Thanks BOAC, got it in the last alternative
The input cable from the phone line to the 'pooter' was dead

. However, I had used two other cables, so, presumably, they must have been u/s also

Am inputting this from a Tiscali dial-up connection, newly made; still can't make a connection with Orange and I suspect that they are having problems as my partner's dial-up with them is also not responding.
GTW, thanks also; I appreciate that allowing the ISPs to shovel their software onto one's machine is to be avoided if possible, but, for we simpletons, working from their CDs is NORMALLY the most straightforward option. I like the idea of D-I-Y signing up ... is there a muppet's guide to the procedure somewhere?
Now to finding a RELIABLE, EFFICIENT, UK based tech support ISP for broadband

if such a thing exists

This is for me. of course. The problem with the neighbour's machine remains unsolved for the moment.