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From the no-updates department:

Craptastique! Me no bloggum long time!

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Christmas light project

There’s an unwritten rule where if you own a house you have to put up Christmas lights. There’s an unwritten rider on that rule where if you own a house and you’re a geek you have to spend lots of money and time on some really strange lighting project.

So this year’s plan is to have some Christmas lights controlled by computer. Picture the front of my house (OK, just play along, any house will do). Now imagine there’s floodlights on the ground, in front of the house, facing upwards towards the house. There’s three floodlights — one red, one green, one blue — in each of three groups. Nine floodlights total.

Still with me, here?

Now, all the red lights — there’s one red light in each of the three groups — are connected together and plug into one socket. All the green lights are on a separate socket. Same for blue.

Still playing along?

Good. That’s it. Next year, there’ll be dimming, too. Or I’ll go with something completely different. Stick around for an entire year of crazy, silly blogs and find out.

So how’s this light thing going? Let’s just say it’s been a learning experience. I started out on step one by putting together a pair of floodlights and relays, and connected the relays to the computer’s parallel port. That worked fine. The computer was able to turn the floodlights on and off. In step two, I was hoping to use the relays to make the lights dim, too, but alas, that’s not to be. My relays are zero-cross relays. Learning how my relays work was lesson number one.

OK, so with success in the turning-lights-on-and-off department, but failures in the dimming-lights department, I decide to go ahead with just lights on and off for now. Step three was the shopping-for-floodlights step. I walked away from the store with nine floodlights, nine little outdoor floodlight stands, and nine outdoor extension cords of various lengths to connect everything together.

Step four was to figure out how to enclose the relays and the wiring for outdoorsness. This involved buying lots of PVC enclosures and a couple of outlets.

Step five was to wire the enclosure up. This involved a couple of hours of cutting, stripping, drilling, screwing and glueing everything together. I even managed to stab myself in the hand with a screwdriver. If you sat around stripping and screwing for hours (and I don’t mean the fun kind!), you would too.

Step six was to wire the parallel port into the enclosure. I did that this morning. Here’s where lesson number two comes in. In my test setup, I used a little piece of phone wire to connect the relays to a parallel port. The final version uses about twenty feet of CAT5 cable. It turns out that a twenty foot length of CAT5 cable is not as good at power transmission as a small piece of phone wire is. There’s not enough juice in a parallel port to drive the relays at the other end of a 20 foot length of CAT5.

I’ll have to wait ’til tonight to try other options. Stay tuned.

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