The voltages must remain the same in order to be
compatible with old
equipment per government regulations. Believe it or not there are still
many people out there with old (ancient) rotary dial telephones.
a) Don't forget about these pseudo modern phones - keys, but
still emiting pulse scemes.
b) I had, until I switched to ISDN, still a 1927 Telephone
in every day use. Worked fine, even with the latest (analogue)
exchange :) - Noy I connect it via an a/b adaptor.
Gruss
H.
--
Ich denke, also bin ich, also gut
HRK