On Sat, 27 Feb 2010, JOHN MACKEY wrote: > Using balanced audio in a broadcast environment, I have on rare > occasions experienced issues with cross-talk between long runs of > un-shielded balanced audio lines. (inductive pickup??) I always > wondered if the wires were truly balanced when that happened.
That's probably NEXT or FEXT, which is near-end cross-talk and far-end. Bell documented this stuff somewhere; I've read the book. There's a reason why they don't run the T1 lines with the voice lines or why they don't stuff the entire binder full of T1s. Of course, that same book explained how to use the cable pairs as resistors to heat up the cable, which has been done a few times in NYC, resulting in dead pairs in the cable due to too much power/heating on a given pair. -- Kris Kirby, KE4AHR Disinformation Analyst
