I've seen this episode dozens of times now, but had never noticed the pile of cannibalized radio cabinets in the corner of Kirk and Spock's room, until tonight. It makes sense, of course, new electronic components were expensive, so I can see the guys doing a little after hours dumpster diving to scrounge up parts for Spock's frame grabber, which had grown in size to fill almost the entire room by the end of the episode.
I'm going with the theory that Kirk, Spock and McCoy were always in 1930 New York for those few weeks, and were always part of what was going to happen, the same as in Assignment Earth.
I'm going with the theory that Kirk, Spock and McCoy were always in 1930 New York for those few weeks, and were always part of what was going to happen, the same as in Assignment Earth.