If I recall correctly the later voice of SP detectors was Majel Barrett-Rodenbary of Star Trek fame. She played Nurse Chapel and was the voice of the computer in all of the Star Trek series.
[
en.wikipedia.org] or www.imdb.com/name/nm0000854/
Dr Zarkoff, Your close in that she played the mother of Counselor Troi.
Majel also did a lot of other voices for automated phone systems.
Ray Eiser