Hi- Well ADSL really uses the bandwidth available that is not the original telephone bandwidth, i.e. it is broad band with the telephone frequencies deleted. Still damn clever... David Ian McLean wrote: >There is quite a lengthy history behind this. To summarise in a crude >fashion, telephone lines can only really handle about 9600 max. By using >some clever compression and error handling techniques, they increased the >speed to 14.4k, 28.8k and then 33.6k. Then, hitting a barrier with that >technology, by rethinking the problem and using DSP to handle some really >clever compression, they upped the speed again to 56k, which started with >56k flex, and then the very clever V.90. Then, by rethinking the problem >completely again, introduced FFT and cleverer DSP's, and came up with ADSL. >I think this explains why thinks get different after 9600 baud. The guys >who invented these techniques were indeed very clever. > >Rgs >Ian. > > > >>-----Original Message----- >>From: pic microcontroller discussion list >>[mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of James Newton, Host >>Sent: Wednesday, 21 January 2004 11:18 am >>To: PICLIST@MITVMA.MIT.EDU >>Subject: [EE] Why don't baud rates just double? >> >> >>Why is each higher baud rate twice as fast until 14.4K which >>is only 1.5 >>times faster than 9600? >> >>115,200 >> 57,600 >> 28,800 >> 14,400 >> ? >> 9,600 >> 4,800 >> 2,400 >> 1,200 >> 600 >> 300 >> >>--- >>James Newton: PICList webmaster/Admin >>mailto:jamesnewton@piclist.com 1-619-652-0593 phone >>http://www.piclist.com/member/JMN-EFP-786 >>PIC/PICList FAQ: http://www.piclist.com >> >>-- >>http://www.piclist.com#nomail Going offline? Don't AutoReply us! >>email listserv@mitvma.mit.edu with SET PICList DIGEST in the body >> >> > >-- >http://www.piclist.com#nomail Going offline? Don't AutoReply us! >email listserv@mitvma.mit.edu with SET PICList DIGEST in the body > > > -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body