DATATEC HAMEG HM8135, User Manual

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Remote Operation
6 .14 FM (Frequency Modulation)
Commands in order to modify FM parameters
Syntax:
:FM[:DEViation]
<
NUM
>
(1)
:FM[:DEViation]? (2)
Sending line (1) the FM deviation can be modified. The
< NUM > parameter is a NR1 or NR2 or NR3 number (see
paragraph Syntax conventions). No unit has to follow the
number, Hz unit is the default one. The value is rounded to
the resolution.
Sending line (2) the instrument returns the current FM de-
viation. The instrument sends back a string representing a
NR3 decimal number.
:FM:SOURce INTern | EXTern (3)
:FM:SOURce? (4)
Sending line (3) the modulation source is set and the FM is
turned on at the same time.
Sending line (4) the instrument returns the FM source. The
instrument sends back the strings INT or EXT (not INTERN
or EXTERN). If the FM is turned off, the string INT is sent
back because the internal source is the default setting for
the command FM:STAT 1 .
:FM:INTern:FREQuency < NUM > (5)
:FM:INTern:FREQuency? (6)
Sending line (5) the frequency of the internal modulation
signal can be changed. The
< NUM > parameter is a NR1 or
NR2 or NR3 number (see paragraph Syntax conventions).
No unit has to follow the number, Hz unit is the default
one. The value is rounded to the resolution.
Sending line (6) the instrument returns the current modula-
tion frequency. The instrument sends back a string repre-
senting a NR3 decimal number.
:FM:INTern:SHAPe SIN | SQU (7)
:FM:INTern:SHAPe? (8)
Sending line (7) the shape of the internal modulation signal
can be changed. The parameters are: SIN for a sine signal,
SQU for square.
Sending line (8) the instrument returns the current shape.
The instrument sends back the same strings as the corres-
ponding command parameters above.
:FM:STATe 0 | OFF | 1 | ON (9)
:FM:STATe? (10)
Sending line (9) the FM can be turned on or off. The FM is
turned on by sending parameters 1 or ON and the parame-
ters 0 or OFF turn the modulation off (if present).
Sending line (10) the instrument returns the current FM
state. The instrument sends back 0, if no FM is in pro-
gress, and 1, if FM is present.
:FM:EXTern:COUPling AC | DC (13)
:FM:EXTern:COUPling? (14)
Sending line (13) the external FM modulation is set to AC
or DC mode.
Sending line (14) the instrument returns the current state.
The instrument sends back the same strings as the corres-
ponding command parameters above.
Example:
FM:INT:FREQ 9E+3; SHAP SIN; DEV 150E+3; STAT ON
6 .15 PM (Phase Modulation)
Commands in order to modify PM parameters
Syntax:
:PM[:DEViation] < NUM > (1)
:PM[:DEViation]? (2)
Sending line (1) the PM deviation can be modified. The
< NUM > parameter is a NR2 number (see paragraph Syn-
tax conven-tions). No unit has to follow the number, the
current unit is the default one. If the value has an accuracy
higher than the resolution, the number is rounded to the
corresponding digit.
Sending line (2) the instrument returns the current PM de-
viation. The instrument sends back a string representing a
NR2 decimal number (without unit).
:PM:UNIT RAD | DEG
(3)
:PM:UNIT? (4)
Sending line (3) the current unit of the phase can be
changed. Two parameters are possible: RAD for radian or
DEG for degree.
Sending line (4) the instrument returns the current unit.
The instrument sends back the same strings as the corres-
ponding command parameters above.
:PM:SOURce INTern | EXTern (5)
:PM:SOURce? (6)
Sending line (5) the modulation source can be selected
and at the same time the PM is turned on.
Sending line (6) the instrument returns the PM source. The
instrument sends back the strings INT or EXT (not INTERN
or EXTERN). If the PM is turned off, the string INT is sent
back because the internal source is the default setting for
the PM:STAT 1 command.
:PM:INTern:FREQuency < NUM > (7)
:PM:INTern:FREQuency? (8)