Stanford Research Systems DS345, Manual

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Performance Tests
5-8
3) Set the DS345 to 1.002 MHz, and the spectrum analyzer to 501 kHz.
Measure and record the amplitude of the 501 kHz carrier. It should be less
that -26.02 dBm.
4) Repeat step 3 with the DS345 and spectrum analyzer set to the following
frequencies: 10.002 MHz and 5.001 MHz, 20.002 MHz and 10.001 MHz, and
30.002 MHz and 15.001 MHz. Record the results and verify that the carrier
levels are below -26.02 dBm.
SPURIOUS SIGNALS
These tests measure the spurious signals on the DS345's sine wave outputs.
They check both close-in and wide band spurs.
specification: < - 45 dBc at full output
1) Connect the DS345 to the RF spectrum analyzer. Set the DS345 to sine
wave, +23.98dBm (10Vpp), 0V offset.
2) Set the DS345 to 26.662 MHz. Set the spectrum analyzer to 26.662 MHz
center frequency, 100 kHz span. Measure the amplitude of the spurious sig-
nals and verify that they are < -50 dBc.
3) Set the DS345 to 20.004 MHz. Set the spectrum analyzer to 20.004 MHz,
100 kHz span. Measure the amplitude of the spurious signals and verify that
they are < -50 dBc.
4) Set the DS345 to 18 MHz. Set the spectrum analyzer to sweep from 1kHz
to 100 MHz. Ignoring the harmonics of the fundamental at 36MHz, 54 MHz,
72 MHz, and 90 MHz, measure the amplitude of the spurious signals and
verify that they are < -50 dBc.
HARMONIC DISTORTION
This test measures the DS345's sine wave harmonic distortion.
specification: < -55 dBc, frequency < 100 kHz
< -45 dBc, frequency 0.1 to 1 MHz
< -35 dBc, frequency 1 to 10 MHz
< -25 dBc, frequency 10 to 30 MHz
1) Connect the DS345 output to the FFT analyzer input with a 50
Ω
termina-
tor. Set the DS345 to sine wave, 100Hz, 1 Vpp.
2) Adjust the FFT analyzer to view the fundamental and its harmonics. Verify
that all harmonics are below -55 dBc.
3) Repeat step 3 at 1 kHz and 10 kHz.
4) Connect the DS345 output to the RF spectrum analyzer input. Set the
DS345 to 50 kHz. Verify that the harmonics are at least -55 dBc.
5) Set the DS345 to 500 kHz, 5 MHz, 15 MHz, and 30 MHz and verify that all
harmonics are at least -45 dBc, -35 dBc, -25 dBc, and -25 dBc respectively.
Record the results.