Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!bloom-beacon!husc6!psuvax1!vu-vlsi!drexel!jeff
From: jeff@drexel.UUCP (Jeff White)
Newsgroups: comp.dcom.modems
Subject: Are MNP modems noiser than non-MNP (also want rec. for some)
Keywords: MNP line noise want recommendations
Message-ID: <636@drexel.UUCP>
Date: 12 Jul 88 15:47:25 GMT
Organization: Drexel University, Phila., Pa.
Lines: 31


  This is actually a two part article.  Our old 1200 baud modems (2 of them)
finally bit the dust on us, so we are in the market for two new modems
(hopefully at least 2400 baud) to replace them.  I would also like to get
a set that are equipped with MNP, if possible.  However, I worked on one
MNP modem before (a Microcom 9624x, the ones that can do 9600 baud), and in
normal (non-MNP) mode, and at any baud rate, they had an absolutely incredible
amount of line noise.  It was almost impossible to get through one line
without an error (or a lot of them) of some kind.  I'm certain it wasn't the
phone line itself, as other modems were used on the line with no problems at
all (and the modem was used on other phone lines were no problems previously
existed).
  My simple theory was that since the MNP software/circuitry was supposed to
virtually eliminate all errros, that the basic modem didn't have to be that
great.  I would like to get MNP, just for the sake of having it for those
that do have similarly equipped modems, but for those who don't, I can't 
afford to have such poor connections in normal mode.
  So, my two questions are:

1. Are all MNP modes pretty inferior in performance and noise rejections when
   operating in non-MNP mode, or was the one modem I worked on just a bad
   example (a lemon)?
2. Any recommendations for 300/1200/2400 baud modems which are reasonably
   priced and have MNP (or, can be upgraded to it at a later date at a 
   reasonable cost)?

  Any help or recommendations would be greatly appreciated.

						Jeff White
						Drexel University - ECE Dept.
						rutgers!bpa!drexel!jeff