Submitted by Alan Chew
|Tucson FSS (TUS), Arizona, 1966.
The Line Switching Unit (LSU) cabinet can be seen built into the wall.
Each piece of teletypewriter (TTY) equipment was wired to an LSU which
enabled assigning (connecting) it to any TTY circuit. The LSU rack
consisted of mutiple LSU's.
Person is unknown.
Photos home page.