I don't have the original standard but if my memory serves me right it was only a recommendation. OCLC shows a bunch of copies at various university libraries around the country. How close are you to a major university?

http://www.worldcat.org/title/interface-between-data-terminal-equipment-and…   might be useful to track down a physical copy of the original document (library search engine - The link above is for the RS-232 spec.) Best regards, David Ritchie On Wednesday, October 30, 2013 4:22 AM, Sergey Lapin <slapinid(a)gmail.com> wrote: Hi, all! Sorry for slightly off-topic question, but do anybody have a copy of original circa 1969 RS232C standard? I need it to resolve conflict with me and my customer regarding if RS-232C REQUIRES the use of DE-25M connector or just RECOMMENDS it? It seems that there is a lot of interpretations of this standard, but no original document anywhere :( I know it might cost $$$, but I will pay all needed fees. All the best, S. _______________________________________________ TUHS mailing list TUHS(a)minnie.tuhs.org https://minnie.tuhs.org/mailman/listinfo/tuhs

Hello! That is a DB-25 Sergei. The 9 pin one that the Newer one uses, is the DE9 So far the others are all correct. ----- Gregg C Levine gregg.drwho8(a)gmail.com "This signature fought the Time Wars, time and again." On Wed, Oct 30, 2013 at 4:21 AM, Sergey Lapin <slapinid(a)gmail.com> wrote: