George Fliger wrote in a message to Mike Bilow:
 LM> Arcnet is 75ohm and only 2mbits.
 MB> ARCnet is nominally 100 ohms.
 GF> More accurately it is 93 ohms.
The cable is 93 ohms, because that is the closest standard coax you can get 
to 100 ohms.  However, the official design impedance of ARCnet is 100 ohms.  
Of course, anything within 10% tolerance will work without any trouble.
 
-- Mike
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