Fluke 9640A Series, Инструкция по эксплуатации

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Local Operation
Operating the Instrument
3
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Table 3-19. Sweep Preferences Fields
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Field Preference
Type
[1]
Linear Range, Linear Span, Log Range, Log span
Mode [2]
Single, Repetitive
Squelch
Enable, Disable
Trigger Type
[3]
Output, Input, Disable
Trigger Edge
[4]
Rising, Falling
Prog. Bar Units
%, As Range
[1] Linear and Logarithmic sweeps – Step size between discrete frequencies is either constant (linear) or logarithmic.
[1] Range or Span – A Range is presented in terms of a Start and Stop Frequency. Span is an alternative presentation in the form of
Center and Span. The latter tends to be used in very narrow span applications around a center frequency (e.g. Sweep a bandpass
filter). These inputs are transparently converted to Start and Stop values and are bound at this point.
[2] Single or Repetitive - Like an oscilloscope on single shot or repetitive sweep.
[3] Enabled or Disabled – When enabled, Squelch is active between all frequency transitions. When disabled, Squelch is active only at
hardware range boundaries.
[4] Disable, Output or Input. Typically, Trigger is “disabled”. This allows the Sweep to run repetitively or as a single shot when prompted
(Start Sweep key), without accounting for a trigger. Output configures the rear panel BNC to generate a trigger waveform at the start of each
sweep. This trigger waveform can be used to trigger an equivalent sweep in either a Spectrum Analyzer or an Oscilloscope. The action of
sweep remains unaltered. Input configures the rear panel BNC as an input; the Start Sweep is now to “arm” the trigger. The system will now
wait for a trigger at the rear input, before commencing the sweep. This “armed” state is indicated on the Status Bar. Once initiated by a trigger,
the behavior of the Sweep (pausing, stopping, continuing) is un-altered. This feature allows the Instrument sweep to be synchronized with
another instrument.
Note
Trigger Output and Input are Software Trigger features; timing accuracy is typically better than ±1 ms. The trigger
output pulse is delayed by typically 14 to 16 ms from the sweep start to ensure the output signal is settled at the trigger
point.
[5] Rising or Falling defines the edge polarity generated as a trigger Output or that triggers in the case of Input.