Agilent Technologies Agilent 86120C manual Measurement rate

Making Measurements

Changing the Units and Measurement Rate

4Press WL and select one of the following units. Then, press RETURN to complete your selection:

•NM for nanometers

•THZ for Tera Hertz

•CM –1for wave number

5Press POWER and select one of the following units:

•DBM for decibels relative to a milliwatt

•MW for milliwatts

•UW for microwatts

Measurement rate

Under normal operation, the Agilent 86120C makes a measurement and displays the results about once every second. It is in this normal update mode that maximum accuracy and wavelength resolution are achieved. However, should a faster update be desired, for example when real- time feedback is required to tune a laser to its designated channel, the Agilent 86120C can be set to update approximately two times per second. This reduces both wavelength resolution and accu- racy but can be beneficial in some applications.

The instrument resolution in NORMAL update mode is 7 GHz (0.06 nm at 1550 nm). This resolution is useful when measuring closely spaced laser lines carrying data at up to 5 Gb/s rates.

The instrument resolution in FAST update mode is 14 GHz (0.12 nm at 1550 nm). This resolution is useful when measuring laser lines carry- ing data at up to 10 Gb/s rates.

NOTE

When measuring laser lines carrying data at 10 Gb/s in NORMAL update mode, the instrument resolution is less than the modulation bandwidth of the laser lines. In this case, the displayed power of the laser lines will be less than the actual power by approximately 1 dB. This power offset can be calculated by comparing the displayed power to that measured by a power meter. Then, the power offset can be entered, by pressing Setup, MORE, CAL, PWR OFS, to display the correct power.

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