https://vipclubmn.org/Articles/PlatedWire.pdf https://vipclubmn.org/Articles/PlatedWireAddendum.pdf and https://vipclubmn.org/Articles/Wired_Up.pdf The 9300 used it, Donzelli says it wasn't very reliable http://s3data.computerhistory.org/brochures/sperryrand.univac9000.1967.102646204.pdf