DATATEC HAMEG HM8135, User Manual

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Indroduction of the HM8135
coder and steps).
3 .7 Selecting frequency
After pressing the FREQ. key
9
, the display shows:
A new value can be entered from the data keypad
11
or
modified by the digital rotary knob
10
or by one of the four
context sensitive keys
5
. For more details, refer to the pa-
ragraph ”Setting parameters“. The frequency range is 1 Hz
to 1200 MHz. The resolution is 1 Hz. If a value is entered
with a higher resolution, the instrument makes a trunca-
tion keeping 1 Hz resolution.
3 .8 Selecting level
After pressing the LEVEL key
9
, the display shows:
A new value of the level can be entered from the data key-
pad
11
or modified by the digital rotary knob
10
or by one
of the four context sensitive keys
5
. For more details, re-
fer to the paragraph ”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 specified for a load of 50 Ω. The
choice of the unit is made by the keypad
11
dBm, mV or
µV . For the volt unit the instrument performs a three digits
resolution according to the range (mV/µV/nV).
3 .9 Selecting modulations
After pressing the MOD. key
9
, the display shows:
MODULATION MENU
AM FM PM – –>
MODULATION MENU
<– – FSK PSK GATE
The modulation type is selected by pressing one of the
four context sensitive keys
5
corresponding to:
❙AM (Amplitude modulation)
❙FM
(Frequency modulation)
❙PM (Phase modulation)
Caution:
If the AM modulation is activated, the instrument automatically
limits the level to +7 dBm in order to avoid an excess of the dyna-
mic of the ouput amplifier.
❙FSK (Frequency shift keying)
❙PSK (Phase shift keying)
❙GATE (Gate modulation)
The return to the previous display is possible by pressing
the PREV. key
3
.
After selecting the type of modulation (FM MENU), the dis-
play shows:
The selection of the parameters for AM/FM/PM is made by
pressing one of the four context sensitive keys
5
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
3
.
After selecting the SHAPE option (AM SHAPE MENU), the
display shows:
The shape of the internal modulation signal may be modi-
fied by the context sensitive keys
5
. The active signal is
pointed out by a triangle

.
The return to the previous menu is possible by pressing
the PREV. key
3
.
After selecting the Fmod option (AM MENU), the display
shows:
The frequency of the internal modulation signal may be di-
rectly changed by the numeric keypad
11
or modified by
the digital rotary knob
10
or by one of the four context
sensitive keys
5
.
The return to the previous menu is possible by pressing
the PREV. key
3
.
The frequency range is:
❙10 Hz to 200 kHz: Sine (Step 10 Hz)
❙10 Hz to 20 kHz: Triangle, Square, Sawthooth (Step 10 Hz)