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From: roy@phri.nyu.edu (Roy Smith)
Newsgroups: comp.dcom.lans
Subject: Re: How to terminate a minimal thin ethernet segment?
Message-ID: <1991Apr7.134050.1786@phri.nyu.edu>
Date: 7 Apr 91 13:40:50 GMT
References: <1991Apr5.191653.28927@phri.nyu.edu>
Sender: news@phri.nyu.edu (News System)
Organization: Public Health Research Institute, New York City
Lines: 16

I wrote:
> What I did instead was to just take a 1/8th Watt 51-ohm resistor and
> connect it across the center and shield contacts right on the BNC jack.
> Shouldn't that have been all I needed?

	Several people have already mailed me on this.  What I should have
done was used a 25-ohm resistor (2 50's in parallel; one for each "end" of
the cable).  Assuming a ethernet transmitter is a current source (as was
suggested), having double the resistance put double the voltage on the
cable, which is exactly what you would see in a collision.  I'm embarrassed
that this didn't occur to me when I was doing it.
--
Roy Smith, Public Health Research Institute
455 First Avenue, New York, NY 10016
roy@alanine.phri.nyu.edu -OR- {att,cmcl2,rutgers,hombre}!phri!roy
"Arcane?  Did you say arcane?  It wouldn't be Unix if it wasn't arcane!"