HP 83480A User Manual

The Digital Communications
Analysis Menus
Mask Test Menu
NOTE
For proper operation, the channel external scale must be set to the total attenuation in the path. For
example, when using the HP 11852B in conjunction with a 10 dB attenuator, set the channel external
scale to 15.7 dB.To set external scale, select Channel, External Scale, and enter the appropriate
attenuation value.
Data
Rate
Z
ero
Level
V
oltage
One
Level
V
oltage
Recommended
Pad
V
alue
1
2.048
Mb/s
0
V
2.37
V
10
dB
8.448
Mb/s
0
V
2.37
V
10
dB
34.368
Mb/s
0
V
1.00
V
6
dB
139.000
Mb/s 0
0.5
V
+0.5
V
6
dB
1
In
addition
to
5.7
dB
loss
due
to
75-50
ohm
minimum
loss
pad
User-dened
masks
The
Mask
T
est
menu
also
contains
a
mask
editing
feature
that
allows
you
to
create
your
own
masks
. These
masks may
be
created
using
one
of
two
methods:
by
using
the
Edit
Mask menu
to create
a
new
or
modify
an
existing
mask,
or
by
using
the
A
uto
Mask
menu
to
create
a
mask
from a
waveform.
The
rst
method
involves
constructing
polygons
,
while
the
second
method
involves
the
use
of
a
reference
waveform.
Using the rst method, polygons are created to mask o failure regions of
the graticule. Up to eight polygons can be positioned in the graticule area.
Each polygon can have from 3 to 512 sides.Very complex masks can be
constructed by placing polygons within polygons. Similar to margin testing
discussed
above
,
this
method
allows testing
of
waveform
failure
rates
to
varying
tolerances
,
because
failures
are listed
individually
for
each
polygon.
Using the reference waveform method, masks
are constructed by adding a 1X
and 1Y tolerance around a reference waveform. This method is simple to use
,
though not as exible as the polygon method.
6-5

HP 83480A Specifications

General

Brand	HP
Model	83480A
Category	Measuring Instruments
Language	English