Grounding a thinnet setup?

Grounding a thinnet setup?

Post by Scott Kriefa » Tue, 04 Jul 1995 04:00:00



I've recently installed WD8013 NICs in my two systems at home.  They
are connected via thinnet/coax, and are currently being used only
with Linux (and not very often at present).

I know very little about Ethernet networking, and recently discovered
that one end of the thinnet run should be grounded.  I have a 50 Ohm
terminator with ground connector, but am unsure what the ground connector
should be connected to.  Any advice?

Could this lack of grounding account for the poor performance I have
seen? (~150KB/sec during FTP tranfers between the two machines)

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Scott Kriefall
Mankato, MN   USA

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Grounding a thinnet setup?

Post by Cameron L. Spitz » Tue, 04 Jul 1995 04:00:00




>I've recently installed WD8013 NICs in my two systems at home.  They
>are connected via thinnet/coax
>I know very little about Ethernet networking, and recently discovered
>that one end of the thinnet run should be grounded.

Nobody has told me a good reason to ground the coax to anything.
If the adapter is any good, it will have a spark gap and a 1 megohm
resistor between the Thinnet shield and the logic ground in the PC.
A lower value resistor would allow unwanted currents and degrade the
signal to noise ratio on the wire.

Quote:>  I have a 50 Ohm
>terminator with ground connector, but am unsure what the ground connector
>should be connected to.  Any advice?

Tie it to the cable so it doesn't get tangled or short something,
or just cut it off.

Quote:>Could this lack of grounding account for the poor performance I have
>seen? (~150KB/sec during FTP tranfers between the two machines)

I doubt it.  Either the systems are really slow or the cable is wrong.
Have you got 50 ohm terminators on both ends of the segment?
Is the segment a straight line or did you try to make a Y someplace?
No branching is allowed and both ends must be terminated.

Cameron
http://www.rahul.net/cameron

 
 
 

Grounding a thinnet setup?

Post by John K Turn » Wed, 05 Jul 1995 04:00:00



>I know very little about Ethernet networking, and recently discovered
>that one end of the thinnet run should be grounded.  I have a 50 Ohm
>terminator with ground connector, but am unsure what the ground connector
>should be connected to.  Any advice?

It certainly won't hurt anything to ground the terminator.  You can
connect it to the AC ground on an outlet if you are sure the outlet if
properly grounded.

                                BDH