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Model 2520 User’s Manual Laser Diode Testing 4-5
3. Press DETECTOR 2 V
B
to select the photodiode #2 source.
4. Again, using either the EDIT or numeric entry keys, set the bias source value to the
desired value.
Step 5: Configure math functions.
Set up your math functions as desired. For example, these steps will set up the unit for
laser diode power and detector 1 MX + B math:
1. Press CONFIG then MATH.
2. Select CHANNEL1, then press ENTER.
3. Select P for power, then press ENTER.
4. Press CONFIG then MATH.
5. Choose CHANNEL2, then press ENTER.
6. At the subsequent prompts, set the MX + B parameters (M, B, and units) to the
desired values.
Step 6: Turn source outputs on and trigger readings.
Turn all three source outputs on by pressing the ON/OFF OUTPUT key. The blue OUT-
PUT indicator on the mainframe and the testhead POWER ON indicators will turn on to
indicate the outputs are on. Press the TRIG key to trigger readings.
NOTE
Interlocks must be enabled before outputs can be turned on. See Section 2 .
Step 7: Observe readings on the display.
Observe the measurement readings on the display. For this example, the unit will display
laser diode power, detector 1 MX + B math, and detector 2 current on the lower line.
Step 8: Turn source outputs off.
When finished making measurements, turn all three source outputs off by pressing the
ON/OFF OUTPUT key. The blue OUTPUT and POWER ON indicator lights will turn off.
Remote laser diode testing
Laser diode test procedures can also be performed via remote by sending appropriate com-
mands in the right sequence. The following paragraphs summarize the commands and give
a simple programming example.
Laser diode test commands
Table 4-2 summarizes commands used for basic laser diode testing, including those for the
two photodiode detectors. See Section 14 for more information on using these and other
commands for laser diode testing.