SUM Subsystem Introduction
between the two signals is arbitrary.
l
This command is applicable only with internal sum source (
).
l
You cannot use SUM when DC is the carrier.
l
An arbitrary waveform may not simultaneously be a carrier and a sum waveform.
The following table shows which carriers can be associated with which internal functions.
Modulating Signal
Carrier
Sine
Square
Tri / Ramp
Noise
PRBS
Arb
External
Sine
•
•
•
•
•
•
•
Square/Pulse
•
•
•
•
•
•
•
Triangle/Ramp
•
•
•
•
•
•
•
Gaussian Noise
•
•
•
•
•
•
PRBS
•
•
•
•
•
•
Arbitrary
•
•
•
•
•
•
Sequenced Arbitrary
•
•
•
•
•
•
[SOURce[1|2]:]SUM:SOURce {INTernal|EXTernal}
[SOURce[1|2]:]SUM:SOURce?
Selects source of summing signal.
Parameter
Typical Return
{INTernal|EXTernal}, default INTernal
INT or EXT
Set the sum source to EXTernal:
SUM:SOUR EXT
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
SUM:SOURce EXTernal:
carrier waveform is summed with external waveform. The amplitude and polarity of
the sum signal is determined by the ±5 V signal level on rear-panel
Modulation In
connector. For example, if you
have set the SUM Amplitude to 2.0 Vpp using
, then when EXT signal is at +5 V, the sum signal will
be at 2 Vpp. When the modulating signal is at -5 V, the sum signal will be at full amplitude and opposite polarity.
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Agilent 33500 Series Operating and Service Guide
