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ANALOG MODULATION MODE
3-53
LF phase
When an internal source has been selected, its phase relative to the second modulation oscillator
(if fitted) can be changed by pressing
[Mod. Src Phase]
and entering the required value. Where
two internal modulation frequencies are active, the starting phase difference between the two
signals can be set up and the phase angle is referred to the currently selected oscillator.
Mod. Src
Phase
LOCAL
Modulation Source Phase Control
C1888
Int F4 Phase :
Fig. 3-52 LF phase control
Source selection - external
An external source may be selected by pressing
[Select External]
. The
External Source Selection
Menu
is then displayed on the screen (This menu is displayed immediately when pressing
[Select
Source]
if the currently selected source is external). This menu allows the choice of two input
sockets EXT MOD 1 INPUT and EXT MOD 2 INPUT and AC, ALC, or DC coupling by pressing
the appropriate soft key. The pictograms at the end of each line show a symbolic arbitrary
waveform when an external source is selected. This symbol also appears on the main menu. A
horizontal bar is shown when a source is not selected or is not available. When the input is DC
coupled, small frequency offsets can be reduced by using the nulling facility. Nulling can be
effected by pressing
[DCFM Nulling].
Ext1 AC
Coupling
Ext1 ALC
Coupling
Ext1 DC
Coupling
Ext2 AC
Coupling
Ext2 ALC
Coupling
Ext2 DC
Coupling
LOCAL
Select
External
External Source Selection Menu
Current Modulation: FM
C0007
Ext Mod 1
Ext Mod 1
Ext Mod 1
Ext Mod 2
Ext Mod 2
Ext Mod 2
AC Coupled
ALC Coupled
DC Coupled
AC Coupled
ALC Coupled
DC Coupled
Fig. 3-53 External source selection menu