Hameg HM8134-3X Handbuch Manual Download

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Subject to change without notice

O p e r a t i n g t h e i n s t r u m e n t

Indroduction of the HM8134-3

First time operation

Before starting the instrument the ﬁ rst 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 trans-
former of protection class II.

–   No visible damage to the instrument.
–   No visible damage to the line cord.
–   No loose parts ﬂ oating around in the instrument.

Switch-on

After depressing the red power key

, the display of the

HM8134-3 will successively show the following messages:

– the type (SYNTHESIZER) and the version of the instrument

(HM8134-3)

the self-test messages ”RAM checking“ and ”DDS loading“
(RAM = Random Acess Memory; DDS = Direct Digital Syn-
thesis)

– 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 HM8134-3 has the conﬁ guration stored in
the conﬁ guration memory 0. The output signal is disabled after
switch-on by default.

Factory conﬁ guration

At delivery the instrument is adjusted for a basic set-up:
– Frequency:

1200

MHz

– Level:

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 se-

veral beeps. This procedure is especially suited in case of
doubt.

STOP

Caution:

The 10 memories storing conﬁ gurations are erased
and replaced by the previous basic adjustments.

Operating the instrument

Main display

This display shows the frequency and the level of the RF output
signal and the reference in use (INTernal or EXTernal). If no
modulation (AM, FM, PM) is turned on, the display shows:

Moreover, it contains some modulation parameters (for example
in case of AM modulation, shape SQR and Fmod = 1 kHz).

This state is left by pressing one of the function keys

or the

MENU key

ESC key

The ESC key

allows the user to return to the main display,

to unselect the current function

or to cancel the numeric

keypad input.

Setting parameters

Once a parameter is selected (for example FREQ.) with a func-
tion key

, a new value for this parameter can be entered from

the data keypad

or modiﬁ ed by the digital rotary

or by

one of the four context sensitive keys

below the displayed

marks – and + .

The operation of the data keypad is conventional. Depress suc-
cessively the numeric keys representing the parameter value
and at the end the unit key (for example MHz or dBm). Note that
it is not necessary to enter any leading zeros. The instrument
always displays at least one digit on the left of the comma.
Before the unit selection, it is possible to cancel the value by
pressing the ESC key

. In this case the previous value is

restored.

The encoder

modiﬁ es 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

and the value can be increased or

decreased by operating – or +. An unproper value is announ-
ced by a warning message and the sound indicator if activated
(except for out of range of encoder

and steps).

Selecting frequency

After pressing the FREQ. key

, the display shows:

A new value can be entered from the data keypad

or mo-

diﬁ ed by the digital rotary

or by one of the four context

sensitive keys

. For more details, refer to the paragraph

”Setting parameters“. The frequency range is 1 Hz to 1200 MHz.