I bought this on eBay about two years ago, but it has yet to make it onto my website so I thought I'd share it here. This is the Dataphone 9600, a top-end synchronous modem introduced by AT&T in 1975. As implied by its name, its maximum data rate is 9600 baud, basically the fastest long-distance wired data transfer speed possible in 1975. It could run in several multiplexing modes, ranging from one 9600 baud channel up to four 2400 baud channels or any combination in between (7200/2400, 4800/2400/2400, etc.) The modem weighs about 20kg, with a heavy aluminum chassis and card cage construction with a hand-wired backplane. The Dataphone 9600 could only be used on phone lines specially conditioned for high speed data transfer.
The Dataphone 9600 has the dubious distinction of being the only modem known to have killed a person. Your first assumption might be that it fell on somebody's head and killed them with blunt force trauma, but it did in fact poison someone to death. In 1983, Nelly Doris Medina, an employee of the New York Telephone Company, was exposed to dimethylformamimide (DMF) when a Sangamo Weston capacitor in a Dataphone 9600 modem failed. Medina, eight months pregnant at the time, was exposed to DMF venting from the capacitor over a 10-day period, and subsequently died from complications due to toxemia.
They don't make then like that any more. I got my Gimp (the drawing program one, not the one in rubber that I keep in the cellar) out to start drawing a kills tally on the first picture, and then decided that it was bad taste and cancelled it. (Well, that and also because my drawing was crap).