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Are you planning an article on making coax/thinwire
Ethernet cables?
The best advice I can give you is to buy or make (see below)
CAT 5 or 5E cables. Unless you have a lot experience making coax cables and
use the correct cable, connectors, and tools and avoid playing "musical
chairs" (moving stuff around a lot), the network cabling will be simpler
and more reliable with twisted-pair cable and RJ-45 connectors. You will
also be able to upgrade the network to 100BASE-T with new adapters in the
future. In particular, if you play games, 100BASE-T is what you will eventually
want.
Most problems with thinwire coax are caused by using the wrong wire and/or
connectors and not properly installing the connectors. Cable used for cable
television is RG-59 or RG-6. It usually has a solid-wire core and a characteristic
impedance of 75 ohms. It is the wrong cable to use for a thinwire Ethernet.
A thinwire Ethernet cable is made from RG-58A/U. It has a stranded core and
a characteristic impedance of 50 Ohms. The best connector is is two-piece connector,
AIM (http://www.aim-electronics.com/)
catalog #27-9200. I don't recommend any other combination. If you need to meet
plenum standards use twisted-pair. You need a good stripper, designed for thinwire.
I use(d) one made by Prestige (Stark #639; http://www.starkelectronic.com/czp18a.htm#STRIP. It
includes instructions. You will also need a good crimper and, again, lots of
practice... It would be quite a chore to write an article on how to make thinwire
cables and they are obsolete.
In a two-computer, thinwire network, the cable cannot be directly connected
to the NICs (Network Interface Cards). Tee connectors are connected to
the NICs and the cable is connected to the Tees. 50 ohm terminators must be
connected to the Tees at the very ends of the network. One of the terminators
should be grounded. The other terminator should not be grounded. If both ends
are grounded, a dangerous ground loop condition can exist from a lightning
strike. However, the network will probably work OK if neither end is grounded…
For instructions on making twisted-pair cables see How
to Make Your Own CAT5 Twisted-Pair Network Cables.
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