Following up a message from Dave Shiner to Jonathan Hunter:
MB> JH> I've got three Arcnet cards (SMC) lying around here, that
MB> JH> I'm itching to play with - just for fun :-)
MB> JH> What kind of cabling do they need? The physical connection
MB> JH> on the cards themselves are BNC plugs (exactly the same as
MB> JH> 10Base-2), but I have heard that they need 100 ohm cable or
MB> JH> something similar??
 DS> For 3 stations you'll need what is known as a "passive hub".
 DS>  It's  basically 4 93ohm resisters w/one lead soldered
 DS> together to form an X  shape and the other leads each go to
 DS> the center conductor of a BNC  female end.  Then connect all
 DS> the BNC shells together (usually in a  metal box) and you
 DS> have a hub. Looks like this:
 DS>  --------------------------
 DS>  |                        | 
 DS> BNC--^93ohm^-\ /-^93ohm--BNC
 DS>  |            X           |
 DS> BNC--^93Ohm--/ \-^93ohm--BNC
 DS>  |                        |
 DS>  --------------------------  <---Square Metal Box
 DS> You can hook up 4 stations to this, for more than 4 you're
 DS> supposed to  buy an "active hub".  At that point I would
 DS> replace everything w/10baseT  Ethernet!  It should work
 DS> w/any coax for short distances.
It's important not to think of ARCnet in Ethernet terms.  You do not actually 
need a hub for this, but could simply tie all of the nodes together onto a 
single coax bus.  ARCnet can be wired in various star and bus topologies, and 
in all sorts of combinations.
 
-- Mike
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