Wouter van Ooijen voti.nl> writes: > Depends on what industry you are in. For military and space 10's of > years is no exception. The contract often requires spares to be stocked > or even delivered with the main item(s). You don't have to go that far. Industrial instrumentation, process control, telecom (exchange side of course) and testing and measuring systems all have lifespans of decades. Some 20 years ago major telecom outfits designed shelf cards for PBXes using almost exclusively LM339 and MPSAxxx transistors. It paid off, they are still available after 20 years. There are many examples like this. Just being able to read a drawing or documentation created 15 years ago can be a serious problem, and I have spent many an unpleasant workday tracking down obscure text editors or decoding documentation from dying floppies, which were written using some extinct binary markup text editor under Windows 3.11 or before that. Ditto printed circuit board drawings and schematics. It's more like forensic archeology than electronics. Of course large companies dont give a s**t they just move on to another corporation and tell the customer the product is "discontinued". Some even destroy tooling and documentation due to deals made by pond scum lawyers during corporate takeovers and "program ends". Again, this is not military or secret technology I am talking about. Fortunately many recent developments have moved old documentation into the open, and one hopes that the lessons from the past have been learned and that pond scum lawyers who mandate toolchain destruction and such will be dealt with swiftly in the future. Of course the destruction is not made for fun, it is ordered to ensure that that which was well designed but declared obsolete, does indeed become obsolete by lack of necessary information for maintenance, such that new products can be foisted upon the customer. Peter -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist