Ametek 7280 Instruction Manual page 65

TIME/STEP
This control defines the time that the oscillator frequency remains at each step of the
complete frequency sweep. The range of available values depends on the setting of
the OPERATING MODE control on the Analog Outputs Menu (section 5.3.18), as
follows:
Operating Mode
FAST
NORMAL
Note that the time per step defined here also applies to oscillator amplitude sweeps -
see section 5.3.11.
ARMED
When this control is set to YES, the frequency sweep is armed. The sweep can then be
started in one of two ways:
a) If the LINK TO CURVE BUFFER control is set to YES then the sweep will be started
at the same time as a curve buffer acquisition starts (see section 5.3.22). This
mode allows the buffer to be used for frequency response measurements, whereby
the response of an external network or system is measured by sweeping the
oscillator frequency while recording the lock-in amplifier's outputs, for example
magnitude and phase. Since the curve buffer can be started using internal or
external triggers, and in the latter case on a per curve or per point basis, there is
considerable flexibility for designing experiments.
In this mode the START control is grayed out as it is inactive.
b) If the LINK TO CURVE BUFFER control is set to NO then the START control above it
is shown in bright text, to indicate that it is active. In this mode, the frequency
sweep is independent of the curve buffer and is operated by pressing the adjacent
key. The control annotation changes depending on whether a sweep is
running, as follows:
START
Pressing the adjacent
changes to PAUSE
STOP
Pressing the adjacent
When a sweep ahs been started and the ARMED control is not shown, the following
two options are also available.
PAUSE
Pressing the adjacent
frequency. The control changes to CONTINUE
CONTINUE
Pressing the adjacent
Chapter 5, FRONT PANEL OPERATION
Time/Step
140 ms to 1000 s in 1 ms increments
1 ms to 1000 s in 1 ms increments
key starts the frequency sweep. The ARMED control
key stops the frequency sweep.
key pauses the frequency sweep at the present
key restarts the paused frequency sweep from the
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