Non Intrusive Signal Integrity test?

Projects General Guidance
1

Hello,

I am doing this project where I check if there is a presence of signal in an ethernet cable without connecting the cable to anything. Was wondering if there was any sensor or transducer present that would allow me to just clamp it/ fix it on the cables and hook it to an arduino and extract details.

2

pranavbharadwaj9595:
Hello,

I am doing this project where I check if there is a presence of signal in an ethernet cable without connecting the cable to anything. Was wondering if there was any sensor or transducer present that would allow me to just clamp it/ fix it on the cables and hook it to an arduino and extract details.

First question, why do you want to this ?

Second, what type of Ethernet cable ?

Third, what do you mean exactly by 'Signal Integrity" ?

Fourth, what 'details' do you want to extract ?

3

If there's a current, there's an electric field which you can detect. That's about it what you can do without making electrical connections to the wires in your cable.

4

Problem is there is a signal and a return in the cable so I suspect any net current in the cable is zero , so no external field . The cables are twisted pair too , designed to stop this effect .

5

A small flux change can still be detected.
But your best bet is still inserting a pass-through connector and hijacking the signal traffic,,, but this increases your probability of being detected/arrested/shot.

6

Of course, forgot about that part.
The zero net current shouldn't be a problem (after all currents in power cables are routinely measured through their field), the twisting part may indeed make it quite a bit worse.

7

Currents in power cables are measured using one lead only, with the exception of ground fault detectors.

8

wvmarle:
the twisting part may indeed make it quite a bit worse.

If its twisted pair ethernet cable then very likely.

At the limit, even the electronics at the end of a twisted pair ethernet cable, which has full access to the differential signals within (if that is the cables the OP has in mind) will struggle to decode.

However the OP has not owned up to exactly what it is they want to do, but the mention of 'integrity' implies checking from the outside of a cable that what ever is happening inside the cable is valid and coherent such that both ends of the cable are decoding the MAC layer correctly.

The chances of that are ...........................................