Drawing with Sound on an Oscilloscope

No CGI, no digital effects, no computer even; just some electrical testing equipment and an audio recording.  Pretty neat and a lot of fun to watch—so neat and fun that I was, in fact, pretty dubious at first.  So I borrowed an oscilloscope from my local public library and tried it out—AND IT WORKED!

Here’s Jerobeam Fenderson’s explanation of the effect, and another article with several neat videos.

Here’s Fenderson’s older “Drawing Mushrooms” video, which is the one I tested myself:

Metal-on-Metal: Convert an Old Shovel into a DIY Electric Guitar

I love watching Rob Scallon rock out on a shovel guitar.  FYI, this is a totally doable afternoon DIY project for any of you (yes, even you!) or the bored teen in your life.  You can build something just like this (or a hockey-stick bass, an electric broomstick banjo, an axe ax—you get the gag) using the methods laid out in the “$10 Electric Guitar” project in my first book (click here now to get a FREE copy of that project—and, if you’re near Metro Detroit in July, you can come to Motor City Steam Con where I’ll be running a workshop on electric-guitarifying stuff).

Wnat more DIY musical shenanigans?  I’ve got a whole new book of crazy music projects.

Thing I Learned: Check Your Damn Gas Cap!

Vw_engine_check
Yikes! Scary light!

After a long trip, the dashboard of our Scion xD lit up like a Non-Denominational Gift Giving Holiday Display.

🙁

Since this is our “good” car (in contrast to our Prius with the bum AC, which is miserable for summer road trips), I high-tailed it to the mechanic, terrified that we’d done Something Bad to the car that we’re relying to get us through at least another two years (at which time our youngest can enroll in public school, freeing up $1200/month for an auto payment on something big enough for us all to not drive each other to the brink of murder during every damn road trip).

Fortunately:

  1. Our mechanic (Rons’s Garage, God-of-yr-Choosing bless ’em!) is fantastically honest and
  2. It was nothing

So why the light display?

We’d left the gas cap off.

We fueled up as we rolled back into town, as my wife needed the car for work the next day (a ~30 mile drive).  And we hadn’t screwed the cap down all the way.  A loose cap makes the car’s computer believe there’s an air leak somewhere in the fuel system (’cause there is–around the lose cap. If you’re wondering why the car gives a damn: To ruy efficiently, you need to maintain a proper fuel-air ratio in the engine, and it’s easiest to control this if you have a sealed fuel system.  On top of that, petrol fumes are bad news for the environment, so many car’s additionally check for leaks just to make sure you aren’t wrecking up the joint with stray hydrocarbons).

The car can run basically fine like this, and there’s no real danger of damaging the engine.  Put the fuel cap back on, reset the warning light, and all is well.

The lesson:  If your car is throwing a CHECK ENGINE light, make sure the gas cap is tight.  If it’s loose (or you lost it), then tighten it down (or replace it), and keep driving.  If there’s nothing obvious wrong (no sluggishness or weird noises) and it isn’t nearly time for an oil change, you’ll be fine, and the light will reset itself within 100 miles.  If it stays on, then go to the mechanic.

Ron didn’t charge me, because he’s a solid dude (which is why I keep going there).  But plenty of guys would charge you for figuring it out (they did spend time pulling the code from the car’s computer and troubleshooting my dumbassery), and a few would even use this as an excuse to “repair” some “major problem.”

Josh Burker’s Scratchbox Turntable

Josh Burker—an early reviewer of my latest DIY book, Junkyard Jam Band—didn’t just build a sweet-ass Scratchbox (although he did do that)

Josh went one better and adapted it to a hella rad turntable interface.

Oh.

My.

Daaaaaaaamn!

I love this sooooo much! Check it out:

Wanna build your own Scratchbox (or Scratchbox-inspired awesomeness)? Check out my full illustrated Scratchbox build instructions on the MAKE magazine website.

For a brief history of the credit card magstripe that makes this all possible, check out the first bit of this Planet Money podcast: Episode 695: Put A Chip On It : Planet Money : NPR:

(thx Josh!)

DIY Standing Desks

On the off chance you missed the memo: Your chair is killing you!!1!

The tl;dr goes something like this: Human bodies are really ill-served by sitting in a chair for periods longer than ~30 minutes; it tangles up your digestion, causes problems all up and down the spine, and if you are typing at a keyboard is also pretty hard on your blood circulation. Also, “resting” this much strains the heart, as we’re evolved to use the big muscles in our legs to help circulate our blood, thus relieving stress on the heart. We evolved to move around a lot–mostly walking from place to place–not sitting super still while moving our fingers super fast. If you prefer this sort of thing as a totally excessive infographic, the canonical one is to the right.

Anyway, over at the Workantile–which is populated by folks whose jobs are to sit very still while their fingers move very fast–we talk about the health ramifications of our sedentary jobs *a lot*. One of the easiest solutions–in addition to mandating regular perambulations–is to add a standing desk to your office. Our space includes a couple of high cafe tables, as well as one of these bad boys:

This is one of the best store-bought standing desks I’ve seen, because:

  1. It has an adjustable monitor mount: Many folks choose standing desks because looking down at their hands all day is screwing up their necks and backs–looking straight ahead is much more comfortable
  2. It’s convertible: The whole thing can raise and lower so that you can take periodic sitting breaks; shifting from sitting to standing (and being able to sit in multiple different postures) is ideal
  3. It’s flexible: This fella clamps to a wide variety of existing desks, and is really quick and easy to set up

I’m 99 percent sure this particular model (which a member donated) is an “WorkFit-S Single HD Sit-Stand WorstationErgotron WorkFit-S Sit-Stand Workstation,” which costs several hundred dollars.

For those on a budget, their are *tons* of ways to rig up a workable (if, let’s face it, ugly as hell) standing desk. This is a project that’s totally responsive to Roosevelt’s Law of Task Planning (aka Akins Law #34: Do what you can, where you are, with what you have.) Here’s mine:

(The sheet is just there to aid visibility; otherwise it’s hard to see the damn thing against all the clutter hung in my cave)

Yes, this thing–the Fool’s Swing–is ridiculous. I originally hung it up as a platform to test different standing-desk heights in order to determine what I wanted to build (it’s next to my sit-down desk–in ancient, dented Steelcase monster I bought for a dollar–so I can readily shift between sitting and standing). But I discovered that the swing–which took all of five minutes and no dollars to construct–was a good solution for me. Part of the reason this works is that my neck and spine are in great shape–looking down all day doesn’t bother me (also, I touch type, and frequently look away from the screen and just stare into space in front of my as I write); I use a standing desk because working a sit-down job wrecked up my digestion pretty badly (a hereditary thing, as it turns out). The other advantage here is that the swing pushes away from me. I have a tendency to put too much weight on my wrists and lean into them, and the swing doesn’t let me do that. My wife constantly predicts that this arrangement is going to end in a computer-dumping disaster, but it’s been a year and some change, and I’ve never even had a close call. Seeing as how it is basically the same structure as swings I’ve hung–which have put up with much greater weight and abuse without collapsing–I’m not that worried.

Another member of our workspace has this rig, which I love:

Totally ad hoc, but it allows him to pace while working, which is brilliant. Again, zero-cost, and under 30 minutes to build.
Another option is just to boost your desk as a whole. One thing I envy here is that he has an entire raised workspace; when I’m revising (which I do on paper) at home, I generally have to sit at my desk; on book projects, this can mean full days seated, which gets pretty miserable by mid-morning. Although this method requires a lighter desk to begin with (my Steelcase would crush those milk crates), it’s another no cost/quick build solution:

Finally, here’s a link to the canonical $22 Standing Desk from Stock IKEA parts. No one I know has built one, every standing-desker I know has been inspired by it.

FYI, if you’re going to shift to standing and you have a hard floor (mine is vinyl tile on concrete), invest in an “anti-fatigue” gel mat. I got a “Martha Stewart” branded one for $20 at the hardware. Your feet and lower back will thank you. (These are also great in the work room and, if you cook a lot, in front of the sink.)

Dirt-Cheap Amplifier Aesthetics and Tweaks: Grills & Fabric, New & Used, Weird-Spec Speakers


One of my goals with the projects in Snip, Burn, Solder, Shred was to present designs that–both in terms of the functional guts and the finish aesthetics–could be adapted to suit both your own tastes and the supplies you could easily get. For example, the grill on the Dirt-Cheap Amp is an old computer power supply fan cover–which just happened to be the perfect size to secure my 8 ohm speaker (itself torn out of a broken Barbie boom box).  I’ve also had good luck pulling grills off of old/broken small appliances I’ve gotten for free as resale shop rejects or garage sale leftovers.  As far as new sources, check out your local hardware store, where there are many neat vent, drain, and recessed-lighting covers (the plumbing, electrical, and HVAC aisles are always profitable places to search for neat fittings, in my experience).

Upholstering Your Amp

Failing all else, you can cover the front of the amp in fabric (as is standard in the old school Fender guitar amps).  When doing a fabric cover, I like to start with a double-layer of nylon window-screen mesh, which protects the paper cone of the speaker from getting dinged.  Double up the mesh, then cut a square at least a few inches bigger than your speaker hole and staple it in place around the perimeter of the screen (you can, of course, cover the entire front of your speaker cabinet in screen, which will make your amp look a bit more pro.  I sort of like the look of the doubled mesh, but if it doesn’t work for you aesthetically, you can recover it with basically any single layer of fabric (going the Fender Tweed Amp road, for example).  In terms of finish, you can pull the fabric all the way around the lid and staple it from behind (thin fabric won’t usually cause you much grief in terms of getting the cigar box to close once you finish).  A few brass-headed furniture tacks added to the edging of the front of the fabric cover, or framing it out in thin strips of wood or brass, will give the amp really slick look.

Using Weird Speakers

Folks occasionally ask me if this design–which calls for an 8 ohm speaker–will work with lower impedance speakers.  I’ve tested this out, and had the amp work perfectly with 3 and 4 ohm speakers I’ve scrounged out of old boom boxes.  I’ve also had decent results with speakers as high as 16 ohms.  So, if you’re salvaging parts, feel free to grab those 3, 4, and 6 ohm speakers as well as the 8s.  If you find your non-standard speaker distorting, you might wanna monkey around with the pin 1 to pin 8 jumper: some amps built around “non-8” speakers work better with pin 1 and pin 8 connect with plain old wire (as in the base design shown in the book), others work better with that connection omitted altogether, and some need the gain-boost that comes with connecting pins 1 and 8 using an electrolytic capacitor (as described in the “Tweaking the Amp” section of that project).

DIY Music Freebies

UPDATE: You can now get a free “Jam Pack” of musical projects from my first two books!