Use the DC output of a sound level meter. When DC output voltage of full scale is 2.5 V and 10 dB is 0.5 V, the setting of the DS-0221 is as follows;

1. Input coupling: DC
2. Unit for unit calibration: dB
3. Click [Analysis] > [Calculate Equation Set] in this order of the menu, and input the formula "Time*20+50" in DISP1, when the range of the sound level meter is 100 dB.

Input the formula [TIME*20+50] in DISP1, when the range of the sound level meter is 90 dB.
Input the formula [TIME*20+30] in DISP1, when the range of the sound level meter is 80 dB.
From the above settings, the sound level will be displayed in the screen 1.