HP 54750A, Руководство пользователя, Страница: 181 / 478

The Digital Communications
Analysis Menus
Time Base Menu
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Units
This function is only available with the HP 83480A, or if the HP 83480K
option is installed in an HP 54750A.
The Units function lets you set the instrument timebase to basic time units
or to bit period units . Bit period units provide an easy and intuitive way to
display digital communication signals . Instead of having to compute the time
interval required to display two bits or eyes , you can simply set the scale to
two bits . Refer to the Scale softkey , later in this chapter .
K ey Path 4 Time Base 5
N
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Units time or bit period
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Bit Rate
This function is only available with the HP 83480A, or if the HP 83480K
option is installed in an HP 54750A.
Bit rate allows the time base to be congured for a variety of standard optical
and electrical telecommunications rates .
In the Bit Rate mode , the knob and arrow keys scroll between standard rates
for digital communications signals . T o select a non-standard rate , enter the
rate from the numeric keypad. T o enter values in Mb/s , enter the number
followed by 4
Eex
5 4
6
5 . T o enter values in Gb/s , enter the number followed by
4 Eex 5 4 9 5 .
K ey Path 4 Time Base 5
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Bit rate
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