Table of Contentss
Chapter 1: Intro & Specifications ...........................................1
Introduction ........................................................1
1.1 Acoustical Outputs ...............................................1
1.2 Telecoil Outputs .................................................2
1.3 Battery Current ..................................................2
1.4 Digital Readout of Sound Pressure Level ..............................2
1.5 Measurement Inputs ..............................................2
1.6 Harmonic Distortion Analyzer ......................................3
1.7 Available Tests...................................................3
1.8 Input Power .....................................................3
1.9 Physical Dimensions..............................................3
1.10 Printer, Internal ..................................................3
1.11 Printer, External .................................................4
1.12 Internal Sound Chamber Dimensions ................................4
1.13 Operating Temperature ............................................4
1.14 Guarantee ......................................................4
Chapter 2: Specification Test Procedure .....................................5
2.1 Source Frequency Accuracy ........................................5
2.2 Source Harmonic Distortion........................................5
2.3 Source Amplitude Accuracy after Leveling ............................5
2.4 Attenuator Accuracy ..............................................6
2.5 Accuracy of Coupler Measurement ..................................6
2.6 System Equivalent Input Noise .....................................7
2.7 Crosstalk .......................................................7
Chapter 3: Calibration...................................................11
3.1 Introduction ...................................................11
3.2 Hardware Calibration ............................................11
3.3 System Calibration ..............................................12
3.4 Microphone Check ..............................................12
3.5 Microphone Calibration ..........................................16
3.6 Insert Earphone Calibration .......................................20
Chapter 4: Circuit Description ............................................25
4.1 System Overview ...............................................25
4.2 CPU ..........................................................26
4.3 CPLD .........................................................28
4.4 Signal Source ..................................................32
4.5 External Microphone Adapter Board ............................35
4.6 Microphone Prescaler ............................................35
4.7 Power Supply ..................................................39
