Справочник Пользователя для Rohde & Schwarz Inc SLV8000

2100.4400.32

- 5.88 -

E-2

This window is used to precorrect the phase of the sound subcarrier for combined opera-
tion. Precorrection is performed separately for each of the two FM sound subcarriers
(Carrier 1 and Carrier 2). Two setting items are defined for each of the two FM sound sub-
carriers.

This sound phase shifter modifies the phase of the sound subcarrier as a function of the
low-frequency drive of the picture signal in order to precorrect the phase of the sound sub-
carrier during combined operation.

When the sound phase shifter is switched on, its characteristic curve is determined using
two inset points. 

The reference for setting the position is initially a value of 37.5% for the rear black shoulder.
Smaller values are in the range of the sync pulse. A value of 0% corresponds to a sync
pulse amplitude of 500 mV. Larger values are in the picture range. A value of 90% corre-
sponds to picture amplitude of 700 mV. 

There is an additional condition that the setting for inset point 1 must always be greater than
that of inset point 2. The sharpness of the two inset points is determined by the slope of the
characteristic curve at these points. The magnitude of the setting determines the magnitude
of the phase shift. A setting of 50% specifies the maximum value. The sign of the setting
value determines whether the phase is shifted in the positive or negative direction.

Precorrection

Switches the sound phase shifter on or off.

Inset Point 1

Determines the position of the 1st inset point referred to the drive of the 
picture signal.

Slope 1

Determines the sharpness at the 1st inset point.

Inset Point 2

Determines the position of the 2nd inset point referred to the drive of the 
picture signal.

Slope 2

Determines the sharpness at the 2nd inset point.