HP Cable Box 8591C Comparing Signals Using Delta Markers, Placing a Marker on the CAL OUT Signal

Comparing Signals Using Delta Markers

Using the spectrum analyzer, you can easily compare frequency and amplitude differences between signals, such as radio or television signal spectra. The spectrum analyzer’s delta marker function lets you compare two signals when both appear on the screen at one time or when only one appears on the screen.

Example: Measure the differences between two signals on the same display screen.

1.Connect the spectrum analyzer’s CAL OUT to the INPUT 75 0. Press (FEE-).

The calibration signal and its harmonics appear on the display.

2.Press (PEAK SEARCH] to place a marker at the highest peak on the display. The NEXT PK RIGHT and NEXT PK LEFT softkeys move the marker from

peak to peak. Press NEXT PK RIGHT to move the marker to the 300 MHz calibration signal. See Figure 4- 11.

The signal that appears at the left edge of the screen is the spectrum analyzer’s local oscillator (LO) and represents 0 Hz.

REF 4R R dRrn” AT 10 dB 28.45 dBrn”

PEAK

LOG

10

dB/

NEXT PK

RIGHT

Figure 4-11. Placing a Marker on the CAL OUT Signal

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