Introduction Table of Ranges Models 15 and 16 4 Table of Ranges Model 20 6 General Description 8 Limits of Accuracy 10 Design and Construction 12 Range Controls 14 The Movement 16 Scaling 16 Replacement of Internal Cell and Fuse 16 Movement Reverse Control 18 Overload Protection 18 Operation of Instrument 20 Current Measurement 22 Voltage Measurement 22 Resistance Measurement 26 Accessories 30 Conclusion 32 Components List Models 15 and 16 34 Components List Model 20 38 Circuit Diagrams of Avometer Models 15, 16 and 20 42