Stanford Research Systems DS345, Руководство пользователя

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Performance Tests
5-5
PERFORMANCE TESTS
These tests are intended to measure the DS345's conformance to its published specifications. The test re-
sults may be recorded on the test sheet at the end of this section. Allow the DS345 at least 1/2 hour to warm
up, run the DS345's autocal procedure, and proceed with the tests.
FREQUENCY ACCURACY
This test measures the accuracy of the DS345's frequency. If the frequency
is out of specification the DS345's timebase frequency should be adjusted
(see CALIBRATION section).
specification: ± 5 ppm of selected frequency
1) Turn the DS345 on and allow it to warm up for at least 1/2 hour. Set the
DS345 for sine wave, 10 MHz, 1 Vpp.
2) Attach the output of the DS345 to the frequency counter. Terminate into
50
Ω
. Attach the reference frequency input of the counter to the frequency
standard. Set the counter for a 1s frequency measurement.
3) The counter should read 10MHz ± 50Hz. Record the result.
AMPLITUDE ACCURACY
The following tests measure the accuracy of the DS345 output amplitude.
There are separate tests for sine, square, and ramp/triangle. The tests
measure the accuracy of the amplitude as a function of frequency. The sine
wave test also measures the performance of the attenuators. There is only a
single test for triangle and ramp functions because they have the same sig-
nal path.
Frequency < 100 kHz
Connect the DS345 output to the voltmeter through the 50
Ω
terminator. After
the DS345 has had at least 1/2 hour to warm up, run the autocal procedure.
Then perform the following tests.
Sine Wave
specification: ±0.2 dB (±2.3%), amplitude > 5V
±0.3 dB (±3.4%), amplitude < 5V
1) Set the DS345 to sine wave, 100Hz, 3.54 Vrms (10Vpp).
2) Read the AC voltage on the voltmeter. Repeat at 1kHz and 10kHz, and
100 kHz. The readings should be between 3.459 and 3.621 Vrms (± 2.3%).
Record the results.
3) Set the DS345 to 1 kHz. Set the amplitude to 1 Vrms. Read the voltmeter
and record the results. The amplitude should be between 0.966 and 1.034
Vrms. Repeat at 0.5 Vrms, 0.25 Vrms, 125 mVrms, 75 mVrms, 40 mVrms,
and 25 mVrms. Record the results. They should be within ±3.4% of the set
values.