GW Instek SFG-830 User Manual - Manual (Page 33)

p. 30 SFG-830
(2) Negative Attenuator Calibration
To calibrate the negative attenuator, you should go through Calibration Number 9
~ 16 in turn, and perform the following 3 steps for each number.
n Set the Calibration Number.
o Use a DMM (FLUKE-8842) at DCV range to measure the output.
p Key in an appropriate Calibration Value to make the output to be the particular
value listed below:
n
Calibration Number
p
Output should be :
9 -39
± 0.1mV
10 -78
± 0.5mV
11 -156
± 1mV
12 -312
± 1mV
13 -625
± 2mV
14 -1.25V
± 10mV
15 -2.5V
± 10mV
16
o
Use a DMM (FLUKE-8842) at
DCV range to measure the
output
-5V
± 10mV
(3) Carrier Null Calibration
n Set the Calibration Number to 17.
o Use a distortion meter (DM-155 A/B) to measure the output.
p Key in an appropriate calibration value to minimize the distortion. Then go
through step
q
~
t
repeatedly to calibrate the output of Number 18 ~ 113.
q Set the Calibration Number (18 ~ 113, one number each time).
r Use a spectrum analyzer to measure the output.
s Set the Center Frequency of the spectrum analyzer to be X, where
X Calibration Number = − × +
( ) 17 312500 1000 .
t Key in an appropriate Calibration Value to minimize the power of frequency Y,
where Y
X
=
2
.
(4) Calibrating the Amplitude of Sine Wave
n Set the Calibration Number 114 ~ 115 (one number each time).
o Use a DMM (FLUKE-8842) at ACV range with 50 ohm load to measure the
output.
p Input an appropriate Calibration Value until the output to be the corresponding
figures as listed in the table below. Then go through step
q
~
s
repeatedly to
calibrate the output of Number 116~307.
q Set the Calibration Number 116 ~ 307 (one number each time).
r se a measuring receiver (HP-8902A or equivalent for high frequency amplitude
checks) at ACV range to measure the output.
s Input an appropriate Calibration Value to make the output to be as follows:
Calibration Number 114~307 Output Voltage
odd 1.77
± 0.005Vrms
even 3.54
± 0.01Vrms