We designed and built a device that will test the basic integrity of a straight through or crossover cable. All you have to do is plug the cable into the two ends of the box. The X LED will light if the cable tests OK for a crossover cable. The S LED will light if the cable tests OK as a straight-through cable. You don’t have to change anything to test the next cable, just plug it in. It makes it really easy to go through a stack of cables and sort them out. Here is the completed unit with a straight-through cable plugged in:
Notice that the S LED is on. The LED next to the switch is simply a power indicator.
Since there is a lot involved in this project that our readers may not be familiar with, we will write a series of articles and go through each step of the design and construction of this device in detail. We will start with a general run-down of Category 5 cables, then design a circuit that will test the cable, emulate the circuit to work out the bugs, design a PC board, etch and tin the PC board, and finally assemble all of the pieces together.
There are five parts to this article:
Build Your Own Cat5 Cable Tester – Introduction