Ametek 7280 Instruction Manual page 68

Chapter 5, FRONT PANEL OPERATION
5-22
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 5.3.12
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 linearity measurements, whereby the
response of an external network or system is measured by sweeping the oscillator
amplitude 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 amplitude
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
amplitude. The control changes to CONTINUE
Time/Step
140 ms to 1000 s in 1 ms increments
1 ms to 1000 s in 1 ms increments
key starts the amplitude sweep. The ARMED control
key stops the amplitude sweep.
key pauses the amplitude sweep at the present