Chuck wrote: > The terminal consisted of a leadscrew-fed printing head with a vertical > typewheel rotating > perpendicular to the (tractor-feed) paper. Said typewheel was in contact > with an ink-soaked felt > wheel. Carriage return was accomplished via a large spring. Utter > steampunk simplicity.
This alphanumeric printer was an extension of the printer internally developed by Friden for its first line of printing electronic calculators, the Friden 115x series. See my online exhibit for one of the 115x calculators, the 1152 at https://oldcalculatormuseum.com/friden1152.html These kind of sucked because of there actually was an intermediate "print wheel inker" drum between the ink-soaked cartridge-loaded ink-source, and the wheel. This intermediate wheel was made of a rubber compound that both A) degraded due to solvent in the ink, and B) degraded due to rubber's usual degradation due to ozone in the atmosphere. In time, this intermediate roller turned into a wad of black, sticky goo that clogged up the works of the printer. I have a number of Friden 115x calculators where this has happened, and replacing that roller is not easy to do, as it's a very precise diameter. I am pretty sure that the alphanumeric version of this printer (which Singer/Friden also sold to OEM customers...not sure if they had many takers) had the same intermediate drum that acted to transfer the ink from the ink roll to the print wheel. In theory, it was kind of a neat design. In practice, it sucked. One thing that was interesting is that the characters on the print wheel were organized in a helical form to help offset the fact that that the carriage motion was constant (it didn't stop when the hammer was fired). The print wheel for an alphanumeric version was larger in diameter to allow for the extra characters beyond those used in a printing calculator.
