Ribbon cable tester

[MegaloDane]

I just ordered my first custom PC board using your cable-tester.zip! Thanks for your work on the design and the free Gerber files.
I went with JLCPCB for the PC board creation. Minimum order was 5 boards, but with the defaults, it was still under $10, even with shipping. I hope I didn’t pick any incorrect options!
Now to get the boards, and the parts, build and test it. Cool project! Thanks again

[twinturbo]

All the default options are usualy right

[analogoutput]

Except the color which should be purple

[twinturbo]

Indeed , purple is the new red.

[MegaloDane]

I got her working! After I figured out the code!
I tested a 10-conductor Eurorack 10-16 style cable.
Then I made this 16 conductor cable and tested it.

Fun project! Thanks for all the work you put it to it.

[cedrico69310]

hi

can you share your code my build is ok but the result of the tester is wrong.
and i didn’t know how to code…

Br

[analogoutput]

See repo at Richard Holmes / cabletester · GitLab

[Nickoos]

Hello sir! Can you help me with making IDC2x10 tester. I need testing cables for VFDs, but cant find some helpful manual, only on LEDs. I know that I need other miltiplexer and change logic and screen, but I cant do that with my brain.

[analogoutput]

If I were going to do a cable tester over again I might not do it this way. Having a display that says “Cable OK” or “shorted” or “bad cable” with information on which conductor has the problem is kind of cool but really what does anything other than “OK” vs. “Not OK” do for you? If it’s not OK there’s not much you can do about it other than cut off the cable end and put a new connector on and test it again.

In that case just a simple circuit that puts current through LEDs and that fails to light some of the LEDs if there is a short or a break tells you “OK” or “not OK” in a much simpler way.

See:

Simple euro rack cable tester

This seems to be an elegant and simple solution to the problem of checking for continuity and shorts in a self made euro rack cable. You need only a few passive components: [flat_cable_tester_01] It uses only passive components. You connect the DUT (device under test i.e. your self made cable) between SV2 and SV3 (SV1 is for powering the circuit). Given that all LEDs will form a long chain, their summed forward voltages must not exceed the supply’s voltage (he recommends to not use white or b…

[Nickoos]

@Simple euro rack cable tester

It uses only passive components. You connect the DUT (device under test i.e. your self made cable) between SV2 and SV3 (SV1 is for powering the circuit). Given that all LEDs will form a long chain, their summed forward voltages must not exceed the supply’s voltage (he recommends to not use white or blue LEDs). According to the maker: “If there is a break in any of the conductors none of the LEDs will light. If there is a short between conductors the LED between those conductors will not light.”

It is show in detail here:

Thanks for your reply. In fact, you are correct; as a result of testing, we will only see “ok” or “not ok”. I found 2 schemes in russian-language website that can check which conductor has a short circuit or break. One of them is based on logic elements, the second is based on an atmega 8 microcontroller. I can share them here if interested