Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 9/27/83; site hplabsb.UUCP Path: utzoo!watmath!clyde!burl!ulysses!harpo!seismo!hao!hplabs!hplabsb!wa From: wa@hplabsb.UUCP (Wayne Ashby) Newsgroups: net.micro Subject: Re: Orphaned Response - (nf) Message-ID: <2179@hplabsb.UUCP> Date: Mon, 19-Mar-84 17:35:21 EST Article-I.D.: hplabsb.2179 Posted: Mon Mar 19 17:35:21 1984 Date-Received: Wed, 21-Mar-84 01:05:46 EST References: <94@haddock.UUCP> Organization: Hewlett Packard Labs, Palo Alto CA Lines: 15 + I don't mean to be petty, but the propagation delay time in a typical wire is likely to be closer to 1.6 to 2.0 ns/ft depending on the type of dielectric material (insulation or pc board material) that is in proximity to the conductive wire. Only with a bare wire in a vacuum will the propagation delay be somewhere close to 1 ns/ft. Also, if you are driving an input device there will always be SOME load (NOT infinite impedance as was stated) however, I agree that it is still advantageous to match the load impedance to the transmission line that is driving it, especially when the driving device has fast rise and fall times and the transmission line is long. My two cents, Wayne ashby (..!hplabs!ashby)