The Internet archive seems to have at least some of https://web.archive.org/web/20190301142501/http://home.earthlink.net/~n1be/pdp11/PDP11.html archived. The most recent archive I could find there is from 1-March-2019. https://web.archive.org/web/20190301142501/http://home.earthlink.net/~n1be/pdp11/PDP11.html -- Ron