Stanford Research Systems DS345, Руководство пользователя

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Getting Started
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5) Press [MODIFY UP ARROW].
6) Press [STEP SIZE].
7) Press [1][2][3][Hz]. Then press [STEP SIZE].
8) Press [MODIFY DOWN ARROW].
9) Press [STEP SIZE] then [MODIFY UP ARROW]
10) Press [STEP SIZE].
11) Press [MODIFY UP ARROW].
The frequency will increment to 10.1 kHz. The
flashing digit indicates a step size of 100 Hz.
Observe that the step size is indeed 100 Hz. The
STEP LED should be on.
We've changed the step size to 123 Hz and dis-
played the output frequency again.
The frequency is decreased by 123 Hz to
9977 Hz.
The step size is displayed and is increased from
123 Hz to the next larger decade–1 kHz.
The frequency is displayed again. The flashing
digit indicates that the step size is 1 kHz.
The frequency is incremented to 10.977 kHz.
Frequency Sweep
The next example sets up a linear frequency sweep with markers. The
DS345 can sweep the output frequency of any function over any range of al-
lowable output frequencies. There are no restrictions on minimum or maxi-
mum sweep span. The sweep time may range from 1 ms to 1000 s. The
DS345 also has two independent rear-panel markers that may be used indi-
cate specific frequencies in the sweep. The MARKER output goes high at the
start marker position and low at the stop marker position.
An oscilloscope that can display three channels is required. Attach the
FUNCTION output BNC to the oscilloscope, terminating the output into 50
ohms. Set the scope to 2V/div. Attach the SWEEP rear-panel BNC to the
scope and set it to 2V/div. The scope should be set to trigger on the falling
edge of this signal. Attach the MARKER rear-panel BNC to the scope's third
channel. This signal will have TTL levels.
1) Press [SHIFT][DEFAULTS].
2) Press [AMPL] then [5][Vpp].
3) Press [SWEEP MODE UP ARROW] twice.
4) Press [RATE] then [1][0][0][Hz].
5) Press [START FREQ] then [1][0][0][kHz].
This recalls the DS345's default settings.
Set the amplitude to 5Vpp.
Set the modulation type to linear sweep.
Set the sweep rate to 100 Hz. The sweep will take
10 ms (1/100Hz). Set the scope time base to
1ms/div.
Set the sweep start frequency to 100 kHz.