Modify Function; Modify Function Type; Modify Function On/Off; Modify Function Parameters - Stanford Research Systems DS360 Operating Manual And Programming Reference

Modify Function

This section describes how to set the modify functions on the DS360, including sweeps, bursts and
bandwidth limited noise.

Modify Function Type

Modify functions are associated with the different output functions. Only the options
available for the currently selected function type are accessible in the MODIFY FUNC
list. Sweeps are available for sine and square waves; bursts are available for sines,
squares, white and pink noise; bandwidth limited noise is available for white noise only.
No modify functions are active for 2-Tones. Press the [∧] up or [∨] down keys in the
MODIFY FUNC area until the desired selection is lit. If you cannot select the desired
type of modify function, verify that the selected function type allows that modify
function type.

Modify Function On/Off

To activate or deactivate the currently selected modification, press the [ON/OFF] key in
the MODIFY FUNC area. The SWP/BURST LED is lit to indicate that the
modification function is active.

Modify Function Parameters

The parameters for modify functions can be entered whether the function is currently
active or not. Only modify parameters (START FREQ, STOP FREQ ...) that are valid for
the selected modify function can be changed. If a currently invalid modify parameter is
selected, the unit will beep and display "not APPL" (not applicable). If a function type
change causes the currently displayed modify function to become invalid, the display
will revert to the frequency display.

Sweeps

Frequency sweeps are active for sine and square waves. Sweeps are increasing in
frequency and can be linear or logarithmic in nature. Frequency changes during the
sweep are phase continuous, including the wrap around from stop to start frequency. The
rate can be set from 0.1 Hz to 3.1 kHz, with 2 digits of resolution. Sweeps can be
continuous, externally triggered or singly triggered. The DS360 has a Sweep output on
the rear panel that can be used to synchronize an oscilloscope or other external device to
the DS360 sweep output. Use the MODIFY FUNC [ON/OFF] key to begin or end
sweeping.
Note
Sweeps have an amplitude rise at the wrap around point (stop frequency to start
frequency transition) due to ringing in the reconstruction filter. The effect is minimal for
stop frequencies below about 130 kHz. If high stop frequencies and large output
amplitudes (>30 Vpp, unbalanced) are used, it is possible to cause the output to clip. To
DS360 Ultra Low Distortion Function Generator
Operation 3-11