How is cross connection of telephone caused??

Question

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Answer 1

Several ways. Some of the more common are watter getting into a cable or wireing errors at the telco switch. That can be due to relay problems or cable chaffing.

Answer 2

I think you have your terminology wrong... "cross connection" refers to "jumper" wires that connect inside the telephone terminal, or at a connection block (66 or 110 block)

I think you are referring to cross talk, which is when multiple lines are defective, and can talk back and fourth with each other, unlike an induction trouble which many customers confuse as a crossed line, or cross talk, where the conversation of one (or more) lines is heard in the back ground, but can not talk back and fourth with each other.

CROSS TALK (can hear and talk with other line):

1- human error, or incomplete work outside. When a line is installed in a terminal that does not have any more spare pairs to the central office, a line station transfer is done (LST) where a working line from another terminal is moved to make a spare in the "home" terminal during the time this work is being performed both lines will be connected together for a brief time

2- failure to break cut-thru on a new installation. when a line is newly installed, the cable/pair may have feed to a diffrent location from a diffrent terminal, sometimes out of laziness, or lack of experience the old terminal is not checked to ensure the wire has been removed.

3- error in telephone cable splicing, where the count is off, and one line comes connected to another somehow.

4- rain or moisture on the telephone wiring outside, either in a flooded manhole, or improperly sealed splice case or terminal

5- old paper sheathed wiring

6- metallic troubles: ground, cross-battery

INDUCTION (hear others on line in background, can not talk back and fourth)

1- unbalanced pair, a telephone wire runs on a pair of wires (2-wires) if one wire is longer then the other it can act as an antenna and pick up other conversations, and even radio reception in some cases.

2- a split pair, between terminals, manholes, and the central office each pair of wires is a twisted pair, if there are no spare pairs within a terminal, and only defects a tech will usually split the pair, using one good side of 2 diffrent pairs of wires, which are no longer a single twisted pair, but 2 separate wires running parallel with the other pairs in the phone cable,  this can cause the wire to act as an antenna and pick up conversations, and radio reception...

3- a ground on the line, having one side of the pair grounded will cause an audible hum on the line and may also cause you to hear others on the line sometimes being able to talk back and fourth, but normally just hearing them in the back ground

4- and old, out-dated cordless phone can sometimes pick up other radio transmissions (cordless phones) within its range. this is a rare occurance, and does not happen with modern DECT cordless telephones