Agilent Technologies 11982A, Operation And Service Manual

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4-2
Verification and Service Information
Performing a Verification Check of the Agilent 11982A
Performing a Verification Check of the
Agilent 11982A
To verify the dc responsivity and functionality of the Agilent 11982A, use the
following procedure. Remember that the fiber-optic connections must be
clean.
1 Connect a laser with a wavelength of 1300 or 1550 nm (approximate) to an
optical power meter, and measure the output power of the laser.
2 Connect the RF OUTPUT of the Agilent 11982A lightwave converter to a 50
Ω
load
in parallel with a voltmeter (for example, an Agilent 3456A digital voltmeter).
3 Using the dc volts setting, measure the output voltage across the 50
Ω
load from
the Agilent 11982A without the laser connected to its input. This voltage
represents the output offset voltage and it should be within the specifications
in
Table 1-1 on page 1-6 .
4 Connect the laser to the OPTICAL INPUT of the Agilent 11982A lightwave
converter.
5 Using the dc volts setting, measure the output voltage across the 50
Ω
load from
the Agilent 11982A with the laser connected to its input.
6 Subtract the result of Step 3 from Step 5 .
7 Compute the dc responsivity for the Agilent 11982A by dividing the voltage
from
Step 6 by the optical power.
Compare this to the value provided on the Agilent 11982A Calibration Chart
for your unit. It should be within the tolerance specified in
Table 1-1 on
page 1-6 .
Note
If necessary, convert the scale of the voltage or watts so that the units are comparable.
For example, divide
µ
V by
µ
W, not V by
µ
W.