Specifications

Vectors On/Off
One of the most fundamental choices you must make about your display is
whether to draw vectors between the samples, or simply let the samples fill in
the waveform. To some degree, this is a matter of personal preference, but it
also depends on the waveform.
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Having vectors on slows the display of the oscilloscope. This works
better for slower sweep speeds, peak detect or average displays, and
signals with stable triggers.
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Having vectors off works better for fast sweep speeds, normal displays,
or unstable triggers. Complex analog signals like video and eye
diagrams show more intensity information with vectors off.
One of the benefits of the HP 54645A/D is that you can change display modes
after you acquire data. You can turn vectors on and off, or switch from peak
detect to normal display modes. If you acquire data in normal mode, then
switch to peak detect, you will see all the peaks in memory. You are not
guaranteed, however, of seeing every 5-ns peak.
Digital channels on the HP 54645D are not affected by the display menu.
They are always displayed with peak detect and vectors on. They also only
contain one trigger worth of information.
Vectors On considerations
When using single shot or when using pan and zoom, and data has been
acquired at 200 Ms/s, Vectors On uses a modified sinx/x digital filter to connect
samples. This filter gives the oscilloscope a single-shot bandwidth of 50 MHz
(1/4th of the sample rate.) The memory depth of the HP 54645A/D gives you this
sample rate at single-shot sweep speeds of 200 us/divison and faster.
For data sampled slower than 200 Ms/s with Vectors On, simple linear
connection of the samples is used.
MegaZoom Concepts
Display Modes
4-16