Agilent Technologies J-BERT N4903B, User Manual, Page: 132 / 572

Adjust Output Levels (optional)
Data, Aux Data, Clock and Trigger/Ref Clock offset and voltage levels can be
adjusted. This is typically done when you want to tune your BER measurement or
stress the device.
You can use the knobs on the Serial BERT's front panel to fine-tune the data and
clock amplitudes and offsets. If you want to set a specific value, you can use the
numeric keyboard.
To enter specific values for the outputs from the keyboard:
1 From the
PG Setup
menu, press
PG Data Setup
to modify Data and Aux Data,
and
PG Clock/Trig Setup
to modify Clock and Trigger.
2
Click into the field you want to change.
3
Enter the desired voltage using the numeric keyboard or the respective front
panel knob (only for Data and Clock).
N O T E
If the termination voltage is wrongly adjusted or the output ports are not connected,
an internal protection circuit automatically sets the output voltage levels to safe
levels. Connect the output ports or change the termination voltage before adjusting
the output levels.
See “Understanding the Output Level Parameters” on page 126 for information
about how the Serial BERT works with output level parameters.
Controlling the De-Emphasis Signal Converter
After the
De-Emphasis
function has been enabled using the
External Instrument
(s) - Config
menu, the following parameters are visible in PG Data Output screen.
Controlling the N4916A De-Emphasis Signal Converter
For N4916A, you have de-emphasis amplitude (post–cursor) and the corresponding
unit.
4
Setting up the Pattern Generator
132 Agilent J-BERT N4903B High-Performance Serial BERT