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From: neal@mnopltd.UUCP
Newsgroups: comp.dcom.modems
Subject: Re: Why do they insist on power cubes???
Message-ID: <162@mnopltd.UUCP>
Date: 7 Jan 91 01:11:38 GMT
Reply-To: gatech!stiatl!mnopltd!neal
Organization: MNOP Ltd., Atlanta, Ga.
Lines: 33
Distribution:


->> 	What began as an annoyance has become a logistic mess. Some years
->> ago, manufacturers of external modems like Hayes moved their power supplies
->> to external power cubes which fit directly into the power line. A small
->> power lead then fed the small, stylish modem. While some (like Prometheus)
->> kept to the internal power supply, most others followed the move to power
->> cubes.
->
->
->The first modem to have its power transformer mounted externally was
->the AT&T DataPhone 1200, also called the model 212 modem.  This was
->the first full-duplex dial-up 1200 bps modem, and was also one of
->the first to be packaged in the new smaller size.
->
->Putting the transformer out side accomplished two purposes:
->
->It reduced the internal temperature of the modem enclosure.  This is
....
->
->It allows a group of modems to be plugged into a rack, rather than
->being mounted in individual enclosures.  A common power supply for
....

It also leaves the vendor with one less detail when going international.  
They can contract the little bricks from a supplier in each country.  (of
course, they are still left with the phone line differences.)

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Neal Rhodes                       MNOP Ltd                     (404)- 972-5430
President                Lilburn (atlanta) GA 30247             Fax:  978-4741
                             emory!mnopltd!neal 
                         gatech!emory!mnopltd!neal 
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