SB>        Thanks, Charles.  That's a bit different from the system I saw
  >        on TV, which relied on an operator to get your number for you.
  >        I'm guessing it was an earlier version of the same system.
  >        Your explanation does raise a couple of questions for me.  How
  >        did individual units identify themselves to the "system" for
  >        billing purposes, and how did individual phones know when it
  >        was them being called?  I know how cellphones do it, but I
  >        don't see how a system lacking a "control channel" could.
           The above is similar to a Marine Radio I had several years
           ago. You stood by on a calling channel (16). If you
           had a call a Marine Operator would hail your boat
           by name and advise you of the call and ask you to go
           to their channel (26). You switched channels and
           she hooked up your call. If you wanted to place a call
           you got on their channel and hailed the Marine Operator
           again using your boat's Name. Supplied her the number
           you wanted to call, and she got them on the line
           and advised you to go ahead. When you finished you
           told her. (to stop the time charges.)€
           First you had to sign up with the company providing
           the service. You supplied them with your phone
           credit card info, to bill any long distance charges.
           There was no monthly charge if you neither placed, nor
           received calls. If you did either, it was $5, minimum.
           The cost was $1 a minute after that. 1 five minute
           call, or 5 one minute calls (or whatever combo)were included
           in the $5 minimum charge.
          I guess if you used it a lot it would have been expensive,
          but I never paid above the minimum charge.
          Of course there was NO privacy, everyone with a Marine
          Radio could eve drop on your calls.
   Email - tomsut@juno.com
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