Stanford Research Systems DS345, Manual

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Performance Tests
5-3
vertical, and 200ns/div horizontal.
3) The scope should show two square waves about 5 division peak-to-peak.
4) Increase the scope sensitivity to 1V/div and measure the size of the over-
shoot at the beginning of the square wave. It should be less than 0.5V peak-
to-peak.
5) Adjust the scope to 2 V/div and 5ns/div. Measure the 10% to 90% rise
time of the square wave. It should be less than 15ns.
Amplitude Flatness
This test provides a visual indication of the sine wave amplitude flatness.
1) Connect the DS345's output to the oscilloscope input and terminate in
50
Ω
.
2) Set the DS345 to sine wave, 10Vpp. Modulation to linear sweep with a
sawtooth waveform. Set the start frequency to 1Hz, stop frequency to
30MHz, and the rate to 100Hz. Turn the DS345's sweep ON.
3) Set the scope to 2V/div vertical, and 1ms/div horizontal. Trigger the scope
on the falling edge of the DS345's SWEEP output.
4) The scope should show a sweep that is essentially flat. The peak-to-peak
variations should be less than ±3.3%. Ignore any dc variations, using the
peak-to-peak measurements for flatness comparison.
Output Level
This test provides a visual check of the DS345's output level control.
1) Connect the DS345's output to the oscilloscope input and terminate in
50
Ω
.
2) Set the DS345 to sine wave, 1MHz, 10Vpp. Set the scope to 2V/div verti-
cal and 1
µ
s/div horizontal.
3) Verify that the DS345's output is about 10V pk-to-pk.
4) Set the DS345 to 5Vpp verify the output.
5) repeat step 4 at 1Vpp, 0.5 Vpp, 0.1 Vpp, and 0.05 Vpp. Adjust the scope
as necessary.
This completes the functional tests