cmoore@brl.mil (VLD/VMB) (08/14/89)
Some of the addresses and phone numbers I have observed include "TWX 510 xxx-xxxx" where the x's are in the same style as our 7 digit phone numbers. Is this use of 510 affected by the upcoming use of 510 as an area code? (Earlier notes in this Digest said that 510 will be formed c. 1991 by splitting the east bay area -- Oakland etc. -- off from area 415 in California.) Speaking of 415/510 split, what area code will Marin County, which gets the north end of Golden Gate bridge, end up in? I assume San Francisco and south to area 408 will stay in 415. [Moderator's Note: 410-510-610-710-810-910 as 'area codes' came of course from the days when Bell was operating the TWX network. 410-510 were roughly the east coast of the US and New England. 610 was, and is Canada. 710 was the southern United States, and 910 was everything from Chicago westward. 810 was Mexico. I don't think Western Union has assigned anything new in 410-510 for years. In fact 410 is virtually empty. They seem to have taken a fancy to 910 for assignment of email addresses on EasyLink, and they seem to be using more traditional telex style numbers for other other applications. I don't think you will see much of 510 as a TWX area code after the next couple of years. And even with the little overlapping of 510-voice and 510-TWX which does occur, I'll venture a guess there will be even less overlapping of prefixes. PT]