DATATEC HAMEG HM8135, Руководство пользователя

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Indroduction of the HM8135
3 Indroduction of
the HM8135
3 .1 First time operation
Before starting the instrument the first time, please check
the following:
❙The line voltage indicated on the rear panel corresponds
to the available line voltage, also, the correct fuses for this
line voltage are installed. The fuses are contained in the
line voltage connector housing.
❙The connection to the mains is either by plugging into a
socket with safety ground terminal or via an isolation
transformer of protection class II.
❙No visible damage to the instrument.
❙No visible damage to the line cord.
❙No loose parts floating around in the instrument.
3 .2 Switch-on
After depressing the red power key
1
, the display of the
HM8135 will successively show the following messages:
❙the type (SYNTHESIZER) and the version of the
instrument (HM8135)
❙the self-test messages ”RAM checking“ and ”DDS
loading“ (RAM = Random Acess Memory; DDS = Direct
Digital Synthesis)
❙Optional interface:
Second Com Interface: NONE, RS-232 (HO890), IEEE488
(HO880), USB (HO870)
❙Optional OCXO:
FREQUENCY REFERENCE
OCXO OPTION > NO (YES)
❙the reference soure in progress (internal or external):
FREQUENCY REFERENCE
Internal (External)
After switch-on the HM8135 has the configuration stored
in the configuration memory 0. The output signal is
disabled after switch-on by default.
3.3 Factory configuration
At delivery the instrument is adjusted for a basic set-up:
❙Frequency: 3000 MHz
❙Level: +7 dBm
❙No modulation
❙Reference source: internal
❙Fmod: 1 kHz, Shape: sine (for all modulations)
❙Dev: 20 kHz (FM), Dev: 1 rad (PM) , Depth: 50% (AM)
❙Contrast: maximum
❙Sound indicator: none
❙Interface parameters: 4800 baud / 1 stopbit / 8 data bits
This basic adjustment can be recalled at any time as
follows:
❙Switch off the unit.
❙Switch on the unit and hold the ESC key until you hear
several beeps. This procedure is especially suited in case
of doubt.
3 .4 Main Display
This display shows the frequency and the level of the RF
output signal and the reference in use (INTernal or EXTer-
nal). If no modulation (AM, FM, PM) is turned on, the dis-
play shows:
Moreover, it contains some modulation parameters (for ex-
ample in case of AM modulation, shape SQR and Fmod =
1 kHz).
This state is left by pressing one of the function keys
9
or
the MENU key
7
.
3 .5 ESC key
The ESC key
13
allows the user to return to the main dis-
play, to unselect the current function
9
or to cancel the
numeric keypad input.
3 .6 Setting parameters
Once a parameter is selected (for example FREQ.) with a
function key
9
, a new value for this parameter can be en-
tered from the data keypad
11
or modified by the digital ro-
tary
10
or by one of the four context sensitive keys
5
be-
low the displayed marks – and + .
The operation of the data keypad is conventional. Depress
successively the numeric keys representing the parame-
ter value and at the end the unit key (for example MHz or
dBm). Note that it is not necessary to enter any leading ze-
ros. The instrument always displays at least one digit on
the left of the comma. Before the unit selection, it is pos-
sible to cancel the value by pressing the ESC key
13
. In this
case the previous value is restored.
The encoder
10
modifies the value of the digit underlined
by the cursor (if the cursor underlines a blank position, it is
considered as 0). The cursor is shifted to another position
by pressing the keys below
the 2 arrows
5
and the value
can be increased or decreased by operating – or +. An un-
proper value is announced by a warning message and the
sound indicator if activated (except for out of range of en-
Caution:
The 10 memories storing configurations are erased and replaced
by the previous basic adjustments.