8842A
Instruction Manual
5-1.
5-2.
DC Scaling (VDC and mA DC)............................................................................. 5-6
5-3.
Track/Hold Amplifier ............................................................................................ 5-8
5-4.
5-5.
Timing Diagram for One A/D Cycle ..................................................................... 5-10
5-6.
Precision Voltage Reference.................................................................................. 5-11
5-7.
Ohms Current Source............................................................................................. 5-12
5-8.
Ohms Scaling......................................................................................................... 5-14
5-9.
5-10. First Remainder-Store Period ................................................................................ 5-17
5-11. Autozero Period ..................................................................................................... 5-18
5-12. Vacuum Fluorescent Display................................................................................. 5-19
5-13. Digital Controller Block Diagram.......................................................................... 5-20
5-15. Guard Crossing Circuit .......................................................................................... 5-24
5-16. IEEE-488 Interface Block Diagram....................................................................... 5-26
5-17. True RMS AC Option Block Diagram .................................................................. 5-27
5-18. True RMS AC-to-DC Converter............................................................................ 5-28
6-1.
DC Calibration Connections .................................................................................. 6-6
6-2.
First A/D Calibration Prompt................................................................................. 6-11
6-3.
Calibration Functions............................................................................................. 6-12
6-4.
Optimizing Use of the 5450A ................................................................................ 6-20
6-5.
Example A/D Calibration Program........................................................................ 6-25
6-6.
8842A Disassembly ............................................................................................... 6-26
6-7.
Front Panel Disassembly........................................................................................ 6-34
6-8.
6-9.
U202 Pin Diagram ................................................................................................. 6-46
6-12. Typical Dynamic Control Signals.......................................................................... 6-54
6-14. Output of A/D Amplifier (TP101) ......................................................................... 6-59
6-16. Typical Bus Data Line Waveform ......................................................................... 6-60
6-18. Calculating the A/D Reading From TP102 Waveform.......................................... 6-63
6-19. Option -05 Service Position ................................................................................... 6-65
6-20. Option -09 Service Position ................................................................................... 6-68
6-21. Guard Crossing Test Waveforms........................................................................... 6-71
7-1.
8842A Digital Multimeter...................................................................................... 7-6
7-2.
A1 Main PCA ........................................................................................................ 7-13
7-3.
A2 Display PCA .................................................................................................... 7-15
7-4.
Service Centers ...................................................................................................... 7-18
7-4.
Service Centers (cont)............................................................................................ 7-19
805-2. IEEE-488 Interface PCA........................................................................................ 805-8
809-2. True RMS AC PCA ............................................................................................... 809-7
9-1.
9-2.
9-3.
9-4.
Main PCA, Digital ................................................................................................. 9-9
9-5.
Main PCA, Power Supply...................................................................................... 9-11
9-6.
Display PCA .......................................................................................................... 9-13
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