NS-468 LAN Cable Tester

The NS-468 is a cable tester for checking LAN network cables. It is a 2-in-1 multi-testing tool capable of testing network and phone cables. It has sockets for testing RJ11 and RJ45 modular jack connections and tests for the T568B and T568A wiring schemes. It consists of two parts, the remote and a master. It does not arrive in a box; however, the manufacturer provides a zip case for storage, and a small half-sheet of paper for the instruction manual.

How to use Instructions

The circuit uses a decade counter chip, which tests the condition of each electrical connection and lights a green LED when the connection is good. If you are testing a CAT5 or CAT6 network cable terminated with a RJ45 modular connector, then you connect one end of the wire to the master unit and the other end to the remote unit. Slide the power switch to S for a slow automatic test, where each of the nine LED lights in sequence from 1 to G on both the master and remote units. When an LED fails to light, it indicates a fault with the pin connection associated with it.

When an LED in the sequence does not light, that indicates an open circuit fault. If however, the wrong LED lights, then that is a short circuit fault.

According to the instruction manual, LED 1 through to LED G should light green sequentially on the master unit and on the remote unit, when testing RJ45 connections.

When testing RJ11 connections LED 2, LED 3, and LED 4 should light on the remote unit. If your tester is the version with BNC testing capability, then LED 1 and LED 2 should light.

Master and Remote

For long wires where the ends are less than 1000 ft away from each other, the remote part and the master part are conveniently separable. This is very useful where you have a long network wire that terminates in different rooms.

Power Supply

This tester requires a PP3 9 V battery as the power source. It will last a long time providing you remember to switch OFF the unit after you are done with it.

Review

A cheap cable tester is quite a useful gadget to have when you are building network cables. I have used the NS-468 a few times for testing RJ45 connections on CAT5 and CAT6 patch cables after building them, and it seems to work quite well. I found it very quick and simple to use. I normally prefer to use machine-manufactured cables, however even they can sometimes turn out to be faulty, therefore there are always a couple of these cable testers around the place to check the wiring.

Inside Look

It has a nice simple PCB layout marked with "Peng 0904".

Circuit Design

The main chip is a decade counter. The two transistors that you can see form a bi-stable circuit that generates a clock pulse for the counter IC. It is a simple electronic circuit, which performs well for testing cables.

Buy / Cost

At the time of introduction, I paid four pounds including postage on eBay, and it came all the way from China after three weeks. These same testers are selling for around ten pounds at many online shops today. Of course being an electronic engineer, I could make something like this however, the parts alone would cost far more. I am always amazed to see such cheap gadgets, and always wondering why we here in the UK cannot make it to sell to the rest of the world.

I just love measurement and testing instruments, and with the recession, you can buy quality cable testers at rock-bottom prices. I also have a Velleman VTLAN3, which is another excellent cable tester.