HP 83480A

The Digital Communications
Analysis Menus
Measure Eye Menu
NOTE
The dark cal routine requires that the dark signal level be on screen. If this level (for example,the
signal level when a laser is turned o) is not seen on the screen, the dark cal will fail.
Key Path 4
Shift
54
Meas eye
5
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
Extinction ratio...
NNNNNNNNNNNNNNNNNNNNNNNNNN
Dark cal
Extinction ratio
can be
displayed in
one
of
three
formats:
dB
%
ratio
The
desired
format
is
selected
in
the
Extinction
Ratio
menu.
K
ey
Path
4
Shift
5
4
Meas
ey
e
5
N
N
NN
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
NN
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
NN
N
N
N
N
N
Extinction
ratio...
N
N
NN
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
Format
ratio
,
decibel
,
or
%
The
ratio
format
calculates
extinction
ratio
as:
r
atio
=
V
top
0
V
dar
k
V
base
0
V
dar
k
E
xtinction r
atio per
cent =
100

V
base
0 V
dar
k
V
top
0 V
dark

E xtinction r atio dB =10 log

V
top
0 V
dark
V
base
0 V
dark

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