SRS Labs QMS 100 Series, Руководство пользователя

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RGA Command Set 3-63
Technical Reference
RIparam, param: -86.0000 - +86.0000, *, ?, none
Description : RF_Driver output @ 0 amu (Peak Position Tuning command).
JP100 Jumper protected.
Echo: Query Response.
Warning: Please read the Peak Tuning Section of the RGA Tuning Chapter before using this command.
Program the output of the RF_Driver @ 0 amu during a Peak Posion Tuning Procedure. The parameter
(one of four peak tuning parameters) represents the voltage output selected for the RF_Driver @ 0 amu,
in mV.
The magnitude of the RF determines the mass-to-charge ratio of the ions that can pass through a
quadrupole mass filter without striking the rods (i.e with stable oscillations). A linear relationship between
mass and RF amplitude is one of the most attractive features of these type of filters.
The regulated output of the RF source that powers the RGA’s quadrupole rods is controlled by, and
linearly related to, the voltage output of an RF_Driver circuit. A linear relation exists between the output
of the RF_Driver, the RF amplitude on the rods, and the mass setting of the filter. The purpose of a Peak
Position Tuning Procedure is to determine the voltages that the RF Driver must output at 0 and 128 amu
so that all the peaks in an analog spectrum appear in the right position. The RI command is used to
program the voltage output of the RF_Driver @ 0 amu during the Peak Position Tuning Procedure. The
value is saved in the non-volatile memory of the RGA ECU and used by the firmware to generate the
internal scan parameters used to step the RF during scans and single mass measurements .
Note to Supervisors : A calibration disable jumper (JP100) available on the circuit board can be used by
a supervisor to block any attempt to modify the value of the DI parameter. Supervisors may use this
feature to prevent accidental changes in the calibration parameters by inexperienced operators. Setting
JP100 will disable peak tuning of the ECU.
Parameters :
RIparam, param: -86.0000 - +86.0000: If Calibration is enabled by the JP100 jumper (See CE
Command), the parameter is saved into the non-volatile memory of the RGA ECU and the internal scan
parameters used to step the RF during scans and single mass measurements are updated accordingly.
RI* : Use this format to replace the peak tuning parameter with the original factory setting for the
RF_Driver output @ 0 amu. The factory value is retrieved from memory, and used as the new parameter
value to excecute the command as above.
RI? : Query. Returns over RS232 the parameter value currently saved in memory.
RI: Uses the current parameter value to recalculate the internal scan parameters used to step the RF
during scans and single mass measurements. This is often used to compensate against small temperature
drifts in the mass scale, caused by drifts in the output of the RF_Driver.