30
Subject to change without notice
O p e r a t i n g c o n t r o l s
The resolution is 1 Hz. If a value is entered with a higher
resolution, the instrument makes a truncation keeping 1 Hz
resolution.
Selecting level
After pressing the LEVEL key
, the display shows:
A new value of the level can be entered from the data keypad
or modifi ed by the digital rotary
or by one of the four
context sensitive keys
. For more details, refer to the para-
graph ”Setting parameters“.
The level range is:
– -135 dBm to +13 dBm without amplitude modulation
– -135 dBm to +7 dBm with amplitude modulation
– The resolution is 0.1 dBm.
The level displayed is specifi ed for a load of 50 Ω. The choice of
the unit is made by the keys dBm, mV or μV
. For the volt unit
the instrument performs a three digits resolution according to
the range (mV/μV/nV).
STOP
Caution:
If the AM modulation is activated, the instrument
automatically limits the level to +7 dBm in order to
avoid an excess of the dynamic of the ouput ampli-
fi er.
Selecting modulations
After pressing the MOD. key
, the display shows:
MODULATION MENU
MODULATION MENU
AM FM PM
AM FM PM – –>
MODULATION MENU
MODULATION MENU
<– – FSK PSK GATE
FSK PSK GATE
The modulation type is selected by pressing one of the four
context sensitive keys
corresponding to:
– AM (Amplitude modulation)
– FM
(Frequency modulation)
- PM
(Phase
modulation)
- FSK (Frequency shift keying)
- PSK (Phase shift keying)
– GATE
(Gate
modulation)
The return to the previous display is possible by pressing the
PREV. key
.
After selecting the type of modulation (FM MENU), the display
shows:
The selection of the parameters for AM/FM/PM is made by
pressing one of the four context sensitive keys
corres-
ponding to:
– The shape of internal modulation signal
– The frequency of the internal modulation signal
– The deviation (or depth in AM)
– The
modulation
state
The return to the previous display is possible by pressing the
PREV. key
.
After selecting the SHAPE option (AM SHAPE MENU), the
display shows:
The shape of the internal modulation signal may be modifi ed
by the context sensitive keys
. The active signal is pointed
out by a triangle
.
The return to the previous menu is possible by pressing the
PREV. key
.
After selecting the Fmod option (AM MENU), the display
shows:
The frequency of the internal modulation signal may be directly
changed by the numeric keypad
or modifi ed by the digital
rotary
or by one of the four context sensitive keys
.
The return to the previous menu is possible by pressing the
PREV. key
.
The frequency range is:
– 10 Hz to 200 kHz:
Sine (Step 10 Hz)
– 10 Hz to 20 kHz: Triangle, Square, Sawthooth (Step 10 Hz)
The modulation is turned on by pressing the context sensitive
key
below the string OFF. One time for turning the internal
source on (INT) and a second time for turning the external
source on (EXT). The active source is pointed out by a triangle
beside the option.The indicator LED of the MOD.OUTPUT is
lighting.
Pressing the context sensitive key
once again, the modulation
will be deactivated (OFF).
The return to the previous menu is possible by pressing the
PREV. key
.
With external AM activated, the only modifi able option is the
modulation depth (see paragraph ”Amplitude modulation“).
The external modulation frequency for AM must be in the
range:
– 10 Hz to 100 kHz
With external FM or PM activated, several cases are possible:
– DC coupled (DC – 100 kHz)
– AC coupled (100 Hz – 100 kHz)
– Deviation (see corresponding paragraph)
