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Absolute Measurement Fundamentals
5
Agilent E5505A User’s Guide
113
Using a Signal Generator
When using a signal generator as a reference source, it is important that the
generator’s noise characteristics are adequate for measuring your device.
Tuning Requirements
Often the reference source you select also serves as the VCO source for the PLL
measurement. (The VCO source can be either the DUT or the reference source.)
To configure a PLL measurement, you need to know the following tuning
information about the VCO source you are using.
•
Tuning Constant (Hz/V) (within a factor of 2)
•
Tuning Voltage Range (V)
•
Center Voltage of Tuning Range (V)
•
Input Resistance of Tuning Port (
Ω
)
The primary consideration when evaluating a potential VCO source for your
measurement is whether it provides the test system with sufficient capture
and drift tracking ranges to maintain lock throughout the measurement. To
make this determination, you must estimate what the drift range of the
sources you are using will be over the measurement period (thirty minutes
maximum). (Details on the relationship between the capture and drift tracking
ranges and the tuning range of the VCO source are provided in
. This
information helps you evaluate your VCO source based on the estimated drift
of your sources.)
lists the tuning parameters for several VCO options.
Table 12
Tuning Characteristics of Various VCO Source Options
VCO Source
Carrier
Freq.
Tuning Constant
(Hz/V)
Center
Voltage
(V)
Voltage Tuning
Range (
±
V)
Input
Resistance
(
Ω)
Tuning
Calibration
Method
Agilent 8662/3A
EFC
DCFM
υ
0
5 E – 9
x
υ
0
FM Deviation
0
0
10
10
1E + 6
1 k (8662)
600 (8663)
Measure
Calculate
Calculate
Agilent 8642A/B
FM Deviation
0
10
600
Calculate
Agilent 8644B
FM Deviation
0
10
600
Calculate
Содержание E1420B
Страница 24: ...24 Agilent E5505A User s Guide ...
Страница 46: ...46 Agilent E5505A User s Guide 2 Introduction and Measurement ...
Страница 128: ...128 Agilent E5505A User s Guide 5 Absolute Measurement Fundamentals ...
Страница 226: ...226 Agilent E5505A User s Guide 7 Residual Measurement Fundamentals ...
Страница 322: ...322 Agilent E5505A User s Guide 13 Baseband Noise Measurement Examples ...
Страница 340: ...340 Agilent E5505A User s Guide 14 Evaluating Your Measurement Results ...
Страница 358: ...358 Agilent E5505A User s Guide 15 Advanced Software Features ...
Страница 386: ...386 Agilent E5505A User s Guide 16 Reference Graphs and Tables ...
Страница 392: ...392 Agilent E5505A User s Guide 17 System Specifications ...
Страница 404: ...404 Agilent E5505A User s Guide 18 System Interconnections ...
Страница 452: ...452 Agilent E5505A User s Guide 20 PC Digitizer Performance Verification ...
Страница 466: ...466 Agilent E5505A User s Guide 21 Preventive Maintenance ...