6.
Another reason for trouble on the line could be a grounded circuit. No, it is not attached to a
ground rod. This means that the insulation was worn off and one or both conductors may be touching
the ground. It could be in a puddle of water after a rain and the water seeped through the tape and got
into the splice. The traffic over the road could have worn the insulation off. Again you would be
looking for a ground.
7.
There is also the problem of picking up the telephone only to hear someone else on the line who
doesn't belong there. That is known as a cross. Somebody spliced the wrong wires together and your
private line between point A and B is now a private line from point A to point C. This could also
happen if several lines went through a tree together and the insulation has rubbed off. Not only could
you have a possible ground but a cross as well.
8.
Now that you know what problems may occur, you should be able to identify them by doing a
check on the line. We will discuss symptoms of trouble on the line.
a.
An open circuit disrupts or opens the line completely. There is no way for you to make
contact with anyone. It does not matter if one or both conductors are broken. There is no way for you to
make contact until you find the open. If you put a TA-312/PT on the line and turn the crank, it will be
very easy to turn with no drag. You will have the same result if the telephone is not connected to a line.
b.
A short circuit is just the opposite. If the TA-312/PT is on the line and you turn the
crank, it will turn hard and in an uneven motion. A low resistance short will disrupt communications
completely whereas a high resistance will cause weak transmissions and signaling. The telephone is the
best way to determine the problem.
c.
A grounded circuit will give different symptoms. If both conductors are grounded,
communications will be disrupted and you might think you have a short. Consider the splice in the
water. If you have a grounded circuit there could be noise or a hum on the line and you might think it is
an AC power hum.
d.
Crossed circuits are easy to identify. Strange people are on the line that should not be
there. If the line is a point-to-point line, the user of the telephone will know if there is a strange person n
the line. It is your job to locate the problem.
9.
Keep one thing in mind when troubleshooting. NEVER interrupt communications or any system
that is working to test it. You only work on troubleshooting when there is trouble on the line and you
are sent to find and fix it. Do not disconnect any line for any type of routine check. You work only on
those lines identified as having trouble.
10.
When trouble is identified on a circuit, the wireman will be the one to determine the fault, find it,
and fix it. You must remember that priority lines sometimes have to be rerouted while you are
determining the problem. Those high priority lines have that same high priority when trouble is
identified on the line. To aid in troubleshooting, sometimes you will be instructed to put in duplicate or
spare lines.
SS0440
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