Agilent Technologies 8935 Series, Руководство пользователя

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288 Chapter 10
Block Diagrams
RF Analyzer Section
RF Analyzer Section
Frequency Conversion
The A2A115 Downconverter, see Figure 10-3 on page 290 , produces an
IF of 114.3, 385.7 or 614.3 MHz. The LO is provided by the A2A22
Receiver Synthesizer, see
Figure 10-4 on page 291 . The IF frequencies
developed are as follows in Table 10-1 .
Filters are automatically switched in to remove image and other
interfering signals. The frequency ranges of the filters are as follows:
• 150 MHz low-pass
• 150 MHz - 386 MHz bandpass
• 350 MHz - 650 MHz tunable bandpass
• 650 MHz - 1000 MHz tunable bandpass
• 1400 MHZ - 2200 MHz tunable bandpass
Modulation Measurement
The A2A21 Receiver assembly demodulates the IF into its FM, AM, and
SSB components, see
Figure 10-5 on page 292 . The demodulated signal
is sent to the Audio Analyzer section for measurement.
Table 10-1 IF Frequencies
Input RF (MHz) 1st LO (MHz) IF (MHz)
0 to 385.7 614.7 to 1000 614.3
385.7 to 800 500 to 914.3 114.3
800 to 1000 685.7 to 885.7 114.3
1400 to 2200 1014.3 to 1814.3 385.7