User's Manual

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Chapter 5, Advanced Operations
Increasing Measurement Throughput
Time-to-first-reading after making new settings is usually much slower than the
repetitive reading rate once the first reading has been returned. The main
contributor to first-reading measurement time is hardware autoranging. Hardware
autoranging time can be eliminated by first establishing the expected AF and RF
signal levels into the Test Set. With these signal levels present, the Test Set will
autorange, allowing the operator to determine the attenuation and gain settings of
the RF input attenuator as displayed in the RF ANALYZER screen, and to
determine the various IF and audio gains as displayed in the AF ANALYZER
screen. The attenuation and gain settings determined in manual mode should be
recorded for use in writing the program.
In the control program, select Gain Control, Hold (default is Auto), and make the
settings recorded in manual mode. When the control program runs, the signal
levels into the Test Set need to remain relatively constant since autoranging has
been disabled.
If the automatic functions are turned off, the control program must set the gain
stages and frequency tuning before triggering a measurement. The automatic
functions can be turned off as follows:
Disable RF autotuning by setting the Tune Mode field to Manual using the
following command:
:RFAN:TMOD ’MANUAL’
Disable RF autoranging by setting the Input Atten field to Hold using the
following command:
:RFAN:ATT:MODE ’HOLD’
Disable AF autoranging by setting the Gain Cntl field to Hold using the
following command:
:AFAN:RANG ’HOLD’