Omega Speaker Systems OME-DB-889D 6. Calibration

OME-DB-889D User’s Manual
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6. Calibration
The OME-DB-889D is calibrated to its best of operation. For environment subjected
to large vibrations, recalibration is recommended. Before calibrating the
OME-DB-889D, user should consider having the following available:
z One 6 digital voltage meter
z One temperature meter
z One OME-A-82x series multifunction card
6.1 Calibration VR Description
There are two VRs on the OME-DB-889D.
VR Num. Description
VR1 Amplifier Offset adjustment
VR2 CJC Gain adjustment
6.2 Calibration Steps
1. Turn off computer power.
2. Connect OME-A-822PGL (Or any OME-A-82x series multi-function card) to
OME-DB-889D.
3. Setup OME-DB-889D to default setting
4. Short CH0HI to CH0LO to A.GND of DB889D.
5. Connect probe of voltage meter to CN7 (CJC output: + , A.GND : - ).
6. Turn on computer power
7. Wait about 5 minute (warn up).
8. Run Calibration program of OME-DB-889D.
9. Close the probe of temperature meter to OME-DB-889D them reading
temperature value.
10. Adjust VR1 until the screen value = 0;
11. Adjust VR2 until voltage meter reading value = temperature value X 2.44mV