Atec Agilent-8757D - Manual (Page 2)

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The Agilent 8757D has four independent display
channels that process the signals from the Agilent
85037 series precision detectors, 85025 and 85026
detectors, and the 85027 series directional bridges
for logarithmic display, in single channel or ratio
mode. Three (optionally four) detector inputs are
provided.
Display
Horizontal resolution
The number of points (horizontal resolution)
that can be selected depends on the number of
traces displayed.
Network analyzer Traces Selectable number of points
8757D 1 101, 201, 401, 801, 1601
2 101, 201, 401, 801
3, 4 101, 201, 401
LCD Display 640 (horizontal) x 480 (vertical) resolution
A display is considered faulty if:
• A complete row or column of “stuck” or “dark”
pixels.
• More than six “stuck on” pixels (but not more
than three green) or more than 0.002% of the
total pixels are within the LCD specifications.
• More than twelve “dark” pixels (but no more
than seven of the same color) or more than
0.004% of the total pixels are within the LCD
specifications.
• Two or more consecutive “stuck on” pixels or
three or more consecutive “dark” pixel (but no
more than one set of two consecutive dark
pixels) “Stuck on” of “dark” pixels less than
6.5 mm apart (excluding consecutive pixels)
Display modes
All analyzer display channels can display any one
of the detector inputs or any ratio combination
of detector inputs.
Log magnitude
dBm: single channel power measurement
dB: relative power measurement (ratio or relative
to trace memory)
SWR
Relative measurements (normalized or ratio
measurements) can be displayed in SWR.
Channels 1 and 2 only: 401 points or fewer
AUX voltage
The rear panel BNC input ADC IN can be mea-
sured and displayed in volts (–10 to +10 volts).
Typical maximum error is 60 mV.
Color settings
Up to 8 operator-selectable colors are available
for LCD attributes, such as the grid, measurement
traces, and labels.
Sweep time
The minimum sweep time depends on the num-
ber of traces displayed and the number of points
selected.
Minimum sweep time (ms)
Number (log magnitude format)
of points 1 trace 2 traces 3 traces 4 traces
101 40 50 60 70
201 50 75 90 100
401 100 100 150 200
801 200 250
1601 400 NA NA NA
Averaging
2, 4, 8, 16, 32, 64, 128, or 256 successive traces can
be averaged.
Smoothing
Provides a linear moving average of adjacent data
points. The smoothing aperture defines the trace
width (number of data points) to be averaged, and
ranges from 0.1% to 20% of the trace width.
Normalization
Traces are stored and normalized with the highest
resolution, independent of display scale/division or
offset. With adaptive normalization on the Agilent
8757D, calibration data is interpolated when the
frequency span is decreased.
Limit lines
Limit lines facilitate quick pass/fail decisions.
Limits can be any combination of flat or sloped
lines or single points up to 12 segments. They
are only available for channels 1 and 2, for traces
with 401 points or fewer, and can be stored in
save/recall registers 1 through 4.
Agilent 8757D scalar network analyzer