Keysight Technologies N5247B, Service Manual

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5-66 Keysight N5247B Service Guide
Theory of Operation
Noise Measurement Group Operation (Option 029)
5-
A9 Noise Receiver Board
In the A9 noise receiver board, the IF noise signals from the A59 noise
downconverter are further amplified and filtered before being sent to ADC for
sampling. The 10 MHz – 6 GHz noise signals that passed through the A59
noise downconverter are amplified, filtered, and mixed with the LO synthesized
signal to produce IF noise signals. These are filtered and sent to the ADC for
sampling. In the ADC, the signals are processed and converted to digital form
at the sampling rate of 40 MHz. The digitized data is then sent to the A18
system motherboard via the data bus.