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940107.txt
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1994-11-13
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Date: Thu, 2 Jun 94 04:30:02 PDT
From: Advanced Amateur Radio Networking Group <tcp-group@ucsd.edu>
Errors-To: TCP-Group-Errors@UCSD.Edu
Reply-To: TCP-Group@UCSD.Edu
Precedence: Bulk
Subject: TCP-Group Digest V94 #107
To: tcp-group-digest
TCP-Group Digest Thu, 2 Jun 94 Volume 94 : Issue 107
Today's Topics:
Digital Communications
Send Replies or notes for publication to: <TCP-Group@UCSD.Edu>.
Subscription requests to <TCP-Group-REQUEST@UCSD.Edu>.
Problems you can't solve otherwise to brian@ucsd.edu.
Archives of past issues of the TCP-Group Digest are available
(by FTP only) from UCSD.Edu in directory "mailarchives".
We trust that readers are intelligent enough to realize that all text
herein consists of personal comments and does not represent the official
policies or positions of any party. Your mileage may vary. So there.
----------------------------------------------------------------------
Date: Wed, 1 Jun 1994 10:53:52 -0500 (CDT)
From: ssampson@sabea-oc.af.mil (Steve Sampson)
Subject: Digital Communications
To: tcp-group@ucsd.edu
> I read a lot of time, papers, RFC, about "Packet Radio" and something the
> author says "digital communication" when i think this is a wrong sentence.
Following a tangent for a minute...
There's an interesting law in the United States which says that there are two
types of modulation. The first is phone the second is data. This little
distinction is what causes a lot of problems when using digitized voice. For
example, if I were to digitize voice, would that be data or phone? The answer
is that it remains phone (digitized phone). Where that becomes a problem is
developing new protocols. TDM (Time Division Multiplex) is authorized for
data from 50 MHz up. TDM for phone is 900 MHz and up. In 1991 I asked for a
Rule Making to allow TDM phone in all places where TDM data was authorized.
RM-7831 was Dismissed in Oct 92 as premature. The FCC said, first you develop
the protocol, then maybe we'll think about it.
> We do (the om's) "Packet Radio". This kind of communication is analog not
> digital so we use a modem ...
Computer data is digital. If you were to hook your microphone up to the TNC
then that would be analog :-) If you were to send digitized audio it wouldn't
be data in America, it would be phone, but it remains "digital communications."
--
Steve
------------------------------
End of TCP-Group Digest V94 #107
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