Keithley 2400

Remote calibration .................................................................... 2-16
Remote calibration commands .......................................... 2-16
Remote calibration procedure ........................................... 2-18
Single-range calibration ............................................................ 2-22
3 Routine Maintenance
Introduction ................................................................................ 3-2
Line fuse replacement ................................................................. 3-2
4 Troubleshooting
Introduction ................................................................................ 4-2
Repair considerations ................................................................. 4-2
Power-on self-test ....................................................................... 4-2
Front panel tests .......................................................................... 4-3
KEYS test ............................................................................ 4-3
DISPLAY PATTERNS test ................................................. 4-3
CHAR SET test ................................................................... 4-4
Principles of operation ................................................................ 4-4
Analog circuits .................................................................... 4-4
Power supply ....................................................................... 4-6
Output stage ......................................................................... 4-7
A/D converter ...................................................................... 4-8
Active guard ........................................................................ 4-8
Digital circuitry ................................................................... 4-8
Troubleshooting ........................................................................ 4-10
Display board checks ........................................................ 4-10
Power supply checks ......................................................... 4-10
Digital circuitry checks ..................................................... 4-11
Analog circuitry checks ..................................................... 4-11
Battery replacement .................................................................. 4-12
No comm link error .................................................................. 4-13
5 Disassembly
Introduction ................................................................................ 5-2
Handling and cleaning ................................................................ 5-2
Handling PC boards ............................................................ 5-2
Solder repairs ....................................................................... 5-2
Static sensitive devices ............................................................... 5-3
Assembly drawings .................................................................... 5-3
Case cover removal ..................................................................... 5-4
Analog board removal ................................................................ 5-4
Digital board removal ................................................................. 5-6
Front panel disassembly ............................................................. 5-6