The Sciences/Library Computer station actually remained fairly consistent throughout all three seasons of regular production episodes and hardly changed at all.
Regarding the little rows of rocker switches, from the first regular production episode (“Corbomite Maneuver”) to the last one (“Turnabout Intruder”) the Sciences/Library Computer station has always had three rows of rocker switches. There are two rows, one above the other, just below the large “speaker” (which later also becomes the self-destruct display). These two rows of rocker switches are below the users left hand, just to the left of the station’s centerline. There is also a third row of rocker switches just to the right of the station’s centerline. Here’s a shot from “Charlie X” where you can see all three rows—the two rows off to the left, one above the other and the third row off to the right, under Mister Spock's hand:
These rocker switches were still in place in “Turnabout Intruder:”
Something that did change was the addition of a single column of five white pushbuttons, just to the right of the hooded viewer below the blue intercom. The column of pushbuttons was not present in “Charlie X” but was added to the bridge set during the next episode “Balance of Terror.” Here’s a shot of this new column of white pushbuttons.
Folks may remember that as Mister Spock hoisted himself up off the floor after doing some work under the access panel of his station, he inadvertently placed his hand on the bottommost button of this column, giving the
Enterprise’s position away to the Romulans. It was because of this very scene that the buttons needed to be added to the station very close to the station’s edge--so that Spock could accidentally activate the switch according to the script’s needs.
All that being said, the old Mike McMaster bridge blueprints—reverse engineered by microscopic study of 16 mm filmclips before the era of VCRs much less DVDs—are right on the money. They accurately show the buttons on the Sciences/Library Computer station as they existed at the end of the Third Season.
I think what Al says is true: the bridge panels are not entirely accurate from how the bridge was last seen in “Turnabout Intruder,” claims of using the original blueprints and meticulous evaluation of screen shots notwithstanding. The sets aren’t perfect and we can always improve.
Here’s a shot from “World Enough and Time” that exhibits the exact deficiencies Al indicates: the column of five white pushbuttons next to the hooded viewer is
not present, the two rows of rocker switches just to the left of the centerline of the station (below the “speaker”) are
not present and the row of rocker switches to the right of the centerline of the station is
not present.
As Al indicated, we’re working on rebuilding the bridge from scratch. No doubt such omissions will be corrected when the set upgrade is complete.
Greg Schnitzer
Gaithersburg, Maryland
