Agilent Technologies E4445A PSA Series, Руководство пользователя, Страница: 69 / 74

Chapter 5 69
Hints and Tips
FAQs and Helpful Hints and Tips
Hints
an
d Tip
s
So the PSA start frequency should be adjusted enough to ensure that it
is at least 1 bucket width greater than the source minimum frequency.
(Find the source minimum frequency using the PSA command
SOURce:EXTernal:FREQuency:STARt? MIN)
Example 2: Bad Source Stop Frequency
Using 50 GHz PSA (E4448A) and 44 GHz source (for example, an
E8267D):
PSA settings:
• Start Freq = 42 GHz
• Stop Freq = 44 GHz
• Sweep Points = 101
• Offset = OFF
• Harmonic = OFF
This will cause the “Freq range of ext src exceeded” error.
Reason:
The signal source must be able to sweep one “bucket’s” worth of
frequency range after the requested PSA start frequency. In this case:
But 44.02 GHz is not in the range of the signal source.
So the PSA stop frequency should be adjusted enough to ensure that it
is at least 1 bucket width less than the source maximum frequency.
(Find the source maximum frequency using the PSA command
SOURce:EXTernal:FREQuency:STOP? MAX)
Example 3: Outside Analyzer Frequency Band
Using any PSA and any source:
PSA settings:
• Start Freq = 2.5 GHz
• Stop Freq = 3.5 GHz
Source Start Freq
42E(9) 0 +
44E 9
( )
42E 9
( )
–
101 1 –
------------------------------------------
⎝ ⎠
⎛ ⎞
–
1
-------------------------------------------------------------------------------- 41.98E 9
( )
= 41.98 GHz = =
Source Stop Freq
44E 9
( )
0 +
44E 9
( )
42E 9
( )
–
101 1 –
------------------------------------------
⎝ ⎠
⎛ ⎞
+
1
---------------------------------------------------------------------------------- 44.02E 9
( )
= 44.02 GHz = =