Agilent Technologies 71501D, User Manual

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Getting Started
Steps for Setting Up Eye-Diagram Analysis
These softkeys can also be used to specify an optical-to-electrical responsivity
conversion between the source and input channels. As a result, the display
shows optical units referenced to the input of the optical-to-electrical con-
verter. Channel and marker readouts change to watts/div. Also, the CH1 EXT
ATTEN softkey changes to read CH1 RSPVTY (responsivity).
Autoranging
The Trg,Cal menu’s autorng ON OFF softkey turns on or off autoranging.
When autoranging is activated, the eye-diagram analyzer automatically selects
the appropriate hardware gain and offset to maximize the signal at the analog-
to-digital converter, regardless of the input signal’s amplitude.
Selecting the 10 MHz reference on Instrument Preset
Use the Trg,Cal menu’s IP REF softkey to select the source of the 10 MHz ref-
erence on an INSTR PRESET. Choices are internal, external, or auto. With
auto, the eye-diagram automatically selects an external reference if it is
present at the 70820A’s rear-panel connector. Otherwise, the module’s inter-
nal reference is selected.
Redefining the INSTR PRESET key
The Trg,Cal menu’s DEFINE USER IP softkey redefines the settings invoked
by the INSTR PRESET key. Redefining the instrument preset can save valu-
able time when configuring for measurements.