Storing Trace Memories; Viewing Normalized Parameters - HP 8517B Operating & Service Manual

Storing Trace
Memories
Viewing Normalized
Parameters
If you view the response of a short circuit, notice that:
•
Changing Port 1 attenuator has negligible effect on S
•
Changing Port 2 attenuator has negligible effect on S
This is due to the way the attenuators are paired. Both the reference and the
test signal are changed by approximately equal amounts.
When viewing S or S
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offsets the marker reading by the difference value between Port 1 attenuator
and Port 2 attenuator.
To compensate for the main frequency response effects due to changing
the attenuators, use the HP 8510C trace memories and trace mathematics
function, as explained below:
1. Connect the thru used for calibration and set the port attenuators to the
value used for device measurement.
2. Recheck the user parameter levels, then press PARAMETER [
3. Press MENUS
[DISPLAY]
Press
DISPLAY: {DATA-->MEMORY n}
memory 1. This trace represents the frequency response difference
between the S signal path calibration and the measurement.
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4. Press PARAMETER
{SELECT DEFAULTS}
{DEFAULT to MEMORY: 2}
{DATA-->MEMORY 2}
The S trace is now stored in trace memory 2. This trace is the
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frequency response difference of the S
and measurement.
Use the traces stored in memory 1 and memory 2 to normalize the corrected
data to the new levels after the attenuation is changed. The next example
uses normalization for S
1. Press MENUS
[DISPLAY]
2. Press PARAMETER
3. Press PARAMETER
4. Press PARAMETER
{SELECT DEFAULTS}
{DEFAULT to MEMORY: 1}
{MATH ( / ) }
, however, changing Port 1 or Port 2 attenuators
, then
{DATA AND MEMORIES}
to store the S
, then press the following
[S ]
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signal path between calibration
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or S only. To view the corrected parameters:
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, then
{DATA AND MEMORIES}
and view the S measurement.
[S ]
11
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and view the S measurement.
[S ]
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, then the following
[S ]
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HP 8517B S-Parameter Test Set Manual 3-11
marker reading
11
marker reading
22
].
S
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.
trace in default trace
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menu keys:
DISPLAY:
menu keys:
DISPLAY: