Stanford Research Systems DS345, Руководство пользователя

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Getting Started
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Introduction
This section is designed to familiarize you with the operation of the DS345
Synthesized Function Generator. The DS345 is a powerful, flexible generator
capable of producing both continuous and modulated waveforms of excep-
tional purity and resolution. The DS345 is also relatively simple to use, the
following examples take the user step by step through some typical uses.
Data Entry
Setting the DS345's operating parameters is done by first pressing the key
with the desired parameter's name on it (FREQ, for example, to set the fre-
quency). Some parameters are labelled above the keys in light gray. To dis-
play these values first press the SHIFT key and then the labelled key.
[SHIFT][SWP CF] for example, displays the sweep center frequency. Values
are changed through the numeric keypad or the MODIFY keys. To enter a
value simply type the new value using the keypad and complete the entry by
hitting one of the UNITS keys. If the entry does not have units, any of the
UNITS keys may be pressed. If an error is made, pressing the CLR key re-
turns the previous value. The current parameter value may also be increased
or decreased with the MODIFY keys. Pressing the UP ARROW key will in-
crease the value by the current step size, while pressing the DOWN ARROW
key will decrease the value by the current step size. If the entered value is
outside of the allowable limits for the parameter the DS345 will beep and dis-
play an error message.
Step Size
Each parameter has an associated step size which may be an exact power
of 10 (1 Hz, 10 Hz or 100 Hz for example), or may be an arbitrary value. If
the step size is an exact power of 10, that digit of the display will flash. Press-
ing [STEP SIZE] displays the step size for the current parameter (the STEP
LED will be lit). Pressing [STEP SIZE] again returns the display to the previ-
ously displayed parameter. The step size may be changed by typing a new
value while the STEP LED is lit. Pressing the MODIFY UP ARROW key while
the step size is displayed increases the step size to the next larger decade,
while pressing the MODIFY DOWN ARROW key will decrease the step size
to the next smaller decade.
CW Function Generation
Our first example demonstrates generating CW waveforms and the DS345's
data entry functions. Connect the front panel FUNCTION output to an oscillo-
scope, terminating the output into 50 ohms. Turn the DS345 on and wait until
the message "TEST PASS" is displayed.
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1) Press [SHIFT][DEFAULTS].
2) Press [AMPL]. Then press [5][Vpp].
3) Press [FUNCTION DOWN ARROW] twice.
4) Press [FREQ] and then [1][0][kHz].
This recalls the DS345's default settings.
Displays the amplitude and sets it to 5 Vpp. The
scope should show a 5 Vpp 1 kHz sine wave.
The function should change to a square wave and
then a triangle wave.
Displays the frequency and sets it to 10 kHz. The
scope should now display a 10 kHz triangle wave.