🚀 go-pugleaf

I would be most interested in finding a reference book describing
modems, sorts of technologies used, how they work, over what types of
lines/distances they are designed for, etc. I am also looking for a
good reference on phone line/equipment. For instance, what are the
types of leased lines, what are the technologies involved, how do they work,
what is line conditioning, how does it effect the types of modems you
can run over the line, etc.

I would like something fairly techinical at the level of John
McNamara's "Technical Aspects of Data Communication". His book is a
good start, but doesn't cover modems and phone lines in enough detail
(but then again, it is copyrighted 1977).

Does anyone have a recommendation?

Thanks,
Thomas