Agilent Technologies 6674A

Post-Repair Calibration .....................................................................................................................................................63
When Required...............................................................................................................................................................63
Inhibit Calibration Jumper..............................................................................................................................................63
Calibration Password......................................................................................................................................................63
Restoring Factory Calibration Constants........................................................................................................................63
EEPROM Initialization......................................................................................................................................................64
Transferring Calibration Constants To Factory Preset Locations .....................................................................................64
Disassembly Procedures....................................................................................................................................................69
Top Cover.......................................................................................................................................................................69
RFI Shield.......................................................................................................................................................................69
Front Panel Assembly.....................................................................................................................................................70
S1 Line Switch................................................................................................................................................................70
A1 Front Panel Board.....................................................................................................................................................70
A1DSP1 LCD Display....................................................................................................................................................70
A1G1 and A1G2 Rotary Controls ..................................................................................................................................70
A1KPD Keypad..............................................................................................................................................................71
Rear Panel and/or A2 GPIB or Isolator Board ...............................................................................................................71
Output Subchassis...........................................................................................................................................................71
A5 Control Board ...........................................................................................................................................................71
A6 Output Filter Board...................................................................................................................................................72
A7 Snubber Board and D900 Output Rectifier...............................................................................................................72
T900 Output Power Transformer/L900 Output Choke...................................................................................................72
AC Input Filter................................................................................................................................................................72
A3 FET Board and Heatsink Assembly..........................................................................................................................73
A4 AC Input Board.........................................................................................................................................................74
B1 Fan ............................................................................................................................................................................74
Principles of Operation.........................................................................................................................................................77
Introduction .......................................................................................................................................................................77
INTERFACE CONTROL CIRCUITS..............................................................................................................................77
A2 GPIB Board (667xA Series Only)............................................................................................................................77
A2 Isolator Board Circuits (657xA Series Only)............................................................................................................78
A1 Front Panel Assembly...............................................................................................................................................78
A5 Control Board ...........................................................................................................................................................79
Secondary Interface .....................................................................................................................................................79
CV/CC Control............................................................................................................................................................80
Switching/Downprogramming Control .......................................................................................................................80
Power Circuits...................................................................................................................................................................81
A4 AC Input Board.........................................................................................................................................................81
Input Filter and Rectifier..............................................................................................................................................81
Bias Supplies and Bias Detect ..................................................................................................
...................................81
Fan Speed Control
..............................................................................................................
.........................................81
A3 FET Board ................................................................................................................................................................82
Output Circuits ...............................................................................................................................................................82
Replaceable Parts..................................................................................................................................................................85
INTRODUCTION.............................................................................................................................................................85
Chapter Organization......................................................................................................................................................85
Reading the Tables .........................................................................................................................................................85
How To Order Parts ..........................................................................................................................................................86
Diagrams..............................................................................................................................................................................117
Introduction .....................................................................................................................................................................117
Chapter Organization.......................................................................................................................................................117
General Schematic Notes.................................................................................................................................................123
Backdating...........................................................................................................................................................................145
Index.....................................................................................................................................................................................155