Re: A comment in an earlier post that "Another customer was very suspicious when I told him the same thing that the modular jack was universal".
Modular jacks have been "universal" only since the FCC ruled against "protective connecting arrangements" in 1976. AT&T/Bell then developed the modular jack (RJ-11, RJ-45 etc.) as we currently know them. They were standardized under FCC Rules Part 68, and a few of them have been standardized internationally. My house was built in
1974 and it has the old-style 4-prong plugs - about the size of a golf ball. I suspect that there are still hundreds of thousands of homes that either have no telephone jack at all (telephone hard-wired to a wall connector or "C block") or have the 4-prong plugs like mine. Where 4-prong plugs were used a separate outboard ringer was hard-wired to the phone line so a ring could be heard even if all of the phone sets were unplugged.I bought 4-prong to modular adapter plugs at first (which they still sell), but now I've re-wired everything with RJ-11s.
In a related note, my house did not have an "network interface box" until about five years ago. The phone line came in through a carbon-block protector. The telco guy insisted that I "must" have one and didn't believe me until I took him around to the back and showed him the phone line with no NIB.
Regards.
Charles G. Gray Senior Lecturer, Telecommunications Oklahoma State University - Tulsa (918) 594-8433
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