Device for testing ethernet cables. 4017 - Decade counter step by step lights up the LEDs for checking The cable.

This is a simple ethernet cable tester driven by one integrated circuit. The device uses cmos 4017 - Decade counter. Decade counter step by step lights up the LEDs from LED1 to LED8, at the same time LEDs from LED10 to LED17.

I use blinking LED like clock generator. A LED which has a built-in blinking IC.

 

We need to build two separate small boards:

- a master board whith IC 4017, that will be plugged into one end of the ethernet cable that we need to test,

- a slave board, that will be plugged into the other end of the ethernet cable that we need to test.

 

- If everything is ok, you should see LEDs on the master and slave unit turning on one after other for one second each.

- If there is some broken wire, the corresponding LED on the slave unit will not turn on.

- If there is some inverted wire in the cable, you will see the LEDs turning on not in a sequential order

 

Supply voltage range for cmos 4017 is between 3V to 15V. I use 9V battery.

 

Composents:
- cmos 4017
- 470Ω resistor (17 pieces)
- LED (16 pieces)
- blinking LED
- ethernet plug RJ45 (female) (2 pieces)
- switch
- 9V battery
- wires and two small pieces of single-sided stripboard