Audio Visual Custom cable tester

XLSERVICE

New Member
This is my first solo Picaxe project (hardware and software).

The idea was originally for a basic BNC cable tester, but the specification grew and grew until it eventually turned into a multi input / output tester for the majority of cables used in the Event ProAV hire business.

The tester uses a 40X1 Picaxe to give 10 input and 10 output test pins. Pinouts of the various cable types are entered into the software along with their names to give a description of the cable under test on the LCD screen.

The test procedure has two tests. The first is a continuity test to determine the cable type and its instantaneous continuity. If passed, the next test is the 'Wiggle' test where all output ports are powered up for 10 seconds and the inputs monitored for intermittent contacts. Bright green and red LEDs give a second visual display pass or fail.

The LCD screen has a serial backpack as it only needs 1 valuable Picaxe pin. The screen is turned off and on using a pulse relay when the tester falls asleep after 15 seconds on inactivity.

The tester has been in daily use for several months now and is proving very reliable.


Future improvements would be:

Use rechargeable batteries and re-charge the batteries when the mains is plugged in.

Get the battery monitor working properly by using the DC-DC converter to power the Picaxe as well as the LCD. The current DC-DC is not powerful enough to drive both LCD and Picaxe.

Locate the LCD commands on the EPROM to free up some space....


Thanks for looking, comments and suggestions welcomed.
Cheers
Alan
 

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Andrew Cowan

Senior Member
Much neater wiring than I was expecting for such a project.

How do you tell it what cable you are testing? Does it detect it? A very nice project!

A
 

XLSERVICE

New Member
Cheers Andrew

I was planning to create a PCB for the next one, but as Im leaving the company shortly Im not going to get around to it.

The cable type is detected from the number of pins and their connections. It does mean that a faulty cable sometimes register as good cable of another type, however, the screen tells you what cable it thinks it is.

Connectors with the same number of pins are spread across the 10 ports to differentiate them.

Alan
 
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