HP 8901B Operation And Calibration Manual page 112

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By specifying an offset frequency of zero, the Frequency Offset table can
also be accessed for measurements when an external LO is not being
used. Simply key in 27.3
SPCL
and then 0 MHz (the fOFS annunciator
will light in the display). The instrument is now ready to store the
calibration factors (up to
22)
for the second Sensor Module in the
Frequency Offset table using the entry procedure shown in Appendix B.
Once the cal factors have been stored, key in 27.0
SPCL
when you wish to
exit the Frequency Offset Mode and use the first Sensor Module. To re-enter
the Frequency Offset Mode and use the second Sensor Module, key in
27.1
SPCL.
No Power Sensor
RF Level (uncalibrated)
To make an uncalibrated RF power measurement without a power
sensor, connect a 500 cable and Type-N connector from the HP 8901Bs
INPUT port to the output of your signal source. Press the RF
POWER
key. The
HP
8901B will make an uncalibrated broadband power
measurement using its RF Peak detector. (Note that the HP 8901B
lights the
SPCL
key rather than the RF
POWER
key when it
is
using
the uncalibrated RF Peak detector to measure power.) Although the
accuracy of this measurement is signrficantly lower than a calibrated
power measurement made using a power sensor, it can be useful as
a means of determining if there is any input signal present at the
HP 8901Bs input. If a Sensor Module is connected to the HP 8901B,
the RF Peak detector can be selected by keying in 35.0
SPCL.
Tuned Level (uncalibrated)
To make an uncalibrated Tuned Level measurement (either with a Sensor
Module connected to the HP 8901B or with a BNC cable and Type-N
connector connected at the INPUT port) tune the
HP
8901B to the frequency
of the input signal and select
TUNED
RF
LEVEL.
The
H p
8901B will make
an uncalibrated Peak Tuned Level measurement. Although the accuracy
of this measurement is sigxuficantly lower than a calibrated
RF
Power
measurement, it can be useful for measuring input signals that are
drifting.
HP-/B The HP 8901B enables you to fully automate your RF Power measurements.
Refer to your HP 8901B Operation and Calibration Manual for setup and
programming information.