Robert Ragen Comparing Friden 1151 Board with Equivalent Friden 130 Electronics
This photo is clipped from an advertisement published by Texas Instruments in 1968 touting their development of TTL Medium Scale Integrated Circuits for Friden to match the functionality of the transistorized five-stage switch-tail ring counters used in the earlier Friden 130 counting circuitry. These IC's were used to significantly shrink the size of the Friden 1160-series CRT-display calculators (Friden 1160, Friden 1162, and the Friden 1166); as well as being used in Friden's first printing electronic calculator, the Friden 1150. The photo shows Friden's Chief Calculator Architect, Robert Ragen, holding a circuit board from the Friden 1151 (a simple programmable version of the 1150) circuit board containing the three Texas Instruments IC-based counter chips along with the pair of transistoized circuit boards from the Friden 130 that represent approximately the same circuitry as implemented on the significantly smaller IC-based board. It appears the photo was taken at one of Friden's 115x-series assembly line locations.