Stanford Research Systems DS345, Manual

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Modulation and Sweeps
2-14
If no waveform has been downloaded when this modulation is enabled the
message "arb corrupt" will be displayed (see the ARBITRARY MODULATION
section).
WF Single Ramp Triangle Sine Square Arb None
Type
Linear Swp Yes Yes Yes No No No No
Log Swp Yes Yes Yes No No No No
AM No Yes Yes Yes Yes Yes No
FM No Yes Yes Yes Yes Yes No
PM No Yes Yes Yes Yes Yes No
Burst No No No No No No Yes
Table 1: Allowed modulation waveforms for each modulation type
MODULATION RATE
Pressing [RATE] displays and sets the modulation rate. Use the keypad and
unit indicators of Hz, kHz, or MHz (or the MODIFY up/down keys) to set the
modulation rate.
The modulation rate is the frequency of the modulation waveform. For exam-
ple, if the modulation type is AM, the waveform a sine wave, and the rate
1 kHz the modulating waveform will be a 1 kHz sine wave. For sweeps the
modulation rate is the inverse of the sweep time (ie., a 10ms sweep would be
entered as 100 Hz). Burst modulation has no associated modulation rate and
the message "not applic" is displayed if [RATE] is pushed.
The modulation rate has a range of 0.001 Hz to 10 kHz for AM, FM, and PM.
The range for sweeps is 0.001 Hz to 1 kHz (1000s to 0.001s sweep time).
The modulation rate may be set with two digits of resolution. If the modulation
waveform is set to ARB (AM ARB, FM ARB, or PM ARB) the modulation rate
has a different meaning. See the ARBITRARY MODULATION section for
more details.