HP 8591C User Manual page 257

Test Descriptions
Visual Carrier Level and Visual-to-Aural Level Cliff erence Test Description
The aural carrier needs to be within 4.5 MHz (f0.4 MHz) of the visual carrier
to be detected as the aural carrier. If the aural carrier cannot be detected, the
visual-to-aural frequency difference measurement cannot be done and a I'-"
will appear in the system measurement test data for the channel.
The SCBAMBLD YES NO softkey, when set to YES, does a max hold function
to catch and hold the values in non-suppressed sync tips.
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