[ChrisW6ATV]

That's an interesting idea to think about, Andy. I think we could get up to speed relatively quickly on most of the basics like 2x4s for wooden buildings and so on. The real problem is that the sheer size and density of modern human civilizations are fundamentally linked to all the mechanized advances of the last few centuries. The only way such a "back to the Stone Age" re-creation of modern infrastructure could happen is if it was with a relatively small group of people, about the same number as were on Earth at that time originally. Also, differences of opinion and beliefs that are part of human nature mean that a whole new set of wars would still be fought, likely.

Regarding possible sources of new CRT guns, isn't it likely that we could get them made by one or more of the companies in Eastern Europe that still make vacuum tubes for audio and other uses? Also, if these parts deteriorate when exposed to free air, wouldn't sealing them in airtight bags of some kind eliminate most of that problem? I have a friend locally, another amateur radio operator, who is from the Czech Republic and still talks to friends and family there; maybe I should ask him if he can find any contacts in the tube business?