I've never had so much interest in a console than I have with the Nintendo Wii. I must say, Nintendo shocked me back when they announced details of their new "Revolution". At the time, I was an Xbox addict (especially with Halo 2 online) and couldn't see what Nintendo could possibly offer me. I had written off Nintendo as a kid-centric company, not something for serious gamers. Then I saw the Revolution video showcasing what looked like a white TV remote control. At first glance, I thought Nintendo had lost their minds (how could someone play anything worth while with that thing?). It wasn't until they showed how people could use the remote (along with the optional nunchuck) when it really clicked. Whoa! Motion and direction-sensitive controlled gaming? I could easily see everyone wanting a console like this. Talk about innovation. But, how well will it really work? I was willing to wait 7 hours in line on launch day to find out.

First impressions

Upon opening the box, the Wii hardware stuck me as being elegant. Simply plug in the console and place the sensor bar and you have everything you need for a radical new way of gaming. So, I fired up my big HDTV and the console, sat back, and started moving my virtual hand across the Wii Menu. The result? The cursor was incredibly jittery. None of the demo videos I saw looked like that, so, I figured it must either be a bad setting or something with my environment. The sensitivity setting didn't help, but, what I did notice that getting up closer to the TV did help. In fact, it worked best when I was about 4' away from the sensor bar. My couch is 11' away from the TV, so, this was obviously going to be a problem (for me and every person that plays a Wii on a large TV).

My next step was to move the sensor bar closer to me. My only option was the coffee table. But, it stands pretty low. The cursor was smoother this way, but, I was aiming below my TV for results (not to mention I was straining my arm to do so). The sensor bar really needs to right below (or above) the TV. To gain the correct line of sight between the remote and the bar so that aiming felt right, I had to put the bar on top of a big stack of books. This was ridiculous and not something I wanted to do every time I play my Wii.

Not really a sensor bar

It wasn't long before information about the sensor bar started showing up online. The fact is, the sensor bar isn't really a sensor at all -- it's an emitter. All the smarts are in the Wii remote. People had success with creating their own sensor bars. Many infrared (IR) sources would work (including candles!). Various wireless sensor bar configurations started popping up as well (you can even buy them now). This was great news as it opened possibilities for solving my dilemma.

Wireless versions of the sensor bar isn't a good solution

I wasn't interested in either creating or buying one of the wireless sensor bar solutions coming online. As I mention before, the bar needs to be positioned in such a way that the remote targets the screen correctly. What I really wanted was IR emitters that were on my TV's frame. With that, I came up with some goals.

Project goals

1. Allow Wii gaming from a distance of 11' or more
2. Build high-quality, bright and stable IR sources for best detection by the Wii remote
3. Position IR emitters close to screen for proper and natural targeting
4. Emitters should be small and as discrete as possible
5. Emitters should move with the TV as it swivels
6. Use easily attainable parts
7. Don't require batteries
8. Don't spend a lot of money

Complete success

Below is a picture of my 40" HDTV with my custom "sensor" bar affixed to the top of the TV's frame. I'm thrilled with the results! The on-screen cursor is incredibly stable. The cursor never jitters. It's even more stable than with the standard Wii sensor bar at close range (which was still jumpy for me when pointing at the far corners of the screen).

Notice the distance between the emitters. The standard Wii sensor bar has emitters positioned 7.5" apart. As I mentioned before, I was getting best results at 4'. Given that I sit 11' from my screen, using simple trigonometry, I computed that the emitters must be spaced a litter more than 20" apart at my distance.

Each emitter uses 9 IR LEDs and is housed in a small 1" square project box. They are slightly tilted downwards to best hit my couch.

Each emitter uses 9 IR LEDs and each strand of 3 uses a special LED driver to guarantee constant and optimal brightness (i.e. an always constant current of 20mA through every LED). The emitters are driven using a standard 9V power adapter.  The hardware was ordered online from Mouser and some was bought locally from Radio Shack. Total cost was around $25.

Hey Nintendo -- people want to play the Wii on large HDTVs

I can understand Nintendo providing an out-of-box configuration that works for the lowest common denominator (i.e. people running on smaller standard definition TVs). It's good that Nintendo does appear to care about HDTV by selling component cables (by the way, a must if you are gaming on an HDTV) and supporting 480p widescreen modes. But, they absolutely need to offer an alternative sensor bar for owners of large TVs.

A simple variation of the existing sensor bar would do. My advice to Nintendo is: make a sensor bar that is brighter and its width adjustable to enable gaming at greater distances. They'd make a lot of gamers happy.

Parts List

I'm including the parts list of the critical components that make up the emitters. The wire, 9V DC power source, on-off toggle, and power indicator light are common parts that can be found at places like Radio Shack.

• Supertex 20mA Constant Current LED Driver (http://www.supertex.com/pdf/datasheets/CL2.pdf) (CL2N3-G, MouserPN: 689-CL2N3-G, $.44/ea) : Used one per series of IR LEDs with a 9V source. 3 total per emitter.
• Fairchild 940nm 27mW/sr Infrared LED (http://www.fairchildsemi.com/ds/QE/QED233.pdf) (QED234, MouserPN: 512-QED234, $.23/ea): Used 3 per series. 9 total per emitter.
• Bud 1"x1"x.75" Potting Boxes (http://www.budind.com/pdf/hb1558.pdf) (Box: PB-1577, MouserPN: 563-PB-1577, $.59/ea) (Cover: PBC-1577-C, MouserPN: 563-PBC-1577-C, $.35/ea): Used one box per emitter plus another to house the power connector.

The 20mA LED drivers used must have at least a 5V drop. Given that each LED drops 1.2V at 20mA. Three LEDs in series makes 3.6V which leaves 5.4V when a 9V power source is used. There are 6 LED "strands" total (3 per emitter) each drawing 20mA for a total of 120mA draw from the power source. Make sure your power source can handle that load (for example, the one I'm using from Radio Shack is rated for up to 300mA and I chose to use an M type connector).

I wanted to keep the emitters as small as possible. As you can see from the pictures, there isn't a lot of room to house all these components. Be aware that precision soldering and drilling is required if a project box this small is used.