To make the level change, the tape must run around a tilted idler wheel to steer it to the upper level and around a second tilted idler to level the tape at the reel level. The mechanical engineers had mounted the idlers with a ball and socket arrangement, so they could be tilted to any angle, and attempted to adjust them to obtain the desired operation. Unfortunately they found that when they adjusted one idler, then the second, and returned to the first for a better adjustment, it was farther off than it had been (the successive adjustments never brought them close to a satisfactory tape travel arrangement.) I went back to my Junior College descriptive geometry and determined the angles required so they could drill and mount the idlers and never have to adjust them. It worked without difficulty.
Unfortunately, they ran into another problem: the tape running around the drum became an electrostatic generator that made the tape cling to the drum, so it was difficult to pull around the drum. On simpler equipments this situation can be overcome by having a radioactive material near the tape, but placing such material all around the drum would have been a problem -- I am not certain now that we considered that solution. The tape situation wasn't cleared up until the manufacturers began making the tape slightly conducting to carry off the electricity (early automobile tires had a related problem -- after rolling over the ground on a dry day they would pick up sufficient static electricity to give the unwary person who touched the car a jolt -- it, too, was solved by making the tires slightly conducting, so the charge could leak off).
On to The Data Systems Project Office
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