Cable Tester v1.0 (it's so bad)

A project log for Audio cable tester

The evolution of an XLR / Jack audio cable tester

borazsloborazslo 04/06/2017 at 20:270 Comments

The very fist version of the cable tester is very simple: four switches with four LEDs. When the cable connected you can switch on/off the buttons and the LEDs bright up if the line has connection. That seems simple and perfect. But ...


3d Printed Box:

And the final and working product:

So it works just fine. When I connect the XLR cable I can check to connectivity of the 3 main lines/pins and the chassis ground.

Mismatched cables

But what does this circuit do when some cables are connected but in a wrong way? Sometimes it works just fine (left picture), but in other cases it makes false OK signs (right picture). So it is time to make a better version of the circuit.