The Morkrum Company Model 12 Type-Bar Page Printer was the first commercially-viable
machine, and was produced for twenty years, before being replaced by the M15.
The Model 12 used commercial typewriter sub-assemblies: typewriter manufacturers L.C. Smith and Woodstock contributed the platen and type-basket components. The Printer was of the moving-platen type, and always seemed to have problems with paper feeding. The Roll of paper was hung at the rear, and the "web" of paper coming off it was passed down under a "guide bar" to strip it from the roll and steer it up to the constantly moving carriage. Separate motors powered the typing Unit and the Distributor Unit that was used for Start-Stop service. The Typing Unit contained latching relays that accepted signals from the Start-Stop or a Multiplex Receiving Distributor. A Power supply for furnishing DC to the Set circuits occupies the shelf under the table top. 
The M12 had two distributors. The Sending Distributor is the familiar Cam-and-Contacts type. So is the Receiving Distributor, but instead of being closed for the full length of its code pulse, a contact closes only briefly during the center of the pulse interval, thus making the selection at the most reliable point. 
The Model 12 was produced from 1922 to 1925 under the Morkrum Company, from 1925 to 1929 under Morkrum-Kleinschmidt, and from 1929 to 1943 under Teletype Corp. However, the M12 may have carried a "Teletype" nameplate and the scroll symbol as early as 1921.
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Standard Model: 12
|The Model 12 was a work-horse.|