On Thu, 14 May 2009 06:53:55 -0700 (PDT), snipped-for-privacy@bbs.cpcn.com wrote,
In Southwestern Bell it was always understood that Bell Labs and Western Electric were primarily interested in large multi-office cities where common control capabilities were needed, and [were] not much interested in smaller places where SxS was not only adequate but in many ways superior.
Quite a few cities became all-SxS (starting with Automatic Electric SxS equipment), to their detriment when they grew to really need common control capabilities. Some of those cities were Los Angeles and much of southern California, Houston, Dallas, Oklahoma City, Tulsa and probably many others.
Los Angeles met the need by developing and installing SxS senders. Oklahoma City, when it reached that point, installed an SxS tandem, [because] an engineering study showed an SxS tandem was more economical and just as satisfactory as an XB tandem. Of course, the replacement of all [SxS] offices with (first) #5XB and (later) ESS took care of the problem.
Wes Leatherock snipped-for-privacy@yahoo.com snipped-for-privacy@aol.com