Author Archives: KevinB

Basic and Premium StrobeTV

Posted on by KevinB

Do you ever want to watch a movie at home, but can’t decide between your favorite two?  Maybe your favorite TV show is about to start, but you’re still watching a film on DVD?  Perhaps you and a friend can’t agree on which film to watch? Well, you need not fret if you’re an early adopter of StrobeTV – a new device that enables the viewing of TWO films simultaneously on a single television by simply alternating between them!  The basic version features two knobs for fine-tuning your experience.  One sets “impatience,” which is how long you’ll view and listen to one film before switching to the second film.  This can be set from once every10 seconds and mere fractions of a second! The second knob controls “preference” or the relative amount of time spent watching the first or second film – perhaps you want to view the first film 60% of the time, and the second 40%.  Or, might it be 25% first and 75% second?

If you’re the proud owner of the Premium StrobeTV, a world of customization is achievable using the eight three position switches and two knobs.  The upper row of switches configures the experience you’ll enjoy for an amount of time set by the upper knob.  When this time expires, your experience is set by the lower row of switches for the amount of time selected by the lower knob.  Naturally, the process repeats, endlessly alternating between your two chosen forms of entertainment – be that TV, DVD, Netflix, gaming consoles, etc.  Perhaps you feel you’ll miss out on important action while you’re watching one film? Premium StrobeTV allows you to listen to the left and right audio channels of the second film, while you view the image from the first film!  Maybe you’re more comfortable reserving the left speaker for playing the left channel audio for the film you’re not currently viewing?  Or maybe the audio alternates? With StrobeTV, the possibilities are virtually endless.  Premium StrobeTV has an enhanced switching range, from once per 15 seconds to over forty times per second, ensuring you won’t miss a single detail!

Premium StrobeTV features an ingenious 2 meter long  cable that allows the controls to be at your fingertips, while the wiring remains hidden away.  Note that Premium StrobeTV, like its more economical sibling, allows for the switching of four signals: right audio, composite video, left audio, and a forth signal of your choice!

 

Redwood Audio Amplifier

Posted on by KevinB

A few months ago I started collaborating with Jordan Waraksa on a project that is currently on display at the Haggerty Museum of Art, in a show running until the end of December.  He sculpted a pair of wooden acoustic horns called Bellaphone 5 & 6 out of walnut.  Each horn rests on a redwood base that houses a small speaker.  If you visit the Haggerty, you’ll hear the speakers playing songs by Jordan’s band, The Vitrolum Republic.  If you really love the Bellaphones and amplifier, know they are for sale.

I developed and built the electronics for the horn’s amplifier, whose chassis Jordan also sculpted from redwood.  Because the chassis is wood and has no vents (for aesthetics), electrical efficiency became a high priority in order to prevent overheating.  I chose to use a Maxim 98400A class D amplifier driven by a high efficiency switching 15V DC power supply.  I added a digital signal processing chip from Analog Devices to increase the bandwidth of the horn and smooth out its frequency response (i.e. to improve the audio fidelity).  Analog’s ADAU1701 is a remarkably powerful chip – it is more than capable of these tasks.  In addition, the 1701 prevents bass notes (frequencies below 100 Hz) from reaching the small speakers (which are incapable of reproducing these low notes), which would otherwise emanate from the horns as distortion.  Finally, the 1701 also adds a small amount of compression, which prevents distortion at the loudest output levels.   The 1701 is actually real-time programmable via a USB connection to a computer running Analog Device’s free SigmaStudio software.  It’s a tremendously user friendly GUI environment with drag and drop audio processing blocks.

Check out the inside of the amplifier as it was being assembled, prior to the addition of many ferrite beads which eliminate the audible noise from the three high efficiency switching power supplies:  One powering the amp, one powering the DSP board, and one continuously charging a Motorola Cliq XT handset playing songs from the Vitrolum Republic.

Here are two more close ups, one of the amplifier:

And one of Bellaphone five and six:

Cacophonator

Posted on by KevinB

I’ve recently made several audio synthesizer / noise generating boxes.  The most recent is the Cacophonator, whose circuit description and board layout are easy to find on the web.  Thanks to Adam for showing me how to etch my own circuit boards – something I can now do quite easily at the Makerspace.  I modified the board layout, drawn in DipTrace, so I could add SIP sockets and pin headers to tidy up the inside of the project box.  The sockets also allow the board to be easily removed, despite the 20 wires running between the board and other components inside the project box.  The  photos below were taken before I modified the circuit by adding a momentary power switch to slowly recharge the giant power supply capacitor if held for a few seconds.  I also added a LM317 adjustable voltage regulator so the power supply voltage can be reduced all the way down to 1 V DC and below.  The sonic complexity of this circuit is surprising considering its small part count, and lowering the power supply voltage further adds to the chaotic behavior of the cacophonator.  Careful inspection of the board will show additional components not associated with the original cacophonator, but are discussed on electro-music.com.  These are used for inputting audio signals (music, for example), which come out the RCA jack quite cacophonated.

 

Makerspace Eight Speaker Super Surround Sound System

Posted on by KevinB

The day has finally arrived: The Makerspace Eight Speaker Super Surround Sound System (MESSSSS) is fully installed, wired and amplified.  This morning MESSSSS reproduced its first 8 channel audio piece, authored using adobe audition and played back by four android devices through four 1/8″ stereo cables feeding the bank of amplifiers.  More integration work remains to be completed (a dedicated computer with an 8 channel sound card plus a patch bay) but the MESSSSS is up and running!

Bay View Gallery Night is Friday, June 3rd at the Makerspace

Posted on by KevinB

Friday, June 3rd is Bay View Gallery Night: The Milwaukee Makerspace is hosting our own artists, and artists from Bay View Arts Guild to show their work. We have over 20 confirmed artists, plus two bands and more!  Stop by the Makerspace between 6pm and 10pm!


BVAG Participants:
Janet Falk / fiber
Karen Costello / jewelry – recycled stuff
Terry Nichash / photography
Ian Pritchard / photography
Donna Pogliano / jewelry
Cali Thomas / paintings
Anita Burgermeister – paintings
Stan Doty – wood carving
Erich Ebert – poetry & installation

MM Participants:
Brent Bublitz – sculpture
Jackie Steffen – illustrationsc
Kevin Bastyr – sound sculpture
Pete Prodoehl – drawing robots
Matt Neesley – sculpture
Amanda Endries – collage
Jason Gessner – interactive audio
Matt Gauger – interactive audio
Ross Oldenburg – interactive audio

Community Participants:
Dani Schmidt – Vase Sculpture
Bill Arthur – Painting
Lisa Sim – jewelry

We also have two bands playing: Makerspace’s own Ross Oldenburg in his band The Plane to Lisbon, followed by Steve Cohen.

Interested in Milwaukee Makerspace Membership or Information?

Posted on by KevinB

Curious about Milwaukee Makerspace Membership after attending our Open House on Saturday? Feel free to attend the weekly meeting held at our space at 3073 S. Chase Ave Building 34. The meeting starts every Tuesday evening at 7 P.M. and lasts about an hour. After the meeting all types of Making will be happening. The Milwaukee Makerspace is also open for prospective-member visits on Thursdays after 7pm on our weekly electronics night – its BYOEP (Bring your own electronics project). Please do stop by to meet the Makers! We hope to see you on an upcoming Tuesday or Thursday night!

Jacob’s Ladder

Posted on by KevinB

In about 30 minutes after the Makerspace meeting on Tuesday, Ross, Jason and I made a Jacob’s Ladder from an old neon light transformer that I brought in, a couple pieces of wood, and some TIG welding aluminum filler rod.

With 110 Volts at its input, the transformer put out 9000 Volts! The arc formed across the gap, but it wasn’t actually a high enough voltage to make the arc ascend the ladder. When I hooked the transformer through a Variac and turned the knob to 130 Volts, the arc began to ascend the ladder – but only a few inches. The obvious solution was to add more voltage, so I hooked another Variac in series with the first, turning this one to 140 Vac. With the output of the transformer a bit under 12000 Volts, the arc ascended over 2 feet up the ladder. Check out the video below showing the arc’s interaction with wood.

Rubens Flame-Tube

Posted on by KevinB

Last Saturday morning I spent 4 hours making a Rubens Tube at the Makerspace while the crew from Pumping Station: One was shooting footage for their documentary entitled The Rebirth of the Maker Movement. Here is the first lighting of the tube:
Milwaukee Makerspace: We play with fire
A Rubens Tube is a pretty flashy piece of physics demo gear that uses fire to show the acoustic standing wave pattern inside an organ-pipe like tube fitted with a loudspeaker at one end. The 48” long, 2.5” diameter tube is filled with propane, which escapes through a series of 50 0.043” diameter holes spaced by 0.9 inches all along the length of the tube. Once the tube is full of propane (with absolutely no air), the 50 propane jets are lit with a striker or match, and all 50 flames have an identical height of 2 or 3 inches. When sound is played though the speaker at one end of the tube, the flame height is modulated by the acoustic pressure from the speaker. When a single tone (sine wave) at a resonance frequency of the system is played though the speaker, the heights of the flames map out the sinusoidal shape along the length of the tube. Playing music with dynamics or signing through the speaker is especially dramatic. I need to spend a few more hours fitting the Rubens Tube with a speaker at the other end and adding an additional propane inlet.

Makerspace Organization

Posted on by KevinB

It was a banner day at the Makerspace for collaboration and organization. After watching forklift safety training materials with Sean, we drove the new forklift (Thanks, Tom!) around the open bay moving pallets around a bit. I then moved around Sean’s and my storage pallet on the racking. I restacked the lumber and extra bench tops so they were out of the way of the forklift:

The above photo shows the four newly installed pallet rack shelves I brought down from from the upstairs storage. I moved Jason’s audio gear to his very own storage pallet (Sorry!). It also shows the bench tops that Brant and Co. recently cut. I finished screwing these sections together with the new 19.2 V Cordless drill that Ben just donated to the space today. Now the bench tops won’t drop through the racking – They’re 16 feet of usable benches!

I also cleaned up the bay – moving the carbon fiber beams under the new bench tops, and moving the extra batteries, motors, pumps, gears and saw to a pallet on the new section of racking. Only the Pots of Gold and saws remain in the cleaned up bay:

After Brant, Ron and I hung the new 4′ by 4′ pegboard that Rich made, I put the second half of the tools up on the pegboard: