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The components consist of the coax cable and the connector. The cable I use is from Radio Shack and labeled TANDY WIRE AND CABLE E111378A TYPE RG-58U 20 AWG CL2 75 deg (UL). The important thing to remember is that 10Base-2 network segments use Type RG-58 with 50 ohm impedence. It is also a good idea to make a length of test cable and try it out between a couple of computers on the system before actually going through the trouble of pulling cable through wall and ceiling spaces. You dont want to do all that hard work only to find you have got the wrong cabling! The connector itself consists of three parts: the connector itself, the center pin, and the crimp barrel.

Clicking the graphic at left will open a large version of the same graphic in a separate browser window. The illustration is from "Networking Illustrated, The Full-color Guide To How It All Works" published by Que Corporation.

Prepare the end of the cable with the cable stripper tool. Leave yourself a few extra feet of cable length for mistakes. If you get a bad connector, you wll be able to cut it off and try again.

Setting up the cable stripper may require some trial and error adjustment. I have found that not all BNC connectors are created equal - close but not 100 percent. The length of exposed inner insulation band may vary a small amount. 1/8 inch is about right as a starting point (your mileage may vary).

With the type of cable stripper shown, leave about 1/4 inch of cable sticking out the front of the stripper. You then rotate the stripper about the cable until the two layers of insulation and the shielding are cut through to their proper depths.

The stripped cable should look something like this. The center conductor is about 1/2 inch long (it will be cut to fit). The exposed portion of the inner insulation band is about 1/8 inch and the braided shielding between the two insulation bands has been cut back cleanly to the same length as the outer insulation band.

If the cable stripper does not completely do its job, you may have to clean up the cable end with an X-acto knife or needle file. Care counts here. The center conductor should not be nicked, nor should any of the braided shielding be exposed - the most difficult part of this operation is to strip the shielding without damaging the inner insulation band.

Fit the center pin from the connector package over the center conductor as far as it will go. The resulting length of exposed center conductor is the amount of conductor that will have to be cut off for a proper fit. Take the pin back off and cut the center conductor to the correct length with side cutter pliers. It should be 3/16 inch plus or minus. Now when the pin is placed back on the conductor, its base should just reach the inner insulation band (the center conductor should no longer be exposed.)

Place the pin on the center conductor, snug up the the crimping tool over the pin (in the special die portion of the crimper provided for the pin) . . . and when you are absolutely sure everything is properly aligned, crimp the pin to the center conductor. Be careful. If this is messed up, you have to start over preping the cable again with a new connector.

Here is the crimped pin - the base of the pin is seated on the top of the inner insulation band. The crimping process flattens out the pin a bit where the crimping tool applies pressure to it. Clean up any sharp edges left by the crimper with a jewelers file, if necessary.

Slide the Crimp Barrel (or collar) over the cable before installing the connector itself. We will come back to the crimp barrel in the next step, but you have to slide it onto the cable now (you cannot force it over the much larger connector later).

Now comes the real fun . . . NOT!! You must struggle with fitting the connector unto the cable. The knurled cylinder portion fits over the pin and inner insulation band and is press-fitted-twisted-cajoled-cursed into place. It has to fit snuggly between the outer and inner insulation bands, and during the process, it fights with the braided shielding for this tight space.

A REAL Man or Grrrl can do this with their bare hands, but I use the hobby vise for more leverage and control. When you think you have got the connector jammed in under the insulation as far as it will go, jam it a little farther! You will know you are finished when most of the knurled surface has disappeared under ithe insulation and the center pin is rigid in its seated location inside the connector. If the pin is loose and the connector is on as far as it will go, the length of exposed inner insulation band when the cable was stripped is too short. If the pin is tight but a lot of the knurled portion of the connector is still showing, the length of exposed inner insulation band and/or center conductor when the cable was prepared is too long.

We are almost done. Now slide the crimp barrel (placed on the cable at the beginning of the last step) up as close to the connector as you can get it . . . It will take some more profanity and grunting to get as much of it as possible over the bulge in the cable caused by the last step. When you finish it should look something like this.

If you have a general-purpose wire stripper/crimper like the one shown, it has an "ignition terminals" opening that is a little bigger than the cable and a little smaller than the crimp barrel. This is a great tool for putting some leverage behind the crimp barrel when easing it over the bulge in the cable.

Now you can crimp the barrel using the other, larger opening in the BNC crimp tool die. This will tighten and deform the crimp barrel down over the connector and cable for a secure connection.

Crimping the barrel should force the bulge in the cable up over what remains of the exposed knurled portion of the connector to the connectors base. Here is the finished connection. Now you can install another connector on the other end, and then test the completed length of cable. It is good practice to test each length of cable as you go rather than install all the connectors and cabling, and then try to track down a bad connection.