PCB36-TU1

Overview
Teensy USB 2.0 breakout board with tilt sensor, IR transmitter, IR receiver and 2 LEDs.

TU1 v1 Assembly

 * TESTED: IR Transmitter would be blocked by PCB snap-in holders if mounted top-side. If mounted bottom-side, it will face the wrong way. An interesting way to verify that IR transmitter is working is with the camera from a mobile phone. The cheaper cameras are better at detecting IR. Specifically, the iPhone 4s low-res camera shows IR, while the hi-res camera doesn't. Next revision should permit bottom-side mount with PCB pin reversal.
 * FAIL: IR Receiver is blocked by PCB snap-in holders if mounted top-side. If mounted bottom-side, it will face the wrong way. Two attempts to solder IR receiver failed and destroyed devices. These devices are VERY sensitive and must be soldered with <350C for <3 seconds. That's really tough to do with high temp lead-free solder. Might work with low-temp solder paste and soldering iron set to 300C. Next revision should permit bottom-side mount with PCB pin reversal.
 * 5V/VIN pin header holes can take 2-pin right angle header mounted bottom-side. If you do so, the pin headers will slightly bend the bottom of C1U1 cases. Next revision should just replace the pin header with a diode
 * TESTED: Teensy USB 2.0 should be mounted upside-down on the top side of PCB36-TU1 to fit into C1U1 case. Bottom-side mount is also theoretically possible, although the 5V trace cannot be cut once the Teensy board is soldered in place.
 * TESTED: Use female pin headers for backplane. This is a powered board and the female pin headers will reduce danger of short circuits. C4 cases require shorter pin headers.
 * TESTED: The Teensy reset button is accessible via a hole in PCB36-TU1.
 * TESTED: Tilt sensor must be mounted top-side. It won't work upside down.
 * TESTED: Left LED
 * TESTED: Right LED
 * TU1 IRTest program