Monthly Archives: November 2006

The Future Of DK421

November 21, 2006 » Geek

I’m currently re-thinking the future of DK421. It’s the hardware that has become the hang up. I’m 100% sure that the design I have for the pads is physically impossible. In point of fact, the design is mentally obtuse to begin with. A drum stick just doesn’t hit down with any reasonable amount of force. To think it could be enough to move a not insubstantial amount of plywood any real distance was silly. More so considering I also sought to compress four springs.

Where that leaves me is with a strong desire to use piezo transducers, or some other cheap, microphone-like option, combined with either a micro controller or some relays or something. The hard part is I don’t know any electronics really, I’m just winging it so far.

The vector I’d be most happy with pursuing is using an Ardunio board to read the transducers (voltage? wattage? I dunno…) and when they peak a certain amount, fire off some information over a serial connection. The problems are many for this. One, I don’t have a micro controller, and don’t know how to program and use them. Two, I’ve never done any serial port programming, and am not completely sure if it’s even a viable option for passing the data. Three, I don’t know what to measure on the transducers or how to do so. Four, I think Java might be out of the question with the serial. There is a javax.comm, but I’m not so sure about it.

Regardless, I want to try this way. I’ve wanted to buy a micro controller to play with for a while now, and the Ardunio is open-source and way cheaper than a basic stamp setup. I also kinda want to get me C++ back, and maybe learn how to use QT or GTK. This is either going to be long and fun, or die in shame. Going to buy the board tonight I think.

WLAN Router Monitor BASH Script

November 16, 2006 » Geek

I was reading some material on WEP and WPA cracking, and decided to write a monitor for our router. I was curious if anyone other than us hooked up. I’ve turned off the MAC filtering on it and got my BASH script working.

I’m kinda proud of it actually. I wrote it from scratch, just hit up the man pages on my system for hints. I wanted to use lynx -dump on the “Attached Devices” page, but I couldn’t get lynx to authenticate from the command line. I decided to use wget instead, since it worked just fine. I also knew I had html2txt installed from something else, so that was good too.

Here’s the script, password removed of course. The slickness is all in that last line, pardon my WP plug-in’s poor highlighting.

The one tough feature to find was getting wget to print to the stdout instead of to a file. Thats what the -O - does.

It works nice, but it has a lot of extra spacing in it. I tried to do a sed line to filter out multiple newlines, but I’ve never actually used sed, and I couldn’t get it working. Maybe it’s my regex: s/\n{2,}//g. Dunno, not a biggie. I hooked up a cron job for every 15 minutes, we’ll see what I catch (and how bloated that log file will get)

P.S. The router is a NetGear WGR614 v5

P.P.S. I got to thinking about that comment about MAC filtering. With a big network you could camp out with Kismet, grab some attached devices MAC, wait until it disconnects and change your MAC to it’s. While you wait you can crack the WEP too. MAC filtering really isn’t as good as I thought. Same with fakeap. If only one ap has attached devices…uh, that’d be the real one…


November 11, 2006 » Geek

I messed with F-Spot today. Or rather, from about 1:30 to 2:30 this morning. For those too lazy to follow the link, F-Spot is a photo manager, much like Picasa or that iPhoto garbage. Anyway, you can sort, view, crop, enhance and tag the living daylights out of your photo collection with it.

I really like the interface, it’s very intuitive and much like Picasa (or vice versa, I dunno which came first). The tags and filtering are great, and provide nice visual cues for your sorting. There are also numerous editing tools and they seem to work at very respectable speeds, and lossless no less.

My problem is that my pictures are a real mess of folders, and very few are tagged with the correct date and time in the EXIF info. It looks like I’m going to have to go through adding a folder at a time and weeding out dupes and stuff. That might take a while, but I think it will be absolutely worth it. I’m gonna get some sleep now.

Update (11/11/2006)
I went through and added 2878 photos from 2001 – 2006, all the pics I had. I’ve got 20+ different tags. Crazy, it took a while but I think it’ll be worth it if I keep maintaining it with new pictures. Rad.

The First Pad

November 9, 2006 » Geek

Looks like the first pad is going to be the kick drum because I’ve misjudged the whole deal. I went to Ace Hardware today and picked up the stuff. I pretty much just guessed on everything. I bought:

  • Five 5/16″ Bolts, Approx 3″ long @ 0.19 ea
  • Seven 5/16″ Nuts @ 0.07 ea
  • Four Springs @ 0.79 ea
  • Seven 5/16″ Terminal Rings @ 2.49 total

I guessed well on the length of the bolts, the nuts obviously aren’t a guess, neither are the terminal rings. The springs, however, were not a good guess. It’s surprising how much different a spring feels in your hande versus mounted. The ones I picked are way to stiff, but I think they’ll be okay on the kick, because the beater hits a lot harder. Plus I won’t need to put padding on it to dampen the sound since the beater is some soft material anyways.

The other change in the design I’m making is to get some bolts with flat, threadless areas up at the top of them, about an inch worth. When the top board is pushed down it can catch the threads on it’s return, so that’s kinda iffy.

I also did some browsing today. See, I never actually did any poking around on the net before starting, I just got the idea and started building. It seems that DIY triggers aren’t that hard to find. Most are made of a piezo tansducers and practice pads. Example. I haven’t the slightest if that would work here. I think those are more of a range of current, as opposed to a strict on/off like a keyboard. I fully intend to go buy one after work tommorow and meter it to see if it can handle the job. That would make life much simpler. If not I can just make it into an acoustic guitar pickup.

Here are the required photo’s. The little white box is the home from the keyboard circuit board plus my little “breakout” board. I made that because I couldn’t solder directly onto the contacts, so all the connections are hot-glued and the breakout board is to reduce the amount of wiggling and tugging I do on the board to finish it up.

Back To The Software

November 8, 2006 » Geek

After some fantastic hardware work I’ve started yet another rewrite of the software for DK421. This time I’m rebuilding it to use more graphical options and let you load new clips without restarting the whole thing. I’ve been learning a bit in my Java class about all this GUI stuff, so I thought I’d apply it.

I’m still hoping someday I can add a save/load functionality to bring in a while sound set. Not the biggest deal at this point, but it would be a nice convenience. I’ve also gotten the first test drum pad cut and am going to buy the other pieces tomorrow. I might have a working pad by tomorrow evening, though my late classes might have something to say about that. I’m tempted to bring my controller to school and work on it between classes. Probably won’t though. Anyway, DK421 is in the early stages of version 0.03 now, I think it’s time to make it a better project page.

P.S. I’ve set the size for this project: 12 Controllers. So that comes out to 1 hi-hat and up to 9 other pads (cymbals, snares, whatever). More than enough for almost any drum kit. I think my first hardware version will be snare, hi-hat, kick, crash, ride. I’ll probably add toms later.