Tabor Electronics 5064, Руководство пользователя

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3
Using the Instrument
3-27
in to reconstruct the waveform. The technique of generating sine
waves above certain frequency is not within the scope of this
manual however, one should remember that above certain
frequency the waveform is loosing purity and quality because the
number of points that are available to construct the waveform are
inversely proportional to the output frequency. This statement is
true for all standard waveforms and this is the reason for limiting the
upper frequency of certain waveforms.
There are certain menus that provide access to sine waveform
parameters; These are:
Frequency
– programs the frequency of the sine waveform. Note
that at low frequencies (up to about 200 kHz), when you modify the
frequency parameter, the output responds with coherent change
however, at higher frequencies, the waveform has to be re-
computed every time and therefore, when you modify the
frequency, the output wanders until the waveform is being re-
computed and then restored to full accuracy.
Amplitude
– programs the amplitude of the output waveform. Note
that amplitude and offsets can be programmed freely within the
specified amplitude window, as explained in the Programming
Amplitude and Offset section in this chapter. Note that setting the
amplitude parameter in this menu overrides amplitude setting in all
other menus.
Offset
– programs the offset of the output waveform. Note that
offset and amplitude can be programmed freely within the specified
amplitude window, as explained in the Programming Amplitude and
Offset section in this chapter. Note that setting the offset parameter
in this menu overrides offset setting in all other menus.
Phase
– sets the start phase of the output waveform. You will not
be able to see any change in the waveform if you generate a
continuous sine waveform however, if you place the generator in
triggered run mode, the output will start the sine wave generation
from a point defined by the Phase parameter. The start phase is
programmed in units of degree.
Reset Parameters
– Resets the sine wave parameters to their
original factory defaults.
Square Wave
The square waveform is a commonly used waveform. The
waveform is generated from a lookup table that has 1000 points
and therefore, the square waveform is generated with 1000-points
accuracy up to about frequency setting of 200 kHz (output
frequency = sample clock frequency / number of points). As
frequency is increased above 200 kHz the number of points is being
reduced automatically.
There are certain menus that provide access to square waveform