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Re: Note from a satisfied customer

  One fine point.  It may sound picky, but all modem/ISDN transmissions
  are analog.  This phrase of using analog versus digital is simply
  ISDN is simply another form of analog transmission.
  That you cannot hook an analog telephone to the line (as is) simply
  means the analog transmission is different, not digital.
  Let me explain it this way.  If we have a series of 0 and 1 bits,
  and tried to send it "digitally" we would be required to have
  a wave that looks like:
  At each "step" from 0 to 1 we have a transition of a voltage or phase
  angle or whatever that makes a transition in zero time.  This is a
  true digital step function.  But if you check your communications
  handbook you find it takes infinite bandwidth to send a step
  function in zero time.
              W. Curtiss Priest, Director, CITS
        Center for Information, Technology & Society
           466 Pleasant St., Melrose, MA  02176
         Voice: 617-662-4044  BMSLIB@MITVMA.MIT.EDU
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