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SCM Cogito 414 Desktop Calculator

Updated 2/12/10

The SCM (Smith Corona Marchant) Cogito 414 is virtually identical to the Cogito 412 with the sole difference being in the number of digits of capacity -- 14 on the 414, and, 12 on the 412. In terms of function and operation, the machines are indentical. The same main circuit board is used in both machines, though different IC's are used in the 414 versus the 412 due to the extra two digits of capacity on the 414. An article in the New York Times dated April 24, 1969, announces the Cogito 414, touting its use of Large Scale IC technolgy as enabling it to be the smallest machine on the market with full calculator functionality.

SCM Cogito 414 Internal View

This particular Cogito 414 I'm guessing was built in the mid-to-late 1972 timeframe, with date codes on IC's ranging from late-1969 through mid-1972. The IC with the '72 date code may be a replacement, in which case, the machine may have been built in mid to late-1970. In cases where there is a skew in the date codes like this (with all but one of the IC's dated in the '69 to '70 timeframe), it is hard to peg the date of manufacture very closely. The IC's on the main board are plugged into Molex-style sockets, so the chips are easily replaced without any evidence left (such as signs of manual soldering). The machine uses a 14-digit, genuine Burroughs, Nixie display, with each tube containing zero through nine and a decimal point.

Cogito 412/414 Keyboard Detail

Internally, the 414 differs a bit from the 412. The 412 uses two daughter boards, each with two LSI IC's soldered onto them which plug into edge card connectors on the main board. The 414 combines the two boards into one, with 4 LSI's on it, but the IC's on the 414's daughter board are different than those on the 412.

Back View with Display Driver Detail

The 414 is only barely detectably slower than the 412, likely due to the extra two digits of calculating that has to occur on each calculation. 9999999999999.9 divided by 1 takes just a shade over 1/2 second to complete.

For more details about the Cogito 414, please refer to the page on the SCM Cogito 412. To see an original ad (scanned black and white to save on image download time), click HERE.


Text and images Copyright ©1997-2011, Rick Bensene.