to the inside of this lip. Once dried he added another bead around the outside to ensure it doesn’t leak. Few fish would be happy here without some type of filter so he built one of those out of an old plastic bottle and some other pieces. See videos that show you how to build both the tank and the filter after the break.

We love aquarium hacks almost as much as clock hacks. So check out the water exchange system, and a couple of different lighting systems. Then document your own aquarium projects and let us know about them.

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Printing Your Own Guitar Parts

The white parts that make up the body contours of this guitar have been 3D printed to meet [Bård S D’s] personal specifications. He started designing the pieces last year to add to his Zoybar guitar. Each of the three parts has its own function. The tail piece serves as a floor stand, as well as a hook for hanging the instrument upside down. The wide piece at the top gives the player a place to rest the forearm, and the piece at the bottom serves as a cradle to place on your leg, and contains the jack for the guitar’s pickup. You can see him playing the instrument in the video after the break.

We looked for more information on the Zoybar system but it’s a bit hard to get the facts from that website. We know that the 6-string kit comes standard without frets, and it’ll cost you a pretty penny at around $700. But if it performs as a quality instrument the price isn’t too far out of line.

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Guitar-mounted Camera Documents Your Guitar Hero-ness

[The Longhorn Engineer] wanted to record some of his virtual shredding sessions so he built this camera mount for a Guitar Hero controller. It holds the camera about a foot below the bottom of the controller, pointing up at the guitar and its player. Since the camera is held tightly to the guitar this produces an interesting effect of movement in the background while the foreground is completely stationary. He set out to complete the build using just one piece of acrylic and some fasteners but added an aluminum support piece because the prototype had a bit too much flex to it. The video after the break walks you through the design, the build process, and finishes with a test run.

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[robomaniac] shows us some serious application of modern technology with his recent Instructable, (the) Arduino-Fart-O-Meter. The wireless device uses a “perfboard Arduino” to read a remote wired methane sensor, and send data over a nRF2401A radio transceiver.

“The data” is picked up by another Arduino / transceiver combo, which then drives a servo motor connected to the pointer. The meter itself consists of 6 ranges from “Fresh Air” to “Liquid” so there is no doubt in your standing.

The wireless and remote sensor setup makes this an easy device to include into your loved ones chairs while having the meter far enough away (just in case you have to make a run for it). If you want some more accuracy check out the Fart intensity detector we posted about, which adds in temperature and sound to the equation, or how about a chair that twitters your toots?

Join us after the break for a quick video, its a real gas.

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