+ 0 Votes Used the Diagnostic Tool mpersic 3 years ago Yes, I have the diagnostic tool (using one at each end). The tool does show the signal to noise ratio and link state. However, it doesn't show "why" the link is down. With the oscope I was hoping to identify a frequency or noise burst that was causing the link loss. If I could see the noise then I have a better chance at determining the source. Interesting that the POTS telephone (which shares the same 50 pair commline) is complete static a lot of the time when the link is sometimes up and always when the link is down.Replacing the commline is not an option (due to resources) and the commline was installed new. The conductors all check out at about 150 Ohms from end to end.