BenQ SX930, Service Manual

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Appendix 7 - Thermal and Noise Test Procedure
C.1 Noise Testing Standard
(1) Test Standard : ISO 7779:1999 “Acoustics-Measurement of Airborne Emitted by Information
Technology and Telecommunications Equipment”.
(2) Projector Position: On the center of standard desk.
(3) The background noise level when EUT is not operating should < 19dB.
(4) The sound level meter parameter by setting the following :
Function Setting
Display SPL (sound pressure level)
Frequency Weighting A
(5) Turn on the power of the EUT and allow the system to warm-up for 30 minutes at least.
(6) For the operating mode, Record the highest reading of the sound level meter during the period.
(7) Record values of 4 orientations (Front, Right, Back, Left shown as below picture. These four data
must be measured at the same time.) and then weighting as below formula:
Acoustic Noise Weighting = 10 x log










  
4
10 10 10 10
10 10 10 10
Left Back Right Front
C.2 Exhausted Air Test Procedure:
Exhausted Air<95 oC, measurement position shown as follows: