Well, I got her together, and working like a champ.
Everything here is running on 12V or a direct derivative of it (ie buck and/or boost) with the exception of the head unit.
One thing . . . Excuse the crappy rendering of the panorama; on the other hand, gotta love a Droid!
. . .
From top to bottom, left to right:
'Above' the top shelf: The tweets, providing most of the stereo 'dimension', with a small portable CD player (barely visible) in the center.
Top shelf: The two AIWA dual 4" mid/full range; they sound good by themselves, but really bring in the middle of the spectrum when added to everything else. They don't play around either; each box is capable of handling 125W. Seen 'em do it.
Middle shelf left: The infamous $500 charger, built completely from scratch, but I learned a lot of expensive lessons on this thing. Schematic is available on request just in case anyone wants it. It does what I built it to do, and will probably outlast me in terms of lifespan, but damn, it ought to! It cost me enough!
The red LED on the panel indicates that there is no AC input from the mains, as is evident by the power cord hanging just above the unit and to the left.
Middle shelf center: My implementation of Commanda's buck converter for solar (search "Commanda's Design" for details). The fan only runs when the toroid is chaotic, which seems to be when the MOSFET and Schottky give up their extra heat. Kinda a natural thing there, didn't have to do much to make it happen. The knob is for manually finding the panel's sweet spot, and there are two LEDs to the right of that. A flashing red indicates that the load side (battery) has become disconnected for whatever reason (blown fuse, etc), the obnoxious as I don't know what blue one indicates that the 5V regulator inside is operational. In the pic, the blue one was masked by several layers of tape to get rid of the starburst in the camera, hence it's wierd appearance.
Middle shelf right: GHurd's dump controller driving two IRFZ44N MOSFETs which drain up to 60W of surplus into six 10R 10W power resistors on the other side of the heatsink. The fan on the heatsink is connected via a Schottky and filter cap so as to run only when the dump load is active. Speed is proportional to power dissipated.
Lower shelf: A Technics 50x50 that I've had for aeons, and it still works as well as the day I got my hands on it from it's previous owner. The only thing ever wrong with it is that the FM receiver took a dive before I got it, but I didn't care, I don't really listen to radio that much at all anyway. $50 makes it one of the more expensive single units in the system. It's also the only piece of equipment that runs on 120VAC.
Inside the cabinet: An old 'Balance Technologies' laptop, whoever made that. Showed up at wally world briefly several years ago, and while I was at the PC shop fixing computers. Long story short, my boss bought a bunch of them, resold them at a margin, and my ex ended up buying one (before we knew where he got it from). Anyway, it works fairly well, the battery was always crap and doesn't work at all now, but it doesn't use much juice (compared to several others I have) and it has a DVD-ROM on it. Good enough to make the cut for the entertainment department!
Subwoofer: This one turns heads. It's a single 8 inch quad coil wired as 8 ohms (4x2R series), rated 150W, but is only dished a peak of 60W from a homemade amp I put together a few years ago. There's a thread floating around on here somewhere if someone is interested in how that went. I didn't actually build the amplifier, but I did put the power supply together completely from scratch. It's pretty efficient, considering, and if I had to do it again, I'd make a few adjustments to help with the lower power (ie idle) consumption. Not going to mess with the original, works well enough, and at the time, efficiency wasn't the most important thing anyway; it was for my car.
Battery box: Really all that is in here is just the collection of batteries, the main one that runs everything in the stack is the 8D, the others are there on a 'removable' basis, and this is just kinda their 'home'. I have a special charger adapter that repurposes the laptop's power supply (a boost converter) to charge almost anything and everything that fits in the 12V category. It is a little in disarray; I had a couple of items 'folded up' so that the doors would close while I was testing something and forgot to straighten them back out before taking the pic.
There you have it! A rather robust RE powered entertainment system!
I'll get the exact power requirements as soon as I get a chance, but at a reasonable volume level and just playing music from the Droid, it's somewhere in the 30W range. With the laptop in operation, this doubles and maybe a little more. Probably closer to 70W or so.
Collectively the panels that power this are
rated 60W, but I'm only getting between 40 and 50 out of them (depends on how low the battery is and if I do any 'hacks' to maximize the juice). Looks like panels are my next eyeball catcher!
It's always something!
Steve
