(Do Breadboards Dream Of) Electric Jam

IT LIVES!


Last Saturday, I finished Make's crackerbox amp project. This is extremely exciting, as it represents a) a successful first foray into the twin lands of circuit diagrams and building electronics from scratch, and b) the actualization of my own electric mandolin!

Janky janky janky. But it works! (I had very limited wire resources... hence, everything is the same color.)

This soldering job reminds me of Kate Beaton's fat pony: ugly and incompetent, but kind of endearing...

While Make seems to have some kind of sponsorship thing with Radio Shack, I don't recommend going there for parts. I moseyed down there one evening, and walked out feeling like I'd lost two hours (including bus time) and spent twice as much as I should've for the components I got. Even if you go online to avoid getting ripped off as much, it could easily cost more than $5 if you don't have most of the stuff already on hand. Still, no complaints - I ended up with this...

:)

The best reference material came from http://www.kpsec.freeuk.com/ . Amazing resource for semi-newcomers to the field of electronic jiggery-pokery. I also highly recommend checking out cairn's comments / linked PCB layout pic on the article page. While it was fun to slowly learn how to read the circuit diagram, at times it got extremely frustrating; I found that layout diagram once I was done, and kinda wished I'd had it all along. (Still, it was gratifying to turn the thing on and have noise come out, when I'd wondered if it would do anything but set the carpet on fire.)

With the piezo mounted! I tried poking/cutting holes in the speaker cone for more distortion, but it doesn't seem to make much of a difference... perhaps because I only have an 8-ohm speaker. It came from the local Kiwanis rummage sale - they have a bunch, and I paid a solitary buck for this one.

This amp exists mainly to give grittiness and edge to the mandolin, and that it does, most noticeably in the upper registers. I chose to use surface-mounted pickups because there's no way I'm taking a drill to the mandolin. So I'm going with a piezo wired to a 1/4" plug, courtesy of the excellent Matt Endahl.

Next step: build a case for it. I settled on some 2-walled plastic with linear cells, which David and I pulled out of the art museum dumpster a while back.

Piezo pickup with plug, duct tape, box cutter, Sharpie, nail sink, amp, plastic.

Cut the plastic into three panels, for optimal stability (that whole 3-legs-don't-wobble thing)... plus mega style points.

Top and bottom covers (the top flaps open); speaker hole cutout.

Duct tape "hammer" + nail sink + needlenose pliers -> easy holes, exactly the right size.

Loud = volume, Angry = gain :)

A lot of people asked about volume vs. gain. As I understand it, the chip already amplifies input sound by a certain amount. The gain feeds from the chip back into it, so that basically controls how much the chip amplifies the signal (sound). (Past a certain level, this creates clipping, which makes it sound gritty.) The volume is between the chip and the speaker ("after" the chip), so it controls how much of this already-amplified signal is put through the speaker.

Left side: on/off toggle, 1/4" jack
Center: volume rheostat, gain potentiometer
Right: speaker
Bottom: PCB, 9V battery

Finished! Here's a short sound sample with the mandolin. There are some images up already on Facebook, as I brought it to Build Night last night at AHA...

Rocking out (as best I am able) at the shop.

We also taped it up to the illustrious Amanda's amazing propane tank steel drum. That thing sounds amazing, though as with the mandolin, only the higher registers worked with the amp's distortion. Apparently, I can switch out one of the capacitors, and it'll pick up more bass... so I guess that's a logical next step with this thing. I already tried hooking up some red LEDs inline with the speaker (so they'd pulse along with the sound), but alas, they were too much of a voltage drain and barely any sound came out.

The last couple of photos are from AHA's Facebook page; I believe they were taken by Josh, one of the proprietors of Digital Ops, our venue. I am inexpressibly happy that this space, the group, and the people in it exist. Dudes are seriously awesome.

Nobody understands meeee

...though mainly because I sing in made-up languages.

I've been having pretty good times lately. The days are particularly grand when I can get a reservation for the V-Room (UM's sound recording booth). I finally recorded three folk songs I wrote while studying abroad in 2008... the vocals are dodgy as always, but I think the language alone gives these interest. They're written in my conlang, mazlaani. The tunes are stolen from other places; lyrics and loose translations follow... click the song titles to download, or here to listen to all of them on Posterous.

Inothaye eila hi fari - Tune: Navan, "Seoithín, Seothó"

Inothaye eila hi fari A’santu mari imkarenni Inothaye eila hi fari Kaadie tsuoheta leme eiyon Xiyora lorelea oreni Lentah pakaiyu sefura faa siten Xiyora lorelea oreni S’akal naarana kte’u Inothaye eila hi fari A’santu mari imkarenni Inothaye eila hi fari Kiie xituran oreni ridae.

To wander this land is good This is a place of peace To wander this land is good Green leaves filter creamy light I drink in the richness of the days My feet walk in cool water I drink in the richness of the days High sunlight warms my skin To wander this land is good This is a place of peace To wander this land is good And I have days to wander.

Chilun tumnanaii - The Chieftains, "Don Oiche Ud I mBeithil"

Elemnen kiranaiyo Kinarolan s’amna me Ruuara-tsorun xala, A’sachti faa lihte hou. A’quuro s’idusa faa Saahta rochai’an; Janaï-to lonn faa charam A’chairechta kummnaou.

The embers of summer sleep under fallen leaves When I inhale, I awaken and my breath is mist on the wind. A fire begins to ignite itself in the air; Sparks drift red from high branches in the twilight.

As'ailu xirhara lani - Ugnëlakis su Kûlgrinda, "Skauda Galvelá, Negaliu"

As’ailu xirhara lani Fairech naarai tumnanaii Xolts’e o rinta leai Reiya petuvin xani, pexeiya Inlaat xe xiute raas’in Rilun, razlaani a’xalsin S’e o s’inna kinuta’u Faolan, o eila-urun xa s’inna Pala’u tchenden nolurinna Xatou as’tir tuorunna Qulann'u s’estoh yunao Lechat’u seiyonna ochai O as’ach as’ailra saati? Taapra canssto, taapra s’altï? Tsuohe-urun a laanti; Tukran-to s’aarai eila...

From my window I see them, Sparkling with autumn sunlight. I would go and run with them, but cannot; it is not given to me... How can I stay and whisper? Now I want to speak, to sing. The world will see my heart beating! The whole world will see me. My drum is the storm’s lightning; I wear the mountain’s gale. My music is the beating rain, My torch is the moon’s flame. Will my eyes turn back to the window? Is home a friend or an enemy? Now all the leaves are falling, The world gleams copper...

Someday I will add backing to this song; right now, I'm thinking tambourine, electric mandolin, and electric mediocre viola. (More on these later...)

Upon reflection, I think I subconsciously stole a couple of words from Elvish: check "laanti" (they fall), with Tolkien's "lantar" (same), as well as "oren"/"aurë" (day). This is not at all surprising, and as any giant dork will observe, the themes are also pretty similar. I wrote a lot about autumn because I had none that year, being in the southern hemisphere for five months; the vocabulary is also limited, because of the size of the language so far.

•••••••••••••

There's more in the offing, but I can't give away all my secrets at once. I'm planning some fun stuff for the Maker Faires this summer (A2 Mini and MakerCity in Detroit)... definitely working with the AHA! Shop, possibly the Hands-On Museum, and/or a couple other excellent peoples. It will be a good season.

[Side note: AUGH FORMATTING... I will try and fix this, but no promises. ;_;]

Juggling balls (Part 2)

These juggling balls are more time- and labor-intensive than the others, but you end up with a much warmer, more personal final product. They're basically hacky sacks, but for juggling you need 3+.

My first attempt / only complete set so far.

There are various ways of making these; the general idea is that you're making a soft cube, so you need six squares in some configuration, plus some space for the stitches to hold. I use two rectangles of suede for each ball, each 3 squares long (kind of like baseballs). You can also use three rectangles of two each, or two L-shaped pieces of 3 each. Or whatever else your little heart desires. All it really affects is the pattern of the colors.

1 red-orange and 1 sage green for each ball. The balls in my original set are filled with black beans, which produces a very pleasant noise. Now I'm trying to make some with jingly bells inside, which will sound sort of rattly when muted by the stuffing... kind of meh, but it'll provide variation. These are for use in juggling rhythms (I've gotten a bunch further since that video... exciting).

Materials!

I'm using doubled thread to sew the edges together, with about 1/4"-1/2" of edging. As with most needle-and-thread projects, this is sewn inside out, except for an opening, then inverted and finished.

Halfway through...

End of each rectangle attaches to the middle third of the other. Suede is a bit more finicky than the cloth I used before; I had to cut a small triangle from each straight edge where it folded around the corner of the other rectangle.

Flipped...

...and inverted. This is just to show what it should look like - a couple more sides need to be sewn before this can be finished. Not all my projects can be fantastic successes, and I ended up abandoning this ball because the suede was too thick and stiff to invert through the hole I had left, at least without undoing a lot of previous stitching. This also happened because I used smaller rectangles than before, which provides less leeway: 1.5-inch squares (so 5.5" x 2.5" rectangles, including 1/2" of slip), instead of 2-inch squares (7" x 3" rectangles). I didn't want to have to stitch up a whole side from the outside, as my attempts at "pretty stitches" usually produce the following:

These are the stitched-up holes from the first set, after stuffing the stuffing in. (Note on that: put in much more stuffing than you think you need, so that the ball is quite taut. Failure to do so will resort in a loose final product that expresses ennui, rather than exuberance. You want EXUBERANT BALLS.)

I'm happy sticking with these ones, as they are very aesthetically pleasing to me. Each has one rectangle of red-on-blue brocade, and for the other rectangle, they have burgundy suede, iridescent red/black cloth, and the reverse of the brocade (blue on red). Hey kids, patterning is cool. B)

Ugly stitches: EXTREME CLOSEUP

Holograms!

A full set of awesome photos to accompany this can be found on Facebook (public link). There is some basic information there; this entry is more in-depth.

Feeling artsy-fartsy? Wanna play with LASERS? Make holograms! (Disclaimer: this actually takes quite a bit of equipment, which I sadly lack in any independent sense...)

This is the perfect art for people like me: arcane, extremely sensitive, involving complex machinery and glass plates, shrouded in velvety darkness... there are lenses to adjust and light beams to guide, and at the end, a 3D illusion is captured in your hands.

These holograms (specifically, Denisyuk-type reflection holograms) are physically composed similarly to photographs: a light-sensitive emulsion in a thin layer atop a flat medium. In photos, of course, there's usually a middle step (the negative), and you end up with light-and-dark patterns on paper, whereas in holograms, the light produces ridges in the emulsion that act as highly complex lenses on a glass plate. Technically, the emulsion is also on the back of the plate - with the emulsion on top, you see the reverse image. You can see a "larger" part of a hologram from a small shard because it compares somewhat to a flashlight: your view of the object in that case is akin to a shaft of light beaming into darkness (anything that is not exposed emulsion). The hologram records the interactions between the reference beam, or the spread-out direct laser beam (which, when you view it, is replaced by your light source) and the object beam, the light reflected back off of the object (which becomes the image you see). You are viewing a reconstruction of how the light reflects off of each part of the object. Since I was using a red laser, the finished hologram reflects this same wavelength of light - so the image looks red. Also, because of how it is constructed, a finished hologram is best viewed under light from a compact point source (like an incandescent bulb).

You may know that the word "camera" is short for "camera obscura", or dark room. Well, when you take a hologram, the entire room literally is the camera, and it contains the plate (vaguely analogous to photo film), darkness, the light source, and your subject. Your setup includes a laser, a shutter blocking the beam, a mirror to angle it toward your plate, several baffles to block stray light, a spatial filter, the frame that holds the plate, and then your subject. (A diagram can be found here, though the spatial filter is missing - this is what spreads the beam into a cone.)

The spatial filter is a fun piece of equipment, which can take anywhere from a minute up to several tense, fiddly hours to set up. It's essentially a lens, or set of lenses, and a pinhole that you adjust to spread and focus the laser beam (Mike made ours from old microscopes). The filter has to be aligned vertically and horizontally so that the beam goes straight through, as perfectly as possible, which is the fiddly bit. Once you have this done (on an extremely stable surface), spreading the beam should yield a series of light and dark concentric rings - interference patterns - because the light is passing through a lens. In the center is a bright spot. You move the lens closer to the pinhole until the bright spot is large enough to cover your subject. Then you close the shutter, turn off the lights, set your plate, and leave.

In order to produce a successful hologram of this type, vibrations and environmental light must be minimized. Blocking light is relatively easy: you set up baffles to keep reflected laser light from hitting the plate, turn off the lights, shut the door, turn off the lights in the next room, and shut that door as well. Blocking vibration is more difficult; Mike Hannum, the awesome Residential College photo/holo prof, built three tables in the basement for this specific purpose. Each one has a bottom layer of 6 inner tubes, then layers of sand and tennis balls for dampening, then more sand and a thick slab of slate on top. It is recommended to work at night, when students are moving around less upstairs and the traffic outside quiets down. And once you've set your unexposed plate in the holder, you leave the room for five minutes to allow the air currents to settle before exposing the plate. Yes. The air currents.

(Do you see yet why I love this art?)

I always picked the table with a shutter switch located outside the room, so I wouldn't have to disturb this setup in order to take the image. Depending on the intensity of the light wash and the reflectivity of the subject, I typically exposed plates for between 5 and 30 seconds. Then, I slunk back into the room, blindly put the plate in a dark sealed box, and brought it out, ablaze with premature triumph. Occasionally, I would end up getting foiled somewhere along the way by developing the plate for the wrong amount of time (this also varies, depending upon the exposure time and such)... but I got some really nice ones along the way, and now I've found my favorite test plates from way back. These and some project materials are now up online, though most of my project work and some of my best overall holograms have been stored elsewhere or given away.

If you want to make simple 3D images but don't have the equipment, check out this awesome handmade hologram video David showed me a while ago... Also pretty frickin' sweet.

Juggling balls (Part 1)

Warning: this post may provoke puerile giggling.

Last May, the excellent Bob tried to teach me to juggle. He lent me some balls for the day, and of course I immediately lost one. Now I seem to have recovered from those unfortunate associations, and have been learning to juggle for a couple of weeks. The results are surprisingly marvelous! (YouTube vid. Beware of ball hitting computer at the end...)

These balls are quite heavy, for two reasons: a) it makes them easier to handle as a starting set, and b) the fact that they work my hands/arms is a motivator for practicing. This set is made from latex gloves, filled with (dry) Quikrete. The bag coverings make them easier to handle and much more durable.

Materials: satiny bag, latex glove, Quikrete (and an empty medicine bottle for scooping)

Tie off the fingers.

I used maybe 4 scoops per ball; these photos are of a replacement ball (I lost one), and it ended up larger than the others because I didn't remember how much grit went into the old ones.

Hefty!

Satin-y! (Inside out, so it'll end up pretty. The bag is about twice as large as we need, so I twisted it around and stretched it back over itself, à la breadbags.)

Drawstring pulled tight and knotted; the last step is to tuck it into the fabric so the ball doesn't catch on things.

Final bonus: these make a very satisfying "tup" noise (now that I can actually keep them going without dropping them frequently).

Part the Second coming sometime, in which we explore the more effortful way of making these things...

Sepia!

I found a box of old photography paraphernalia in my family's house; apparently my mom got it at a garage sale some time back. Included are some developing chemicals and flash-pistol cartridges, baffles for creating ornamental borders, etc. (All of this will be documented later.) The information on the flash-pistol cartridge box matches an ad placed in several photography journals from 1909 (go go Gadget websearch!). Included is a half-pound can of "Rumford Baking Powder", emptied out and used to store photo negatives. Some of them are really gorgeous and well-composed. This morning, I got up early and walked through the mist-grey air to scan them... for you!

Below are the negatives; mouse over for positive-adjusted versions! (See what I do for you.)




























Alas, this one didn't come out well, but the negative looks clearer than that; I know I can get a better image. Try, try again...





Clicking -> Picasa album. These are all the negatives - but there is plenty of photo'ing yet to be done! At some point, I'll share pictures of the rest of the stash (containers, etc.). I'm sharing all of these under Creative Commons (I doubt that the mystery photographer is still alive). You can use and alter them however you want, but please give credit.

Percolating.

I haven't finished anything recently, but that certainly doesn't mean I haven't advanced. I have a sort of book-exploration thing I'm working on, involving such delightful things as mirror poems and inter-language homographs. I've stolen most of the plot and characters from my dreams, which is how I'm getting around my general failure at writing fiction. :)

This is also an excuse to work up a bunch of interesting material. Here are some practice pages from almost a year ago now, when I was being all inspired by old manuscripts (I was taking a Medieval Spanish/Arabic literature course at the time):

(Text is Mazlaani, my constructed language.)

(Text is English, written in... well, I don't think we need to give that away. It's a bunch of quotations I like, from a variety of sources.)

(Basically the same thing.)

Here's a chord wheel for transposition and whatnot; there's some kind of book out there, but the author's wheel makes no sense to me. This is what does. It's a bit janky, visually, but it flows in a logical fashion: you start in the center, and go out to see what chords line up harmonically. If your song uses the first and fourth boxes in a radius, they'll be the same interval apart but in a different key for each other radius. It progresses like cello/viola/violin strings: 7 semitones apart, ascending clockwise. I use this because I'm lazy and find complex chords intimidating.