1. Project GabE ECE 135 – Spring 2005 Week 9
Rahmin Sarabi
Omar Al-Jadda
Patrick Crosby
Adam Durity

2. Gantt Chart

3. Progress Report Posted completed Midterm report to website
Tested two Tx’s
Tested and verified functioning Rx

4. Tx Testing First test yielded non-working circuit
Laser driver not powered
PROBLEM: ground pins from power supply not grounded on board
SOLUTION: soldered a connection to ground plane
FRONT
BACK

5. Tx Testing Laser Driver now powered successfully
Signal trace performed to VCSEL
INPUT
OUTPUT from Laser Driver

6. Tx Testing We will set to meet modulation current requirements
MODSET potentiometer closes and opens eye
We will set to meet modulation current requirements
Tx output - high resistance
Tx output - low resistance

7. Tx Testing VCSEL did not lase on both boards
Connected to pattern generator’s optical receiver
Rx LOS indicator came on - VCSEL off
Dr. Brooke’s approach to determine appropriate POT settings

8. Rx Testing Tested with input from pattern generator
Very good eye pattern

9. Upcoming Week Revise design and schematic for second board run
Address lasing failure
Build second Rx
Revise design and schematic for second board run
Order second board