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[RFI] Cable TV Signal Leakage (Long but hopefully helpful)

To: <rfi@contesting.com>
Subject: [RFI] Cable TV Signal Leakage (Long but hopefully helpful)
From: pringle50@home.com (pringle50@home.com)
Date: Mon, 10 Dec 2001 08:56:29 -0600
This is a multi-part message in MIME format.

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BlankThere have been numerous posts on this reflector concerning signal =
leakage from a Cable TV System some of which are not entirely accurate =
and some contain assumptions.  Perhaps this is a good time to clarify =
the situation with regard to the FCC Rules.

Cable TV Systems in most cases use frequencies to transmit their =
programming through their outside cable plant that are primarily =
assigned to other entities, some of which are primarily assigned to =
amateur radio.  The Cable Companies are allowed to use these frequencies =
IF and ONLY IF they comply with the FCC Rules relative to signal =
leakage.  Briefly a cable TV systems is suppose to be a closed loop =
system if properly engineered, installed and maintained and signals =
should be able to be distributed to customers so that they can enjoy the =
entertainment of cable TV and other users of the spectrum that cable is =
using on a secondary basis can be utilized by the primary licensed =
service.

The FCC rules relative to signal leakage are very, very clear and have =
no room for ambiguity or misunderstanding by competent technical =
persons.  A small amount of leakage is allowed but basically 20 =
microvolts/meter at a distance of 30 feet from the leakage point is the =
dividing line.  Leakage in excess of this amount is a violation of the =
FCC Rules and require that the offending cable system correct in a very =
timely manner.  Failure of the Cable System to correct could very well =
lead to a citation by the FCC ordering that the leakage be fixed or that =
the frequencies used that are within the spectrum considered =
aeronautical could be shutoff until the Cable Operator corrects the =
signal leakage problem.

The FCC requires that once per year and on an annual basis, each cable =
system utilizing frequencies in the aeronautical spectrum must certify =
to the FCC that the respective system complies with the FCC Rules =
relative to signal leakage.  The FCC allows the cable system to certify =
by (1)a flyover were an aircraft equipped with suitable calibrated =
receiving equipment flyover the entire system measuring the field =
intensity of the leakage or (2) a rideout of the entire cable plant =
including the headend utilizing calibrated receiving equipment.  The =
system simply will not pass if there are any substantial number of leaks =
which one would anticipate on a system not maintained properly. =20

The cable system can develop a leak at anytime at anyplace and =
accordingly must be repaired in a reasonable time (few days) and CAN NOT =
wait until the next annual certification to perform the leak correction. =
 In any good Cable System the service technicians have leakage detection =
equipment in the service trucks and as the technicians go about the =
performance of their installation and maintenance duties on a daily =
basis, log the leaks they detect on the signal leakage equipment as well =
as their mileage run that day and report them to the responsible =
technical person.  These logs must be available for inspection at =
anytime by the FCC.  Using this approach the FCC expects that the =
mileage tested in this fashion must equal or exceed 100% of the total =
outside plant cable mileage EVERY QUARTER of the year.  This is in =
addition to the annual certification which is a stand alone test.

Cable Systems CAN NOT hide behind an annual certification test on Signal =
Leakage Compliance for not repairing a signal leak in excess of the FCC =
allowance of 20 microvolts/meter at a distance of 30 feet.

Be persistent in dealing with the technical staff of the local cable =
operator until you get results.  If you don't after giving them a =
reasonable time to solve your problem, contact the Engineer-In-Charge of =
the nearest FCC Office for his assistance. =20

Rest assured that Cable Systems would rather hear from you than have a =
pilot flying overhead on a large signal leak in a system which would =
break the squelch of his aeronautical radio/navigational equipment and =
report it directly to the FAA and FCC.  That gets the cable operator a =
visit EVERYTIME from an FCC representative and into potential trouble =
and perhaps fines. =20

73,
J. Leon Pringle, Jr    W 5 N A=20
E-Mail:   w5na@mdxa.org
             w5na@megagate.com
             pringle50@home.com


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<BODY bgColor=3D#ffffff background=3D"Blank Bkgrd.gif">
<DIV>There have been numerous posts on this reflector concerning signal =
leakage=20
from a Cable TV System some of which are not entirely accurate and some =
contain=20
assumptions.&nbsp; Perhaps this is a good time to clarify the situation =
with=20
regard to the FCC Rules.</DIV>
<DIV>&nbsp;</DIV>
<DIV>Cable TV Systems in most cases use frequencies to transmit their=20
programming through their outside cable plant that are primarily =
assigned to=20
other entities, some of which are primarily assigned to amateur =
radio.&nbsp; The=20
Cable Companies are allowed to use these frequencies IF and ONLY IF they =
comply=20
with the FCC Rules relative to signal leakage.&nbsp; Briefly a cable TV =
systems=20
is suppose to be a closed loop system if properly engineered, installed =
and=20
maintained and signals should be able to be distributed to customers so =
that=20
they can enjoy the entertainment of cable TV and other users of the =
spectrum=20
that cable is using on a secondary basis can be utilized by the primary =
licensed=20
service.</DIV>
<DIV>&nbsp;</DIV>
<DIV>The FCC rules relative to signal leakage are very, very clear and =
have no=20
room for ambiguity or misunderstanding by competent technical =
persons.&nbsp; A=20
small amount of leakage is allowed but basically 20 microvolts/meter at =
a=20
distance of 30 feet from the leakage point is the dividing line.&nbsp; =
Leakage=20
in excess of this amount is a violation of the FCC Rules and require =
that the=20
offending cable system correct in a very timely manner.&nbsp; Failure of =
the=20
Cable System to correct could very well lead to a citation by the FCC =
ordering=20
that the leakage be fixed or that the frequencies used that are within =
the=20
spectrum considered aeronautical could be shutoff until the Cable =
Operator=20
corrects the signal leakage problem.</DIV>
<DIV>&nbsp;</DIV>
<DIV>The FCC requires that once per year and on an annual basis, each =
cable=20
system utilizing frequencies in the aeronautical spectrum must certify =
to the=20
FCC that the respective system complies with the FCC Rules relative to =
signal=20
leakage.&nbsp; The FCC allows the cable system to certify by (1)a =
flyover were=20
an aircraft equipped with suitable calibrated receiving equipment =
flyover the=20
entire system measuring the field intensity of the leakage or (2) a =
rideout of=20
the entire cable plant including the headend utilizing calibrated =
receiving=20
equipment.&nbsp; The system simply will not pass if there are any =
substantial=20
number of leaks which one would anticipate on a system not maintained=20
properly.&nbsp; </DIV>
<DIV>&nbsp;</DIV>
<DIV>The cable system can develop a leak at anytime at anyplace and =
accordingly=20
must be repaired in a reasonable time (few days) and CAN NOT wait until =
the next=20
annual certification to perform the leak correction.&nbsp; In any good =
Cable=20
System the service technicians have leakage detection equipment in the =
service=20
trucks and as the technicians go about the performance of their =
installation and=20
maintenance duties on a daily basis, log the leaks they detect on the =
signal=20
leakage equipment as well as their mileage run that day and report them =
to the=20
responsible technical person.&nbsp; These logs must be available for =
inspection=20
at anytime by the FCC.&nbsp; Using this approach the FCC expects that =
the=20
mileage tested in this fashion must equal or exceed 100% of the total =
outside=20
plant cable mileage EVERY QUARTER of the year.&nbsp; This is in addition =
to the=20
annual certification which is a stand alone test.</DIV>
<DIV>&nbsp;</DIV>
<DIV>Cable Systems CAN NOT hide behind an annual certification test on =
Signal=20
Leakage Compliance for not repairing a signal leak in excess of the FCC=20
allowance of 20 microvolts/meter at a distance of 30 feet.</DIV>
<DIV>&nbsp;</DIV>
<DIV>Be persistent in dealing with the technical staff of the local =
cable=20
operator until you get results.&nbsp; If you don't after giving them a=20
reasonable time to solve your problem, contact the Engineer-In-Charge of =
the=20
nearest FCC Office for his assistance.&nbsp; </DIV>
<DIV>&nbsp;</DIV>
<DIV>Rest assured that Cable Systems would rather hear from you than =
have a=20
pilot flying overhead on a large signal leak in a system which would =
break the=20
squelch of his aeronautical radio/navigational equipment and report it =
directly=20
to the FAA and FCC.&nbsp; That gets the cable operator a visit EVERYTIME =
from an=20
FCC representative and into potential trouble and perhaps fines.&nbsp; =
</DIV>
<DIV>&nbsp;</DIV>
<DIV>73,</DIV>
<DIV>J. Leon Pringle, Jr&nbsp;&nbsp;&nbsp; W 5 N A </DIV>
<DIV>E-Mail:&nbsp;&nbsp; <A =
href=3D"mailto:w5na@mdxa.org";>w5na@mdxa.org</A></DIV>
<DIV>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&n=
bsp; <A=20
href=3D"mailto:w5na@megagate.com";>w5na@megagate.com</A></DIV>
<DIV>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&n=
bsp; <A=20
href=3D"mailto:pringle50@home.com";>pringle50@home.com</A></DIV>
<DIV>&nbsp;</DIV></BODY></HTML>

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