Principle of the N9340B spectrum analyzer
The real-time frequency analyzer has corresponding filters and detectors for different frequency signals, and a synchronized multi-tasking scanner transmits the signals to the CRT screen.
The scan-tuned spectrum analyzer is a local oscillator whose input signal is directly applied to the mixer and then modulated by the attenuator. The scan generator synchronized with the CRT generates an oscillation frequency that changes linearly with time, and is mixed by the mixer and the input signal. wave.
Reading of the N9340B spectrum analyzer
Level reading: The reference level REF is mainly used. The uppermost horizontal line on the instrument screen graphic is the reference level line. The level indicated by this line is the reference level, and its value and unit are displayed in the upper left corner of the screen.
Frequency reading: The center frequency, the starting frequency, and the ending frequency in the graph are three vertical lines, and the number of frequencies represented by each is displayed at the bottom of the screen.
Use of the cursor: Press the MKR button and a flashing cursor will appear on the screen curve. The level and frequency of the cursor position are displayed in the upper left corner of the screen. The cursor can be moved at will, and where it is moved, the frequency and level of the place are displayed.