TwinklePIC, part 4

Parts 1, 2, and 3

So, I had a circuit that worked and a program that made the LEDs twinkle nicely. But that is only part of the story: I also needed to dress it all up into a pleasing display. In truth, the soldering and programming were fun little exercises; industrial design is not something I would claim to have any talent with.

The Cosmic Nightlight that was the original inspiration for this project embedded its LEDs in a clear epoxy resin, into which was mixed streaks of color and children's glitter. The LEDs were arranged into the constellation Leo.

The results were very nice, and originally I planned to do the same. But in the end I decided to take a different approach. The epoxy was more labor-intensive than I wanted - and permanent! The author's nightlight was 3" x 6", dictated by the mold he used. I wanted something larger. In the end I decided on the following construction: I would embed the LEDs into a piece of 8" x 10" black acrylic, and set that into an ordinary picture frame. Much easier to just drill some holes!

I pondered what constellation, if any, to base the work on. I decided to make the Pleiades cluster:


It's beautiful, it's visible to the naked eye, it's a little off the beaten path, it has tons of history and legend associated with it, and it's the inspiration for the Subaru logo. Plus, I was using white LEDs for this project, many of which tend to have a slightly bluish tint to them, so a constellation filled with blue giants seemed appropriate.

Since my presentation was going to be pretty spare - no glitter or extraneous coloring - I at least wanted to go for fidelity. I could perhaps have found measurements of where each star is located in the sky, then transferred that to my 8 x 10 acrylic. I could have done it freehand. Instead, I went a much easier route, and made an 8 x 10 printout that I could tape to the acrylic, using the star locations as my drill locations. I found it much easier to first invert the image and print it black and white. It is well known that humans are better at picking out black spots on a white background than the other way 'round. This saved a lot of ink, too.


This then was the pattern I used to drill holes in the acrylic. I plugged the holes with the LEDs on wires that I showed in the previous post.

One thing I soon realized, however, was that these particular LEDs shone their light in a relatively narrow beam. In the dark, they were dazzling when viewed head-on, but didn't throw much light off-angle. There are things I could have done to combat this, including just getting different LEDs. But laziness won out, and I have just decided to live with it for now.

One thing I did to ameliorate the narrow-beam effect: I replaced the picture frame's original piece of clear plate glass with a piece of frosted glass. It doesn't do much for illuminating an entire room, but it does produce a nicer look from the side.

You'll notice that the stars in the cluster are not all the same brightness. I could have adjusted the program so that some of the stars were always brighter than their fellows. A better way would be to adjust it in hardware: each LED has a resistor in series with it. The resistor value has the effect of setting the maximum brightness: a greater resistance would result in a dimmer LED. The apparent magnitude of all the stars are well known. It would have been trivial to figure out what resistor values to use to get the relative brightnesses of the LEDs to match. Again, laziness won out, and I haven't gone to that length yet.

My intention originally had been to power this device from batteries. Based on testing I did with my prototype circuit, a fresh pair of AA alkalines would nicely light Brynna's room each night for just over a week. In that case, I planned on routing out a groove in the wood of the picture frame, and installing metal contacts at either end, so that I could indeed have the batteries as part of the frame. But then I got to thinking about all the batteries I'd be using over the years: it's unconscionable. Rechargeables were an option, but with shorter runtime. Plus, as the batteries drained, the LEDs would get dimmer.

Instead, I decided that the best long-term solution would be to power it from a high-efficiency AC/DC converter. A USB power adapter would do the trick nicely: they're easy to find, relatively inexpensive, can be really tiny, and can be extremely efficient. I'm presently using the adapter from the current generation of iPhone: it's >90% efficient, zero vampire current, and less than one inch cubed. The USB cord, and required proximity to an outlet, are a livable compromise.

You may recall that I also installed a mode-selecting switch, which would toggle the LEDs from twinkling to solid to off to twinkling again. This I planned to install on one corner of the picture frame. If I installed it on the front it would be easy to find, but a bit of an eyesore. Instead, I planned to install it on the back side of the frame, so that to activate the switch all one need do is push that corner of the frame as it hangs on the wall.

How does it look? You'll have to wait for the 6th and final installment. Before that, we'll revisit the electrical circuit, and how I transformed it into a printed circuit board.

Upgrades on Four Wheels

Northern New England, for those that don't know, is Subaru Country. There must be something appealing about how awesome all-wheel-drive is in the snow. Maybe it is the ability of Subarus to last to 200,000 miles that appeals to a Yankee's sense of thrift. Whatever the reason, there are a lot of Subarus around here.

So, when Hilary's car reached the end of the line a year ago by utterly failing New Hampshire inpsection, we had little difficulty in replacing a '94 Legacy Wagon that has 140,000 miles on it with a '95 Legacy Wagon that had 203,000 miles on it. This was largely a strategic move: at the time we were in process of buying our house, and didn't want to muddle our credit by applying for both a mortgage and an auto loan in the same breath. So, we sought a bridge car with a little life left in it, one that could take a place of Hilary's flagging station wagon at least through the winter. We paid a whopping $750 for it in a private sale, spent a little to fix it up and - wonder of wonders - managed to get over a year and 10,000 miles out of it.

We knew it was getting old by any number of measures. We could tell from the various noises that it was on questionable mechanical footing. Sure, it was always a struggle to find third gear. Sure we hardly put any money into fixing or maintaining it. But golly if it didn't start up every single time! We took it in for its annual inspection a while back and were told that they would pass it this year with some reservation, but assured us it wouldn't pass again next year. I guess 15 New England winters had finally gotten to it, and were beginning to cause some real structural integrity issues.

So, with tremendous gratitude, we drove that car to a Subaru dealership in the area and bought ourselves a new one. Well, not exactly "new" - it's a 2002 Subaru Outback wagon with 60,000+ miles on it. That's pretty low miles for a car of that age, and seems to be in great shape. It even has butt-warmers, something Hilary is quite pleased about with winter on the way. Here's hoping to another ten year, 100,000-mile relationship with Subaru!

Car Go Bye Bye

It is a sad event to say goodbye to an old friend..a trusty companion, a good steed. Yet, as we found out a while back, this chariot had, after 15 years and 140,000 miles, given out. We already had the replacement, all that was left was the disposition of Hilary's old car.


Because we bought her new car in a private sale, the old subaru had zero trade-in value. We could have perhaps tried to sell it ourselves, but with all the necessary fixes and its present lack of road-worthiness, we'd be lucky to get much of anything for it, and then only after a lot of legwork on our part. No, instead, we donated it to NHPR. They make it real easy - just an initial phone call to get some information (make, model, etc.), then a follow-up phone call from the auction house that would send a tow truck for it. We've been told that, should the car fetch more than $500 at auction, we'll get a sort of itemized donation receipt for tax purposes. Frankly, I'd be surprised if NHPR got that much for it, but we'll see.

Thankfully, they were able to do a pickup on Saturday morning, which was about the only time we'd be available. Though there was some difficulty when the truck arrived. The driver was all in a huff and a hurry and dismayed that, at 7:30 am, half an hour before the scheduled pickup window, we hadn't already fetched the (plateless) car and laid her out ready to go. Thankfully, Hilary was already on the way, and we'd already cleaned out most everything of use and moved it to her new wagon. The main thing to go was a set of snow tires, which ought to come useful if the new wagon lasts to winter.


Some fussing around with chains, some whirring of the winch, and there she was, laid up on the flatbed, and off around the corner with hardly time for a proper goodbye!

The Car Problem...Solved!

So, we left you, our dear readers, hanging, with the Moose Family temporarily reduced to a one-car family. How to get a new car? We didn't want to take out a car loan right before taking out a mortgage, or spend a bunch of our down payment either.

(This whole thing would have been much easier if it hadn't been raining, and raining, and raining, making a bike commute, even to the hospital, dangerous...)

But I can now present the new Moose Family auto:



"But Hilary," you may say, "that looks just like your old car!"

Indeed. We solved this problem in fine New England style—we met a guy at the Norwich farmers' market! He was parked next to us, Alex struck up a conversation with him, and it turned out that he was selling his car. For less than $1000. We realized that this was the perfect solution, an inexpensive bridge vehicle that we hope will get us over the mortgage hump. It is a 1995 Subaru station wagon, making it a whole year younger than the almost-identical car it is replacing. Though I suppose "new" may be a little bit of a stretch. Especially since it has 203,000 miles on it. However, it does have the added benefits of having a manual transmission and no automatic seatbelts, addressing my biggest complaints about my old car!

We bought it contingent on it passing the New Hampshire inspection, or requiring only minimal work to do so. Two weekends ago we drove up to Vermont, picked the car up, took it across the border to New Hampshire, and had it inspected. It did need a little work (a new CV and outboard axle assembly), which it had this past week. Now it is all inspected and registered. Welcome to the family, Subaru Two!

Bye, Bye Car...

So, apparently my car took us a little too literally when we asked it to pretty-please just get us back to New Hampshire. Yesterday I took it in for its state inspection (and a few other things as well), and then we got a phone call that told us it would require a tremendous, expensive amount of work just to pass the inspection.

My car is a 1994 Subaru wagon with almost 140,000 miles on it. We aren't going to spend thousands of dollars to fix it.

And so, in the midst of this rainy weather, we are a one car family and on the lookout for a much-less-used Subaru wagon! Luckily we are in northern New England, the Subaru heartland, and finding one shouldn't actually be all this difficult. I think they all might come with a complementary Obama sticker, too.

(Yes, I would love to have a hybrid, but we need a car with more cargo space than a Prius, Accord, or Insight.)

Commute

I've finished my second week at my new job. There's not much that I can say about it in an open setting such as this blog. So, instead, I'll talk about my commute.

My last job, in Rochester, was delightfully close by. So close, in fact, that I had a mere 17 minute walking commute from front door to my desk. That was quite nice. In fact, I was so junior at the company that, even if I wanted to drive to work, it would have done me little good: I would have had to drive away from my job, park the car, then take a shuttle back in. Yup, walking was a great way to go - even in minus 20 weather.

Now, however, I live in Concord and work in Manchester. So, I not only have a 20+ minute commute, but it's a driving commute. I'm sure many of my more urban friends will laugh at that, but it's a big deal to me.

I don't begrudge the time in the car all that much. Traffic isn't too bad, it's almost entirely a straight shot on the highway, and I listen to NPR going to and from. I do worry about the miles, though. My Jetta manages 30+ mpg on the highway, which I consider pretty good, but 40 miles of daily driving is a hit to the pocket and to the carbon footprint no matter what I'm driving. The gas cost is about $3.50 with current prices. If I figure in insurance, depreciation, and everything else that goes into the IRS' $0.55/mile reimbursement rate, it becomes an extra $20/day compared to my old job. There's also a $1 toll each way, which is easy to forget when using the EZPass.

I'd be stoked to get a car with better mileage, but it is tough to justify replacing perfectly good automobile just to reduce my gas consumption by only 25-33%. Taking out a car loan right now would be a poor tactical move in our quest to securing our next mortgage. Besides, if we're replacing any car in the near future, it's probably going to be Hilary's, uhhh, hale Subaru wagon - 15 years old and 140,000 miles.

What is the solution to this problem of commuting? I'm not sure. It is almost certainly too far to bike. Even in training it would be an hour each way - time that I can ill afford. There may be carpooling or shuttle buses available, if I can make that work with my work (and Brynna's daycare) schedule. Moving closer is possible, but it is probably more important for Hilary to remain close to the hospital.

Perhaps I'll just get used to it, like most everyone else does. I hope, even if I can accept it, I don't ever forget it.

And we're off!

The Subaru is utterly packed. And we are getting onto I-90 for the long drive east to Rochester NY. Maybe we will blog state by state!