Automatic Operation - HP 8901B Operation And Calibration Manual

Model 8901B Operation
Automatic Operation
FUNCTIONS
AUTOMATIC OPERATION
DESCRIPTION
The Automatic Operation function
fulfills two
major functions: (1) To configure the Modulation
Analyzer
to
automatically tune to the largest detectable RF input signal and to make the selected
measurement. (2) To cancel most special functions.
Specifically, Automatic Operation sets special functions with prefixes 1 through 10
to
their 0-su5x
state, cancels many special functions with prefixes greater than 10, and overrides all service special
functions (prefixes 0, 40, or greater). (Refer to Special hnctions on page
3-237
for details on special
functions 1 through
39.
Refer to Section 8 of the Service Manual for details on Service Special
Fbnctions.) Automatic Operation also cancels some front-panel settings (TRACK MODE, RANGE
HOLD, and DISABLE ERROR.
Those features that are not affected by Automatic Operation include H P or LP FILTERS, FM DE-
EMPHASIS, MEASUREMENT, CALIBRATION, DETECTOR, DISPLAY, and RATIO. RF level-
and modulation-related calibration factors remain intact. Limit settings (Special Fbnction 14) and
Frequency Offset Control (Special Fbnction
27)
are also not affected.
PROCEDURE
To enter the Automatic Operation mode, select Automatic Operation. The instrument will immediately
re-tune
to
the input signal and make the measurement selected.
HP-IB PROGRAM CODE
AUTOMATIC OPERATION = AU
COMMENTS
Input/Output Status
MODULATION OUTPUT/AUDIO INPUT is blanked temporarily during the automatic tuning
process initiated by selecting Automatic Operation.
The Value of the Automatic Operation Capability
Automatic Operation is the easiest way
to
make measurements in applications where only a single
carrier is present at the RF INPUT. The instrument configures itself
to
meet the needs of most
measurement situations, and all error messages signaling inaccurate measurements are enabled.
Range Hold is Opposite to Automatic Operation
The converse of the Automatic Operation mode is the Range Hold function.
Restrictions on Entering Automatic Operation
The instrument cannot enter the Automatic lkning mode when making any tuned RF level
measurements.
Automatic Operation
3-207