HP 428B, Operating And Service Manual, Page: 7 / 52

Model 428B
LIST OF TABLES
Table 1-1 Specifications 1
Table 5-1. Recommended Test Equipment. 13
Table 6-1. Replaceable Parts 24
LIST OF ILLUSTRATIONS
Figure 1-1. Model 428B Clip-On Milliammeter 2
Figure 3-1. Measurement Procedures 4
Figure 3-2. Polarity of Current. 6
Figure 3-3. Increasing The Absolute Sensitivity. 7
Figure 4-1. Block Diagram
8
Figure 4-2. Simplified Block. 9
Figure 4-3. Magnetic Mechanical Analogy. 10
Figure 4-5. 428B Flux Gate. 10
Figure 4-4. Basic Flux Gate. 10
Figure 4-6. Waveforms. 10
Figure 4-7. Detector Bridge. 11
Figure 4-8. Negative Feedback 12
Figure 4-9. 90° Phase Shift 12
Figure 5-1. Cleaning Probe Jaws. 14
Figure 5-2. Electrical Zero Set. 14
Figure 5-3. Range Check. 15
Figure 5-4. AC Overload. 16
Figure 5-5. Oscillator Balance Probe. 17
Figure 5-6. Detector Phase Adjustment. 17
Figure 5-7. Detector Phase Display. 18
Figure 5-9. Detailed Troubleshooting Tree. 20
Figure 6-1. Parts Breakdown, current probe. 28
Figure 7-1. Block Diagram. 30
Figure 7-2. Component Locator For Circuit Board Part
No. 00428-66501 31
Figure 7-3. Front Panel Component Locator. 31
Figure 7-4 Rear Panel Component Locator. 31
Figure 7-5. Power Supply. 32
Figure 7-6. Block Diagram. 33
Figure 7-7. Component Locator for Circuit Board Part
No. 00428-66501 34
Figure 7-8. Front Panel Component Locator. 34
Figure 7-9 Rear Panel Component Locator. 34
Figure 7-10. Metering Circuit 35
Figure A-1. 428B Side Views. 37
Figure A-2 Backdating Schematics for 428B 38
Figure A-3 Backdating Schematics for 428B 39