BS 6221-21:1984
Superseded
A superseded Standard is one, which is fully replaced by another Standard, which is a new edition of the same Standard.
A superseded Standard is one, which is fully replaced by another Standard, which is a new edition of the same Standard.
Printed wiring boards Guide for the repair of printed wiring boards
Hardcopy , PDF
15-02-2001
English
30-04-1984
Foreword
Committees responsible
Guide
1. Scope
2. Definitions
3. General
4. Special precautions
5. Removal and restoration of protective coatings
6. Component removal and replacement
7. Defective conductors (single- and double-sided
boards)
8. Lifted conductors
9. Lifted and defective lands
10. Eyelet and tubular pin defects
11. Defective plated-through holes (double-sided boards)
12. Base-board material defects
13. Inclusions
14. Short circuits or unwanted conductive material on
the surface of the laminate
15. Repair of inner layers of multilayer printed wiring
boards
16. Repairs to printed edge connectors
17. Modification of assembled printed wiring boards
Appendix
A. Suitable tools and materials
Table
1. Applicability of methods for the repair of defective
conductors
Figures
1. Resistor or capacitor with two axial leads
2. TO5 and TO18 transistors with multi-leads
3. Leaded components where the leads are inaccessible
form the component side
4. Dual in-line package mounted through the board
5. A typical surface mounted dual in-line package
6. Defective conductors
7. Copper foil connections
8. Tinned copper wire connections
9. Insulated wire connections
10. Repair using an insulated wire link
11. Straight conductor repair using parallel gap welding
12. Corner repairs using parallel gap welding
13. Lifted conductors
14. Repair of damaged land using overlaid land
15. Replacement bonded land
16. Lifted land and conductor
17. Eyelet and tubular pin defects
18. Defective plated-through hole
19. Repair of defective plated-through hole by the wire
link method
20. Repair of defective plated-through hole by the
eyelet method
21. Repair of defective plated-through holes by parallel
gap welding: method 1
22. Repair of defective plated-through holes by parallel
gap welding: method 2
23. Damaged base-board materials
24. Printed edge connector: complete contact replacement
25. Removal of unwanted conductors
26. Fitting of additional components and/or wires
27. Modification to printed edge connectors
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