Tektronix AFG3000 Series Service Manual page 93

AFG3xxx Measurement
Function Frequency Fundamental
sine 20.00 kHz
reading (dBm) A
1
reading – reference B
1
B = A – A (dBc)
n n 1
Bn/20
C = 10 C
n 1
2
∑
C
THD =
n
THD
n 2
=
= ---------------------- -
C
1
Sample: reading
reading – reference
C =
n
2
∑
C
n
THD
n 2
=
= ---------------------- -
C
1
AFG3000 Series Arbitrary/Function Generators Service Manual
6. Measure and record each level (A
20 kHz sine wave.
7. Calculate the each B
2nd
= reference
20 kHz 40 kHz
= A =
2
= 0 B =
2
= 1 C =
2
1.5 dBm –58.5 dBm
0 –60 dBm
1.000 0.001
When all the harmonic components are
NOTE.
THD can be skipped because it is THD<0.2%.
8. Verify that the THD is less than 0.2%.
9. (AFG3xx2 only) Repeat steps 2 through 8 for the channel 2 output.
to A
1
to B , C to C
1 7 1 7
3rd 4th
60 kHz 80 kHz
A = A =
3 4
B = B =
3 4
C = C =
3 4
–58.5 dBm –63.5 dBm
–60 dBm –65 dBm
0.001 0.000562
0.1987%
Performance Verification
) to the seventh harmonics of the
7
value and the THD.
5th 6th
100 kHz 120 kHz
A = A =
5 6
B = B =
5 6
C = C =
5 6
–58.5 dBm –63.5 dBm
–60 dBm –65 dBm
0.001 0.000562
62dBm or less, the calculation of
–
7th
140 kHz
A =
7
B =
7
C =
7
Limit
< 0.2%
–63.5 dBm
–65 dBm
0.000562
Limit
< 0.2%
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