Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site brl-tgr.ARPA Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!ihnp4!zehntel!hplabs!hao!seismo!brl-tgr!jcp From: jcp@brl-tgr.ARPA (Joe Pistritto) Newsgroups: net.dcom Subject: Re: Noisy {{~r lines affecting 212A { modems Message-ID: <7438@brl-tgr.ARPA> Date: Wed, 16-Jan-85 19:37:23 EST Article-I.D.: brl-tgr.7438 Posted: Wed Jan 16 19:37:23 1985 Date-Received: Mon, 21-Jan-85 03:47:48 EST References: <145@pttesac.UUCP> Reply-To: jcp@brl-tgr.ARPA (Joe Pistritto ) Organization: Ballistic Research Lab Lines: 15 The errors you get with the 212A modem are almost all burst errors, caused by the scrambler/descrambler circuit in the modem. When any bit is damaged, because of the scrambled nature of the signal, (which is scrambled in 'groups' of bits (I think 4)), all of the bits in the group are damaged, typically turning into ones, hence the high probability of characters with lots of ones in them (RUBOUT 0177, Tilde 0176, } 0175. This is one of the worst features of the 212 design, and renders it practically useless for interactive lines except where line quality is better than average. Try VADIC 3400 protocol modems if you can, they don't have this problem (or many others for that matter...) -JCP- PS: I don't work for VADIC, I just like their stuff.