The Phone Repair Company
Impulse Noise
Brine, AT&T NC
Question:
We had a cut cable it was temporary replaced with a house cable no
Bond. The Power influence and the impulse now test out of standards.
The cell site fed by this cable is now taking ears. Could the
temporary cable have caused the problem?
Answer
I would look for open bonding first in about 98% of the Noise trouble
I work on that is the problem (Open Bonding could be in one place or
more).
Yes the cable can cause the Noise problem, the bond is now open from
the power neutral on the central office side to the next Power neutral
to the field (You have a large power section open that is not
canceling any induction on the cable pairs in that power section.)
Contact Jake if you have any
questions.
Burst Noise - (From Wikipedia, the free encyclopedia)
Burst noise is a type of electronic noise that occurs in
semiconductors. It is also called popcorn noise, impulse noise,
bi-stable noise, or random telegraph signal (RTS) noise.
It consists of sudden step-like transitions between two or more
discrete voltage or current levels, as high as several hundred
microvolts, at random and unpredictable times. Each shift in offset
voltage or current often lasts from several milliseconds to seconds,
and sounds like popcorn popping if hooked up to an audio speaker.[1]
Popcorn noise was first observed in early point contact diodes, then
re-discovered during the commercialization of one of the first
semiconductor op-amps; the 709.[2] No single source of popcorn noise
is theorized to explain all occurrences, however the most commonly
invoked cause is the random trapping and release of charge carriers at
thin film interfaces or at defect sites in bulk semiconductor crystal.
In cases where these charges have a significant impact on transistor
performance (such as under an MOS gate or in a bipolar base region),
the output signal can be substantial. These defects can be caused by
manufacturing processes, such as heavy ion implantation, or by
unintentional side-effects such as surface contamination.[3][4]
Individual op-amps can be screened for popcorn noise with peak
detector circuits, to minimize the amount of noise in a specific
application.
“There is no problem in any twisted copper cable that cannot
be located in a timely manner and a solution found for the repair of such
problem” - John “Jake “Jacobsen
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