Instruction manual

Calibration

5. Press the CAL key. A calibration screen such as shown below ap-

pears.

Verify the “Acoustic Calibration” is displayed in the upper part of

the screen.

If “Internal Calibration” is shown in the upper part of the screen, press

the DISPLAY key. The calibration mode will change to “Acoustic

Calibration”.

6. Use the

keys to adjust the reading of the NL-42/NL-52 to the

value shown below.

NL-42: 93.9 dB

NL-52: 94.0 dB

7. Press the CAL key. The measurement screen returns.

8. Turn off the Sound Calibrator NC-74 and the NL-42/NL-52.

9. Remove the microphone very carefully and slowly from the cou-

pler.

Note

For details on the Sound Calibrator NC-74, refer to

the documentation of that product.