Tektronix OI1125, Instruction Manual

Page: 62 / 88

Performance Verification
50
OI1125 E/O Transmitter Instruction Manual
Modulator Optical Output Using an External Laser
Check the specifications of the modulator output by doing the following
procedures.
These procedures direct you to set up the equipment to display an eye pattern
using the external, tunable laser as the optical source. Use the eye pattern to
measure the parameters listed in Tables 19 through 21 in the Test Record.
Test Overview.
1. Connect the test circuit.
2. Set the BERT parameters.
3. Set up the tunable laser.
4. Set initial oscilloscope settings.
5. Preview the eye pattern.
6. Set the oscilloscope measurement parameters.
7. Perform an oscilloscope compensation and dark level compensation.
8. Take measurements.
Test Circuit.
Connect the equipment as shown in Figure 18 on page 51:
1. Beginning with the test setup from the previous test, disconnect the
attenuator from the BERT output, and connect the cable to the BERT.
2. Disconnect the optical cable from the internal laser out and the laser in
connectors on the transmitter. Connect the external tunable laser to the laser
in connector.
3. The equipment is now connected as shown in Figure 18 on page 51.
Eye Pattern Test Matrix