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[Derrick Sonnenberg]

Good day.

Our company uses DT-12 for our sub-snake runs, with lenghts from 10' to 75' and 12 channel boxes with female inputs.

I've noticed, these runs and/or boxes seem to be introducing a fair bit of noise to our system. A quick test in the shop confirms this. After checking into 5 or so trunks, I have two observations:
A. every cable has at least 5, sometimes 10 or more, connectors that do not show continuity with a multi-meter.
B. the resistance i'm measuring varies greatly, anywhere from .6 Ohms to 150 Ohms.

I'm not the best at this game yet, my question is as follows:

How easy is it to remove the locking heads from these trunks to take a look at?
Is the varied resistance from broken solder points, at the head of the trunk? or is there a larger issue I'm not seeing, internally.

Still waiting for a call back from the rep, so I thought I'd try the internet.

Please point me in the right direction if I don't make sense!

Thank you for taking the time.

Cheers

[Riley Casey]

Any open circuits or any measurement much more than the resistance between the meter probes is a red flag BUT testing multi-pin connectors reliably with a multimeter is problematic in itself.  Only reliable way is to find a loose pin and socket, solder those to a couple of wires and test the actual mated connection.  Then if you have bad lines you can have confidence that it's not a poor connection to the probe and move ahead with repair solder connections OR just boot them and go with crimped connections.  Far more reliable in my experience.  Been a while since I've had to deal with DT12s but if I remember correctly the back shell  just unthreads from the connector face after removing the gland nut on the cable clamp.  Might be a lock screw or two.  If you do find open circuits then you have to get into the solder side and measure at the ends of the wires to confirm that the wire is broken as opposed to a broken pin/socket.  Almost always a wire broken in the cable though if there is no visible break in the back shell.

[Derrick Sonnenberg]

Any open circuits or any measurement much more than the resistance between the meter probes is a red flag BUT testing multi-pin connectors reliably with a multimeter is problematic in itself.  Only reliable way is to find a loose pin and socket, solder those to a couple of wires and test the actual mated connection.  Then if you have bad lines you can have confidence that it's not a poor connection to the probe and move ahead with repair solder connections OR just boot them and go with crimped connections.  Far more reliable in my experience.  Been a while since I've had to deal with DT12s but if I remember correctly the back shell  just unthreads from the connector face after removing the gland nut on the cable clamp.  Might be a lock screw or two.  If you do find open circuits then you have to get into the solder side and measure at the ends of the wires to confirm that the wire is broken as opposed to a broken pin/socket.  Almost always a wire broken in the cable though if there is no visible break in the back shell.

thank you Riley, a helpful summation.

Cheers

[Jeff cech]

There are DT12 cable analyzer/testers available from broadcast supply houses (Markertek for  example). They are spendy but make fast work of testing lots of cable. Good luck,

 T

Good day.

Our company uses DT-12 for our sub-snake runs, with lenghts from 10' to 75' and 12 channel boxes with female inputs.

I've noticed, these runs and/or boxes seem to be introducing a fair bit of noise to our system. A quick test in the shop confirms this. After checking into 5 or so trunks, I have two observations:
A. every cable has at least 5, sometimes 10 or more, connectors that do not show continuity with a multi-meter.
B. the resistance i'm measuring varies greatly, anywhere from .6 Ohms to 150 Ohms.

I'm not the best at this game yet, my question is as follows:

How easy is it to remove the locking heads from these trunks to take a look at?
Is the varied resistance from broken solder points, at the head of the trunk? or is there a larger issue I'm not seeing, internally.

Still waiting for a call back from the rep, so I thought I'd try the internet.

Please point me in the right direction if I don't make sense!

Thank you for taking the time.

Cheers

[John Daniluk (JD)]

I just finished testing all of our DT12.   Most had broken wires in the plugs.   People do not take time to properly disconnect the plug and breaking the wires.  Our DT12 used standard color code.  The older cables suffer from corrosion from being in wet environments.  TAKE YOUR TIME when taking apart and assembling the connectors.   There are several good diagrams in internet for pin layout.

When testing,  I attach a breakout  box or cables to each end, then use a cable tester.  I have cut and rebuilt ends,  flux does help on old connectors.

note:  two pipe wrenches  helps when taking apart and assemble.  I know it is not the right tool but it works.

jd

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