Trident Tether Cable Troubleshooting

Greetings all, I am seeking a good approach for locating and then repairing an electrical discontinuity in my 100 meter Trident tether line. Given the dive related stresses these lines encounter, surely others have encountered this issue.

  • How can I rule out connection issues at the terminal ends?
  • How does one find an open break in the cable (hopefully) without affecting its integrity?
  • How to splice and restore these cables after removing any damaged sections?

Thanks in advance,

Hi Howard,

I wish I could help. I have never had any issues with my tether. My only suggestion is using a multimeter on the tether. If you have one with alligator clips, you can clip them on the contact points and go down the tether flexing it slightly either way. If you had a connection you might find if it breaks the connection or makes a connection that was not there before. There is a setting on some multimeters where it does a beep when there is a connection. That way you do not have to look at the meter to see if it makes or breaks the connection.

Hope that helps a bit.

Many thanks for your reply and suggestion. Flexing the tether along its length to test for the circuit break with multimeter connected - That’s a very good idea for isolating the problem and will try it this weekend.
It is great that you have avoided tether issues so far, esp. given your extensive dive record.

We deployed Trident last year in a stream to aid CAL Trout and DFWS in monitoring for trout habitat restoration. Performed well in the deeper pools, but took a beating in shallow, rocky, fast-moving runs.
I’ll be sure to share any results.
Thanks again for being in touch.

I think the way telephone people test cables is by injecting a signal into the wire, then using a separate tool which lights-up when that signal is seen; if you know anyone with such a thing, running along the cable length with the tool should indicate the exact break point.

A “low tech” way to do the same thing might be to use an old AM radio, if you can think of something to connect the faulty wire onto that would inject a signal into it (e.g. one pole of an AC 12volt transformer - if you can find an AC one lying around) then run the radio along the wire until the hum changes at the break.

Do you have a multimeter with a capacitor test function? If yes - a third idea might be to test the capacitance of both ends of the faulty wire - which might give you a ratio of where along the wire to expect the break (e.g. same = middle, 25% one end and 75% other end means the break is 1/4 way along…)

Thanks for the informed response. Based upon your ideas and Michael’s suggestion I’ve contacted a friend with a capacitance test function on his multimeter. Also sorting through a box of old gear (we all have one, right?) for an old portable radio. If the capacitance test can get me in the ballpark, bending the cable along this shorter section is much easier and should let me pinpoint the break.