Fluke 96000 Series Service Manual page 122

96000 Series
Service Manual
During calibration adjustment, measure the output amplitude to determine the
absolute level error at the amplitude/frequency combination set. Make an entry
via a front panel key sequence or via GPIB command sequence to adjust the
output to correct any error from nominal, and store an appropriate correction
factor in the internal non-volatile memory. This process is required at a variety of
amplitude/frequency points throughout the amplitude and frequency range of the
instrument. Users of the calibration process should familiarize themselves with
the entire calibration adjustment process prior to attempting any calibration
adjustment operations.
Environmental and warm up conditions required for performing the calibration
adjustments are as follows:
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Each calibration adjustment procedures lists the equipment required to perform
the procedure and a figure detailing the equipment connections for the
procedure. Perform the procedures in sequence, ensuring that all prior
equipment connections have been removed before starting a new procedure. For
the 96270A, the Microwave Output may be adjusted independently.
During the course of the adjustment process, depending on which adjustment
procedure is in progress, the process may prompt for an AC Measurement
Standard, followed by a Power Meter and sensor(s), a Power Sensor with a 6 dB
attenuator fitted, and finally, a Spectrum Analyzer/Measuring Receiver. At
various points within the process, values previously adjusted using one reference
device are transferred to another for subsequent use.
To minimize the number of connection changes required during Instrument
calibration adjustment, the steps are sequenced so that all steps requiring the AC
Measurement Standard, for example, are performed together, as are the various
steps requiring each of the other required reference devices.
Calibration adjustment of the Instrument is a systematic process. At each step,
the display shows the adjustment target level and frequency values, and directs
the user to the required measurement device. Following measurement of the
expected target value, use the Instrument alphanumeric keypad to enter the
measured value, followed by the softkeys, Accept Adjust, and Next Target.
Within any procedure the Instrument calibration adjustment must be completed in
the order presented. Subsequent steps rely on measurement values entered
during previous steps. For example, to repeat part of the procedure after an error
or to pause and subsequently resume the procedure, skip to the first step of the
affected adjustments and proceed from that point on. To do so, push the Find
Point softkey, then use the blue arrow keys, rotary knob, or numeric keypad
(followed by ) to select the point number desired, then push Go to Point to
complete the process. Use the information provided in the text box below the
Adjustment Point as an aid to find the point.
The specifications listed in Chapter 1 contain some conditions for which
performance is not warranted or specified as "typical" (for example, at
frequencies below 100kHz at levels -47 dBm, modulation, etc). The adjustment
sequence also includes points for adjusting performance in these areas, which
have no impact on the warranted performance of the Instrument. These
additional points are adjusted at manufacture or following repair but need not be
routinely re-adjusted during normal periodic recalibration operations. If
necessary, omit the relevant steps in the calibration adjustment sequence if the
4-2
Ambient temperature of the test environment is 23 ±1 °C.
Warm up time (continuous operation) for the Instrument, with all covers in
place, is 1 hour (24 hours for adjusting the Reference Frequency).