SUM Subsystem Introduction
signal will be at the minimum amplitude of -4.8 Vpp. A modulation input of 0 V would result in a signal equal to the
carrier amplitude.
[SOURce[1|2]:]SUM:INTernal:FREQuency {<
frequency
>|MINimum|MAXimum}
[SOURce[1|2]:]SUM:INTernal:FREQuency? [{MINimum|MAXimum}]
Sets the frequency of the summing waveform when internal sum source is selected (
). The
modulating source waveform operates at that frequency, within the frequency limits of that waveform.
Parameter
Typical Return
1 μHz to the maximum allowed for the internal function. Default
100 Hz
+1.000000000000000E-06
The following command sets the summing frequency to 10 kHz on Channel 2:
SOUR2:SUM:INT:FREQ 10000
SOUR2:PHAS:SYNC The following command sets the summing frequency to 1 μHz on Channel 1:
SUM:INT:FREQ MINPHAS:SYNC
l
You can synchronize the phase between the primary signal and the
SUM
signal by sending
after setting the functions for the primary signal and the
SUM
signal. Otherwise, the phase
between the two signals is arbitrary.
l
When you select an arbitrary waveform as the modulating source, the frequency changes to the frequency of the
arbitrary waveform, based on the sample rate and the number of points in the arbitrary waveform.
l
When using an arbitrary waveform for the modulating source, changing this parameter also changes the cached
metadata representing the aribtrary waveform's sample rate. You can also change the modulating frequency of an
arbitrary waveform with
, and
. These commands and the modulation frequency command are directly coupled in order to
keep the arbitrary waveform behaving exactly as it was last played. If you later turn modulation off and select that
same arbitrary waveform as the current function, its sample rate (and corresponding frequency based upon the
number of points) will be the same as it was when played as the modulation source.
l
If the internal function is TRIangle, RAMP, or NRAMp, the maximum frequency limited to 200 kHz. If the internal
function is PRBS, the frequency refers to bit rate and is limited to 50 Mbps.
[SOURce[1|2]:]SUM:INTernal:FUNCtion <
function
>
[SOURce[1|2]:]SUM:INTernal:FUNCtion?
Selects the summing waveform (the waveform added to the primary waveform).
Parameter
Typical Return
{SINusoid|SQUare|RAMP|NRAMp|TRIangle|NOISe|PRBS|ARB},
default SINusoid
SIN, SQU, RAMP, NRAM, TRI, NOIS, PRBS,
or ARB
Select a sine wave as the summing waveform shape for channel 2:
SOUR2:SUM:INT:FUNC SIN
l
You can synchronize the phase between the primary signal and the
SUM
signal by sending
after setting the functions for the primary signal and the
SUM
signal. Otherwise, the phase
Agilent 33500 Series Operating and Service Guide
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