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From: oberman@rogue.llnl.gov
Newsgroups: comp.dcom.lans
Subject: Re: Thinnet cable choices
Message-ID: <1990Nov2.164548.1@rogue.llnl.gov>
Date: 2 Nov 90 23:45:48 GMT
References: <376@dsinet>
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In article <376@dsinet>, marka@dsinet (Mark Anacker) writes:
> 
>     We are about to order a bunch of coax for our ethernets around here, and
> I am faced with a choice of two RG-58A/U cable types.  One the one hand, we have
> Belden 8259, which is the usual black PVC with a NVP of 66%.  The other is
> Belden 8219, which has a cellular polyethylene core and a NVP of 78%.  Since
> these are both 50 ohm cables, it looks like we would get more distance out
> of the second type.  My only fear is that this type of cable is too stiff to
> handle easily.

On thin Ethernet the Vp is not the citical factor. The limiting factor on cable
length is attenuation. I'd look at these numbers (which I don't have handy).
I'd also worry about stiffness as thinnet must be brought to the back of each
system and may get flexed a lot.

To stete the obvious, kinks in coax are NOT good!

					R. Kevin Oberman
					Lawrence Livermore National Laboratory
					Internet: oberman@icdc.llnl.gov
   					(415) 422-6955

Disclaimer: Don't take this too seriously. I just like to improve my typing
and probably don't really know anything useful about anything.