Rion NC-74, Инструкция по эксплуатации

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11
Reference
Sound level meter and sound measurement system calibration
value
When performing acoustic calibration with this unit for a sound level
meter or a sound measurement system using a sound fi eld type micro-
phone, make the adjustment so that the meter or the device reading is
as shown in the calibration value tables (Table 1 and 2). These values
were derived taking into consideration the relationship between the
sound pressure level at the microphone in the coupler (specifi ed sound
pressure level) and the infl uence of case refl ections and the microphone
refraction effect when placed in a sound fi eld.
Example
For the sound level meter NL-21, the calibration value as shown in
Table 1 is 93.9 dB. Set the NC-74 to the microphone and adjust the
NL-21 so that it reads 93.9 dB. (See the illustration at right.)
30 120 EXT Cal
ON OFF
PUSH