Monday, December 26, 2011

New location! New brake lights!

So a few months ago I bought this:

I found it for dirt cheap and it only needed a little bit of work, including a new speedometer and new horns. And some TLC. I thought I might be able to make some money by flipping it. Then I decided instead that I should move to Florida:

So I loaded it into the truck bed and put Sue on a trailer and drove 14 hours. And I think it put a little stress on the truck's springs:

It ended up making it down just fine, but it was a little worrisome. (Those will be getting replaced pretty soon.) But! About the same time as all of this, I designed and built a circuit that will hopefully connect to Sue's center brake light, so whenever the brakes are pressed the center light flashes eight times and then stays on until the brakes are un-depressed.

Currently Sue doesn't have a center brake light because I removed it to remove the back dashboard, so I could put some speakers in back there, and when I pulled the cover off the entire housing for the brake light disintegrated. So once I get a new center brake light built I will be able to attach this to it:

The only thing I couldn't quite figure out about it is that it seemed like it wouldn't flash exactly eight times every time at first. If I flipped the switch for it off and on without waiting a few seconds, it would behave erratically. This was fixed by putting a capacitor from the positive rail to the ground rail but I'm not sure exactly why this stabilized the behavior of the circuit. I have lots of ideas about why but there's no telling exactly why without an oscilloscope and some other things. More pictures in the future when Sue gets fixed up!

USB for the Truck

Well Verizon decided that their "unlimited" data plan is more "unlimited*" than truly unlimited, and they restricted my ability to tether my phone to my computer for the time being. At the same time I am moving to Florida so I wasn't about to have the internet folks come hook it up at my apartment in Tennessee right before leaving. ANY WAY even though I haven't had internet I've still been building neat things.

I had a GPS charger hooked up to a motorcycle (because the motorcycle doesn't have a speedometer that works) but it wasn't weatherproof. So the mini-USB port on the end got corroded and unusable and I cut it off. I decided I would use the business end of it to wire up a female USB port to the dashboard of my truck.

Here you can see part of the shell for the electronics that would normally plug into a cigarette lighter-type outlet, and the female USB port I am planning to wire it to.

These are the electronics that convert the 12V from the car battery down to the 5V needed for USB and other miscellaneous things like GPS units. The converters I've built in the past have used a regulator, which wastes a ton of energy. This unit is a buck converter which is much more efficient than a regulator.

All I really did at this point was solder in a fuse on the 12-V side (since the one the original equipment had was embedded in the plastic shell covering the electronics), solder the USB port up (making sure to solder the data wires together, as I learned in a previous post), wrap electrical tape around all of the sensitive parts (including the entire electronics module, it had exposed electrical parts that I wouldn't want rubbing on things inside the dashboard), and clip it in to the wiring for the CB radio.

I used JB weld on the inside of the piece of black trim to hold it in place. If you zoom in you can see some of my sloppy work with it. It is very strong though. The only problem is that I believe I clipped it too close (electrically) to the CB radio, and now if the truck is off for longer than 15 seconds or so the radio forgets what channel it was on and resets to channel 9. This is only a minor problem though, it may or may not be fixed in the future.

Any way, I can now charge anything by USB in the truck now! Cell phones, iPods, GPS units, anything that runs off of 5V. I suppose I only did this because I could, I have two 12-V cigarette lighters that I almost never use (not to mention the 120V AC outlet), so it's not like I'm pressed for numbers of outlets. Still neat though!