BNC 130 - Manual (Page 29)

29
MAINTENANCE AND CALIBRATION
CW and External Modulation Calibration
Using the patch cord, connect LIGHT OUT to the 6100 Optical Power Meter. Set the 6100 for Average
power measurement and the 0 dBm range.
Set the 6040 Mode to CW and the CW level to 1.000 mW If necessary, adjust R11 (Schematic 133-31,
sheet 1) to obtain a reading of 1.000 mW ±10 µW on the 6100. Set the CW level for 100 µW and verify
the output to be within 10 µW.
Set the 6040 Mode to External Modulation (with no input connected to EXT MOD) and set the External
Modulation level for 1.000 mW. Verify an output of 1.000 mW ±10 µW. Set the External Modulation level
for 100 µW and verify the output to be within 10 µW.
Pulse Baseline Calibration
Set the 6040 Mode to Pulse, and the Trigger to Single Cycle.
A) Set the 6040 Baseline level to 1.000 mW. Adjust R83 (Schematic 133-31. sheet 3)
to obtain a reading of 1 .000 mW ±20 µW on the 6100.
B)
Set the Baseline level to 100 µW. Adjust R22 as necessary to obtain 0.100 mW
±20 µW.
Repeat steps A) and B) until both readings are within 20 µW of their stated values.
Pulse Peak Calibration
A) Set the Baseline level to 0.000 mW, Set the Trigger to External Drive with a
threshold of -50 mV. Adjust R58 (Schematic 155-31, sheet 3) for an output of
1.000 mW ±20µW.
B) Set the Baseline level to 100 µW. Adjust R19 to obtain an output of 1 .000 mW
±20 µW.
Repeat steps A) and B) until both readings are within 20 µW of their stated values.
Note: The following sections require high bandwidth paths; any improperly cabled terminated paths will
yield incorrect results.