HP 8591C, User Manual, Page: 258 / 373

Visual Carrier Frequency and Visual-to-Aural
Frequency Difference Test Description
The visual carrier frequency test measures the frequency of the visual carrier,
as well as the visual-to-aural frequency difference. In channel measurement
mode, this test is executed by pressing the ON after one cycle
of a visual carrier level and visual-to-aural level difference test has been
completed.
To perform the visual carrier frequency and visual-to-aural frequency
difference test, the analyzer does the following:
1. Enables counting of the visual and aural carriers and calculates the aural
carrier difference.
2. In channel measurement mode, the frequency counter resolution can be
changed to 10 Hz without affecting measurement accuracy. Refer to the
specifications in the HP 8591C Calibration Guide.
Figure 8-2 shows the analyzer measuring the visual and aural carriers.
OEC 1993
CHANNEL
CNTR 55.2608 MHz
34.6 AT 10 34.64
NEXT
PEAK CHANNEL
LOG :
YES
Off
VIS
MAIN
MENU
CENTER MHz
SPAN MHz
WRES 3 MHz 75.0 RT
Figure 8-2. Measuring the Visual Frequency and Aural Frequency Difference
8-5