AC40 Service Manual
Selecting TDH39 headset
Select "Transducer Setup" (Figure 2)
Select "Headset phone" to select TDH39 headset
Enter the serial numbers for the left and right phones in the field "Left" and "Right"
Calibration of TDH39
Equipment needed for TDH39 calibration:
Measuring amplifier
Acoustical IEC 60318-3 (IEC 303) coupler
Frequency counter
Correction values for coupler
Figure 2
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