Stanford Research Systems SR620, Руководство пользователя

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22 Configuration Menus
SR620 Universal Time Interval Counter
Now use the CONFIG section to setup the scan.
Press the "SEL" key to select the "Scn" menu.
Press the "SET" key and use the SCOPE AND
CHART up/down keys to setup the scan
parameters as follows:
Scan Configuration Menu for Example
Line Display Function
1
ScAn EnA rEPEAt Enable repeated scans
2 ScAn PtS 250 Set 250 points per scan
3 hoLd 0.01 S Set minimum hold time
4
dA Src chrt chrt DefaultbD/A functions
5 dA --.--- --..--- Can’t set D/A voltages
6 Step -.--- -.--- Not stepping D/A’s
7 dELAy ScAn ScAn Enable delay scans
8 gAtE-StEP 1E-6 1 us gate width & step
9 StArt 0.000001 Start scan delay at 1 us
Then press the "RESET" key in the SAMPLE SIZE
section to exit from the CONFIG menus.The
SR620 will compose a scope display showing the
frequency of the VCO as a function of time after
the rising edge of the REF OUT. If the oscillator
stops, then the scan will stop. The "AUTO" key in
the SCOPE AND CHART section may be used to
scale the scope display, and the "PRINT" key may
be use to generate hardcopy.
The strip chart of the
mean for the time scan is
shown here.
A pulse of 100 us
duration, delayed by 100
us from the EXT trigger,
was applied to the VCO
input of an RC oscillator.
The scan shows the
transient frequency
response of the oscillator.
The cursor indicates a
frequency of 77.34203
kHz at 210 us after the
EXT trigger input.