Summary

• Perform four different continuity tests at once
• Check for copper pour shorts on new PCBs
• Easily test cable pinouts

Have you ever been using a continuity tester and wanted slightly more from it? Maybe you want to check a number of things at once - perhaps see what pads on a new PCB are attached to VCC, ground, or other signals? Maybe trace the pinout of an unusual cable? This product may be for you.

What Is It?

It's like having four continuity testers at once. A common probe has an LED mounted on it, which lights up in one of four colours to indicate which of the other connections it has continuity with. One of these other connections is a yellow handheld probe, the other three are handy test clips to attach to a PCB, plug or socket pins, or anything else you are testing. Touching the black probe to an unknown pin will show which, if any, of the identifying clips it is connected to. If there's no connection, it glows a dull purple colour. In case of a short between identifying clips, the LED will flash a cycle between the colours that are shorted.

This product is a self-contained tester, just add 5V DC via the 2.1mm connector jack. Supplied with the tester is a convenient USB-to-2.1mm cable, so any spare USB port or PSU/charger should suffice.

Using It To Test New PCBs

This tester makes it easy to check for power- or ground-plane shorts on newly-fabricated PCBs, while also checking connectivity between all the pads that should be connected. Just attach the red and green clips to a handy VCC and ground hole (any connector mounting hole within about 6mm of the board edge should accept these), and the LED will flash between red and green if there's a VCC-to-ground short. Hopefully there won't be, so now you can start using the LED and yellow probe to check continuity between other sets of pads or holes on the board, lighting yellow when there's a connection between the two pads you're touching. The LED will also light red or green when you probe a pad connected to VCC or ground. It's like having three testers at once.

But wait - there's even more. The third blue identifying clip works just like the others; so if you have a large net that's shared among many pads, you might find it convenient to test for that at the same time.

This test procedure is best on a brand-new PCB without any components populated. The presence of things like power decoupling capacitors across the power lines may confuse the identifying pulses used to detect which line is which, so be careful not to let any other passive or active components get in the way.