Yesterday, I ordered the components for 100+ kits — chips, meters, resistors, capacitors, and all that good stuff. The circuit boards were ordered back on Wednesday. I also ordered shipping boxes and padding. All the parts should arrive by the end of the week (December 5). Once I get the documentation and Web site updated a bit, I think we’ll open for kit pre-ordering around the middle of this week (December 3, perhaps?).

Today, I worked on the documentation. All the photos and diagrams need to be updated because the design has changed dramatically to accommodate the Atmel chip. I’ve replaced most of the diagrams already. Tomorrow, if the weather is nice or I can find some decent light, I’ll re-photograph the assembly process and drop those photos into the documentation too. There will also be a couple of extra steps, as the Atmel ATmega168 microcontroller requires a few extra components that the TI microcontroller didn’t.

I also worked today on improving the timekeeping accuracy of the clock. The capacitors that hook up to the quartz watch crystal have a small effect on the speed of the clock. My tests show the clock running a bit fast (about one second a day), although it’s well within the tolerance I should expect from the crystal, and about as accurate as your average wristwatch or wall clock. I was just thinking I could make it a bit better. In any case, there’s the strong possibility I’ll hack the Chronulator to connect to an atomic clock receiver or GPS.

I enhanced the Chronulator serial command set to permit control not only of meter needles, but also the brightness of the optional LED backlight behind each meter. That should make hooking your Chronulator to a computer just a bit more fun…

I don’t think I ever mentioned — there’s LOTS of pictures of Chronulator projects on Flickr! The craftsmanship just amazes me…

So here it is, Chronulator 2.0 number 1, photographed on the ShareBrained trademark kitchen tablecloth. It went together well, with just a couple of tweaks.

First, I forgot/neglected to connect power between the ISP port and the AVR chip. That’s no big deal for the 95% of people who don’t need to load their own bootloader. But it should work, so I’ll make it work by revising the circuit board.

Second, the circuit board holes on the quartz crystal were too close together. Therefore, there was no room for the solder mask treatment between the solder pads. And that made it hard NOT to create a solder bridge between the two pads, which would make the Chronulator not work. So I’m going to change the board to put some more space between the pads — enough to get a thread of solder mask in there…

I made these changes and will submit the *new* final design for manufacture tomorrow. I’m going to grit my teeth and pay for one-week turnaround. It adds about $1 to the cost of the kit, but will allow me to ship kits a week earlier (the plan now is to ship the first round of orders on December 8th). People love to give (and get!) Chronulators as gifts, so the sooner I can get them on sale, the better!

OK, with the details out of the way, I want to explain a couple of new things about the design:

First, the Chronulator 2.0 now uses the Atmel ATmega168, the same chip in the popular Arduino device. I’ve also included a port for an add-on USB-to-serial adapter (the SparkFun FTDI basic breakout board), through which you can program, control, and hack your Chronulator using the Arduino software. You can also power the Chronulator from the USB port, if you want to use your Chronulator with your computer.

Notice the lights on the meters? I’ve put places on the board for you to add high-power LEDs you can use to illuminate your meters. My experiments thus far making transparent meter labels have been not-so-successful, but I’m hoping my talented and creative customers can come up with some clever solution.

There are also spare pins you can connect to on the board. You can use these extra pins to control additional LEDs, another meter (for a “seconds” hand), or hook up to external devices like an atomic clock receiver module, GPS, various analog signals… Who knows? I’ll be posting the results of some of my hacking experiments. I hope you’ll do the same as you experiment with YOUR Chronulator!

I just received notice from Advanced Circuits that the Chronulator 2.0 prototype boards have shipped and will arrive tomorrow afternoon! The Digi-Key parts for the final prototype arrived today. So tomorrow evening, I’ll solder up a board or two and try ‘em out. If they work fine, I’ll put in the big orders with Digi-Key and Advanced Circuits. It’ll be about two weeks before we can actually ship kits. In the meantime, I’ll open up the store for advance sales.

Chronulator 2.0 development is proceeding, albeit more slowly than I planned. Here’s what it looks like right now:

Chronulator 2.0 Circuit Prototype

Over the last few weeks, I’ve gotten to know the Arduino development kit. With it, I’ve prototyped new Chronulator software, which is working at least as well as the old version.

I also spent too much time trying to figure out how to hook up an atomic clock receiver, to no avail. I’ll probably offer it as an optional add-on board, since the technical challenges are too great in making everything work with a single chip.

This week, I’m moving on to designing the circuit board. My goal is to make the board easy to program using the Arduino tools. You’ll need an inexpensive add-on USB-to-serial board from SparkFun. It’ll be much easier to tweak than the old Chronulator, which required complex, Windows-only development tools. And, being a ShareBrained project, all the Arduino source code will be freely available.

Once the board design is complete (November 2), I’ll have some prototype boards manufactured. I’ll solder them up and test them (November 9). If everything looks good, I’ll make any last-minute tweaks and send the design off to production.

While the boards are in production, I’ll work on the instructions and get all the other parts ordered. Once the production boards are back, I’ll test a few and then start building an advance batch of kits (November 23).

We should be ready to sell kits on November 24! Stay tuned for more updates…

Life and work are interfering with progress on the next ShareBrained kit. But rest assured, we have some good stuff coming in the next couple of months (meaning, “the summer of 2008″).

UPDATE: Texas Instruments has a neat little video on powering their MSP430 microcontroller from fruits and martinis! The Chronulator uses the same chip, although the meters draw substantially more current — you might need something bigger than a couple of grapes…

I want to try powering a Chronulator from some alternate power sources. Batteries and AC adapters are so boring.

The Chronulator requires 2.0 to 3.6 volts (V) and about 100 microamps (uA). That’s a miniscule amount of power. So this should be easy. I’m thinking a potato battery, and a small (just a few square inches) solar cell.

For the potato battery, I’ll likely need three or four “batteries” in series to get enough voltage. There should be plenty of current.

Since we can’t count on the sun for power at night, the solar cell solution will use a super-capacitor. The super-cap will charge up with excess power during the day, and release it at night. I bought a super-cap from All Electronics a while back. Maybe I’ll grab a RadioShack solar cell and see how this works in practice. I’m concerned that the super-cap might bleed down too quickly at night… But if this works, it’d be super-simple — no charging circuit necessary!

Gareth Branwyn (of Street Tech and the MAKE Blog) posted a review of The Chronulator kit to the Federated Media Holiday Gadget Guide. Thanks Gareth!

We’ve sold several dozen Chronulators so far, but have yet to receive any pictures! So if you’ve got a finished Chronulator you’re proud of, please send us pictures at info@sharebrained.com. We’re really anxious to see what you’ve done with your Chronulator!