This is a PDP-8 external bus and data break shielded Mylar interface cable. This cable was cheaper and more flexible than the flat coax cable ( 71K) . DEC recommended using this cable unless the maximum cable length was needed or when connecting free standing cabinets. Only one switch between the Mylar and coax type was allowed.
For the programmed I/O Bus on this cable type the maximum length of all the daisy chained cabling connecting peripherals was 45 feet. For the data break interface the maximum length was 25 feet. The cost in 1970 for a 5 foot cable was $45 versus $90 for the coax. With 11 cables needed for data break peripherals and 6 needed for programmed I/O the cost savings of the Mylar added up.
Feel free to contact me, David Gesswein firstname.lastname@example.org with any questions, comments on the web site, or if you have related equipment, documentation, software etc. you are willing to part with. I am interested in anything PDP-8 related, computers, peripherals used with them, DEC or third party, or documentation.
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