Stanford Research Systems SR620, Руководство пользователя

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Quick Start Instructions 1
SR620 Universal Time Interval Counter
Quick Start
Use this procedure as a quick orientation to
the instrument's features and capabilities. If
you encounter problems, read the detailed
discussions on operation or see the
troubleshooting section.
1) Make sure that the correct line voltage has
been selected on the rear panel power entry
module.
2) With the unit's power switch on "STBY", hold
the "CLR" key in the "DISPLAY" section down
and turn the unit "ON". This will return all of
the instrument settings to their default state.
The message, "SELF TEST PASS" should
briefly appear.
Note : The fan will not run until the unit warms
up. The red LED labeled "CLOCK" in the
CONFIG section may stay on for a few
minutes. The red LED's labeled "START" and
"STOP" may blink if no inputs are applied.
3) Press the MODE down key once to select the
WIDTH mode. Press the source key twice to
select REF ( the 1 kHz REFerence ) as the
signal source. After 1/2 hour warmup, the
display should read 500 us +- 1 ns. If the
displayed value is outside this range see
instructions for running the AUTOCAL
procedure.
4) Press the SAMPLE SIZE up-key five times to
select a sample size of 500. This will slow the
display update rate to 2 Hz, and provide a
more consistent MEAN value.
5) Press the SET key in the DISPLAY section to
set the REL offset to the current value of the
MEAN. The REL LED will turn on and the
display will show a mean value within a few ps
of zero. An 'r' appears on the display to
indicate a relative value.
6) Press the DISPLAY down-key to show each of
the following:
MEAN
0+-100 ps (The REL is set)
REL 500 us +-100 ps
JITTER 5-20 ps
MAX Erratic, but usually <100 ps
MIN Erratic, but usually <100 ps
TRIG +-5 V per the three level knobs
DVM Within 5 mV of zero.
7) Configure an oscilloscope for the X-Y display
mode with the horizontal and vertical inputs
set for dc coupling ( not 50 Ohms ) and 1 V/div
sensitivity. If the scope has scale factor
displays, turn them "off", and set the 20 MHz
bandwidth limit. Center the beam in the middle
of the screen and attach the inputs to the X-Y
display outputs on the rear panel of the
SR620.
8) Press the AUTO key in the SCOPE AND
CHART section to scale the display. If the
DISPLAY REL is set, the HISTOgram of the
pulse widths will be displayed with about 20
ps/div horizontal resolution.
9) In the SCOPE AND CHART section, press the
display button to change from HIST to MEAN.
Press the AUTO button to scale the display.
The scope will now show a 'strip chart' of the
mean values for each set of measurements.
Now select JITTER and press AUTO to
display a 'strip-chart' of standard deviations for
the scope display.