Agilent Technologies PSA Series - 2.3.2 Video BW

Chapter 5 71
Hints and Tips
FAQs and Helpful Hints and Tips
Hints and Tips
asking the source to start its sweep at −0.8 GHz. In this case:
But
−0.8 GHz is not in the range of the signal source.
So you can either:
• increase the offset to
≤ −3 GHz
or
• reduce the stop frequency to
≤ 2.8 GHz
Example 5: Offset Causes Bad Source Stop Frequency
Using PSA (13.2 GHz and above) and a 6 GHz source (for example, an
E4438C):
PSA settings:
• Start Freq = 10 GHz
• Stop Freq = 12 GHz
• Sweep Points = 101
•Offset =
−5 GHz, On
•Harmonic = OFF
This will cause the “Freq range of ext src exceeded” error.
Reason:
The signal source is being asked to sweep outside its frequency range.
In this case:
Source Start Freq
2.5E 9() 2.8E 9()–()+
3.0E 9() 2.5E 9()–
101 1–
---------------------------------------------
⎝⎠
⎛⎞
–
1
--------------------------------------------------------------------------------------------------------------- 0.8E 9() = –0.8 GHz–==
Source Stop Freq
3.0E 9() 2.8E 9()–()+
3.0E 9() 2.5E 9()–
101 1–
---------------------------------------------
⎝⎠
⎛⎞
+
1
--------------------------------------------------------------------------------------------------------------- 0 . 2 E 9() = 200 MHz==
Source Start Freq
10E 9() 5E 9()–()+
12E 9() 10E 9()–
101 1–
------------------------------------------
⎝⎠
⎛⎞
–
1
------------------------------------------------------------------------------------------------------ 4.98E 9() = 4.98 GHz==