Hardware Specs

The ThinkStick's small size [3.5" x 0.9375" x 0.4375"] allows it to be plugged into those tight locations such as the one on my laptop shown below. (Figure 2) Also notice the blue LED that flashes during data transmission.

Figure 2: Small Size Allows for Tight Locations

One of the first things I like to do when I get new devices is to take them apart and try to find out as much information as I can about the device. Looking inside the ThinkStick we can see that it was originally manufactured for Wayne-Dalton. (Figure 3)

Figure 3: Manufactured for Wayne-Dalton

The spiral circuitry at the back of the board is actually a planar antenna that has been optimized for distance and performance. It's obvious that size is an issue when developing antennas for these types of devices. An antenna tuned for Z-Wave's US frequency (908.42Mhz) should be at least 1/4 wavelength (3.091") and optimally, 1/2 wavelength (6.1821") long.

By using the old handy-dandy string method, I measured the ThinkStick's antenna to be slightly longer than 6", putting it just over a half wavelength. Antenna theory is actually much more complex than its length so don't let these number fool you. There are probably much more effecient antenna designs, but this one is a good start. I'm almost tempted to hack one of these sticks to include an SMA connector for easily adding and removing an external antenna. (Figure 4)

Figure 4: SMA Connector on Antenna

The main controller is a Silabs C8051F326 (Figure 5), which is a system-on-a-chip microcontroller that includes a UART (Universal Asynchronous Receiver-Transmitter), timers, and ports. The microprocessor has 16KB of ISP (In System Programming) Flash that holds the firmware.

Figure 5: SILABS C8051F326

Tags: ControlThink, Home Control, Z-wave,

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