HP 8901B Operation And Calibration Manual page 247

Operation Model
8901B
Front-Panel
Key
or
Special Function Code
Measurement
Mode
Action:
AM Calibration
Factor
Enter the appropriate front-panel key or Special Function code to manipulate the AM Calibration
Factor as described in the following table:
Program Code
Disable
I
Any
I
16.0 SPCL 16.0SP
Enable
AM
(From CALIBRATE mode)
Any
sc
(Blue
Key)
SAVE CAL
16.1 SPCL 16.1 SP
~
AM
Any
Display
Calibrating or Cross Checking Another HP 8901 or 8902 RF Signal Analyzer
To compute an AM calibration factor for another RF signal analyzer that
has
no internal calibrator,
or that has an internal calibrator that is to be cross checked, use the Modulation Analyzer and its
calibrator as follows:
~~
CF
(Blue Key)
16.2 SPCL 16.2SP
Yo
CAL FACTOR'
1.
2 .
3 .
4.
5 .
6.
3-142
AM
Connect the Modulation Analyzer's CALIBRATION AM/FM OUTPUT to the RF input of the
other RF signal analyzer.
Select 13.0 SPCL for the Modulation Analyzer. Record the value that appears on the display.
This is the computed, calibrated, peak AM depth (excluding noise).
Select 1 3 . 1 SPCL for both instruments. Record the value that appears on the display of the RF
signal analyzer. (If display jitter makes readings difficult, select 5 . 1 SPCL.) The displayed value
is the weighted, peak, residual
AM depth of the calibrator's unmodulated output as demodulated
by the RF signal analyzer.
Select 13.2 SPCL for both instruments. Record the value that appears on the display of the
RF signal analyzer. This value is the demodulated, positive, peak AM depth of the calibrator's
modulated output. (If display jitter makes readings difficult, select 5 . 1 SPCL.)
On the
RF
signal analyzer, select PEAK-. Note the value displayed on the RF signal analyzer. If
the difference between the results of steps 4 and 5 is three counts or less in the least significant
digit, an average between the
Cwo
need not be computed; use the result from step 4. If the difference
between the two results is greater than three counts in the least significant digit, compute the
average as follows:
(result of step 4)
+
2(resuZt of step 5)
3
(13.2 result) =
Compute the AM calibration factor of the RF signal analyzer as follows:
(13.2 result) - (13.1 result)
(13.0 result)
AM Calibration Factor (%)
=
100
x
Calibration