>From KPRC Channel 2 (Houston NBC Affiliate) web coverage
(http://story.news.yahoo.com/news?tmpl=story&cid=320&e=3&u=/ibsys/20040225/l
o_kprc/2023463).
Interesting to see this topic in the mainstream media.
----
Leaky Cable Signals Interferes With Communication Airwaves
Wed Feb 25, 6:41 PM ET
At any given time more than 36,000 cable users have a signal that is
leaking.
The leaks are not harmful, but if the so-called leaks are left unchecked
they do have the potential to interfere with some of our most critical forms
of communications.
"I thought it was a scam," News2Houston meteorologist Frank Billingsley
said.
Like other cable users from Galveston to Conroe and Katy to Baytown,
Billingsley was more than a little skeptical when he got home and found a
notice hanging on his front door concerning a problem with his cable.
"I thought it was somebody trying to figure a way to get into the house by
saying, 'Oh, we need to come fix your cable,'" Billingsley said.
The notice told Billingsley and other cable customers that their system
needed to be fixed immediately because it was leaking its signal -- a signal
that can interfere with aeronautical and government communications.
"I just thought the cable, being a closed system, how in the world does it
transmit a signal that could interfere with an airplane 5 miles up?"
Billingsley asked
TV stations, police and fire department radios, and airplanes are all
considered primary users of the airwaves. Cable is considered a secondary
user.
Because cable uses many of the same frequencies as the others, its signal
has to be contained. If that cable signal leaks, it can interfere with the
other forms of communication being transmitted.
A leak can cause something as simple as bad reception on your TV or as
complex as interfering with communications between a pilot and an air
traffic controller.
The Federal Communications Commission (news
<http://us.rd.yahoo.com/DailyNews/manual/*http://search.news.yahoo.com/searc
h/news?p=%22Federal%20Communications%20Commission%22&c=&n=20&yn=c&c=news&cs=
nw> - web sites
<http://us.rd.yahoo.com/DailyNews/manual/*http://dir.yahoo.com/Government/U_
S__Government/Agencies/Independent/Federal_Communications_Commission__FCC_/>
) requires all cable companies to fix a signal leak when it reaches 50
microvolts.
Time Warner, which services the Houston area, will fix a leak when it
reaches 20 microvolts.
"If you have any break or crack, or any kind of loose connection, (a leak
detector) will pick it up," a Time Warner repairman said.
Cable companies first pinpoint which houses have leaks by constantly driving
neighborhoods measuring microvoltage leaks. After a leak is detected, an
engineer has to pinpoint the source.
Every line is checked and when the detector goes silent, the source of the
leak is found.
In Billingsley's case, the leak was something as simple as loose
connections.
But the most common reason for signal leaks are the do-it-yourselfers.
"The problem happens when a customer might add a new TV set. They do the
wiring themselves and they're using wiring that is subpar and not up to
cable standards," Time Warner Cable spokesman Ray Purser said.
Satellite users have no need to worry. The reason satellite dishes do not
cause this problem is because that signal uses a different frequency so it
does not conflict with the so-called primary users of the airwaves.
Time Warner told News2Houston customers have seven days to schedule a repair
call or their cable will be shut off
----
Larry Burke WI5A
Friendswood, TX
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