Example: Identifying The Modulation Frequency - HP E5970A User Manual

is not high enough for the power meter to identify the modulation. This will
I
happen
at
power levels below -45dBm at 850nm, and at power levels below
-50dBm at 1300nm, 1310nm and 1550nm.
Example: Identifying the Modulation Frequency
In this example, we will identify on the power meter the modulating frequency
being used by the source.
The example uses the following equipment:
a The HP E5970A Optical Power Meter with a HP 81005AA HMS-10 Adapter,
rn A HP E5972A LED Source with a HP 81005AA HMS-10 Adapter,
A HP 81101AC Diamond HMS-10MP to HMS-fOMP Patchcord.
1. Set up the equipment as shown in the diagram:
Set Up for Power and Loss Measurement Example
2. Switch on both the instruments.
3. Press on the source. Note that the modulation indicator on the power
meter shows 270Hz (after a slight delay).
4. Press
on the source. Note that the modulation indicator on the power
meter shows ]kHz (after a slight delay).
5. Press on the source. Note that the modulation indicator on the power
meter shows 2kHz (after a slight delay).
2-2 Identifying Modulated Light