Stanford Research Systems DS335, User Manual

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4-6 Performance Tests
DS335 Synthesized Function Generator
FUNCTIONAL TESTS
These simple tests verify that the DS335's circuitry is functional. They are not intended to verify the DS335's
specifications.
Front Panel Test This test verifies the functionality of the front panel digits, LED's, and buttons.
1) Turn on the DS335 while holding down [FREQ]. Press the [UP ARROW]
and a single segment of the leftmost digit should light.
2) Use [DOWN ARROW] to light each segment (7 of them) and the decimal
point of the left most two digits. Only a single segment should be on at a
time. [UP ARROW] will step backward through the pattern.
3) Push the down arrow key again and all of the segments of all 8 digits
should light.
4) Press the down arrow key repeatedly to light each front panel indicator
LED in turn, top to bottom, left to right. At any time only a single LED
should be on.
5) After all of the LEDs have been lit further pressing of the front panel keys
will display the key code associated with each key. Each key should
have a different keycode.
Internal Self-Tests The internal self tests test the functionality of the DS335 circuitry.
1) Turn on the DS335. The ROM firmware version number, and the serial
number should be displayed for about 3 seconds. The self tests will
execute and the message "TEST PASS" should be displayed. If an error
message appears see the TROUBLESHOOTING section for a
description of the errors.
Sine Wave This procedure visually checks the sine wave output for the correct frequency
and any visible irregularities.
1) Connect the DS335's output to the oscilloscope input and terminate in
50
Ω
.
2) Set the DS335 to sine, 1 MHz, 10 Vpp, and 50
Ω
Load Impedance. Set
the scope to 2 V/div vertical, and .1us/div horizontal.
3) The scope should display a sine wave with one cycle per horizontal
division and about five divisions peak-to-peak. There should be no
visible irregularities in the waveform.
Square Wave This procedure checks the square wave output for frequency, rise time, and
aberrations.
1) Connect the DS335's output to the oscilloscope input and terminate in
50
Ω
.
2) Set the DS335 to square wave, 1 MHz, 10 Vpp, and 50
Ω
Load
Impedance. Set the scope to 2V/div vertical, and 200ns/div horizontal.
3) The scope should show two square waves about 5 division peak-to-
peak.