Giga-tronics 8003, Руководство по эксплуатации

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8003 Precision Scalar Analyzer
2-100 Manual 20791, Rev. C, June 2001
To turn off Cal Factor correction completely, press
[CONFIG
] followed by the [ SENSORS CW FREQ ]
softkey. Then press the [ CORRCTN OFF ] softkey. You will be given the choice to turn off selected
sensor corrections, or all sensor corrections.
2.12.4 Sensor Offsets
In the CW mode, OFFSETS perform an analogous function to trace memory in swept mode. The offset
is a fixed dB value that is added or subtracted from the reading (much in the same way that a memorized
trace is subtracted from the measured trace). Offsets are useful for compensating for attenuators or
amplifiers between the DUT and the power sensor.
To enter an offset, press
[CONFIG]
followed by the [ SENSORS OFFSET ] softkey. Press the
appropriate [ SENSOR X OFFSET ] softkey where X is the sensor letter. Enter the offset value on the
numeric entry keypad and press the GHz/dB units key. Use a positive offset value for attenuation
between the DUT and sensor, and a negative offset value for gain.
2.12.5 Other CW Functions
When using the 8003 as a CW meter, some functions commonly found on CW meters come in handy.
These are RELative measurements, MAX hold and MIN hold, and Averaging.
Averaging reduces the amount of noise on the signal. Most often, averaging is used when measuring
very low level signals (below -40 dBm) to reduce the noise fluctuations of the reading. The number of
averages chosen determines the amount of filtering. To add averaging to a CW Power measurement,
first press the
[DISPLAY]
key, then select the AVG softkey. Either use the spin knob, or type in a
desired averaging number from 1 to 256. (If you enter a number on the numeric entry keypad, remember
to press the
[GHz/dB]
units key). Turn averaging on by pressing the [ AVG ON/OFF ] softkey.
MAX and MIN hold the maximum or minimum values recorded. This is often useful when adjusting a
device or sweeping its response. To activate MAX or MIN hold, press
[MEAS]
and select the [ CW
OPTION ] softkey. Then toggle either the [ MAXHOLDON/OFF ] or [ MINHOLDON/OFF ] softkey to
activate the function. MAX or MIN hold will be in effect as long as the function is ON. If the [ CW
OPTION ] softkey is in dim, dark blue, the channel on which you are trying to set MAX or MIN hold is
Figure 2-57: Averaging Used to Reduce Noise
AVG
ON/OFF
AVG N
CONFIG
SEN A OFFS 0.00 dB
FREQ 5.00 G z
-67.63 dBm
SMOOTH-
ING
RETURN
CH1 - WITH AVERAGING
AVERAGE FACTOR
16
H