Larson Davis System 824, Техническое справочное руководство

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9/29/09 FFT (Optional) 12-21
1m/s2 outputs 0.01V then 1m m/s2 will have an output of
0.01mV).
LCAL = 20 log(4.467 nV / 0.01mV) = 20 log(0.4467) = -
7.00dB
LCAL is stored with these steps for instruments that have
firmware version 4.065 or newer:
Press the TOOLS key
Highlight Calibration and press the right arrow key
On the Calibration menu scroll to the bottom of the list and
highlight Advanced
Press the right arrow key to open the Advanced calibration
menu
Highlight the ----Secure---- line and press the check key, this
will change the Cal Level value setting to a special key value
of 224.48 that allow the calibration settings to be entered
directly (the key is to prevent accidental calibration
alteration)
Highlight the CAL Offset setting line and press the check
key
Enter the LCAL value calculated above and press the check
key
Highlight the ----Secure---- line again and press the check
key, this will change the Cal Level value setting back to
114.00 and secure the calibration settings.
Exit the menu by pressing the power key, pressing the left
arrow or pressing TOOLS
For firmware versions prior to 4.065 the calibration offset
(LCAL) is entered using a computer and the following steps.
LCAL is then entered via computer by these I/O commands
using HyperTerminal:
Command: "S1,1"Response: ""// Overall Reset