[aprssig] Interference was 2m freqs in cable tv

Jim Lux jimlux at earthlink.net
Sun Mar 13 12:49:08 CST 2005

Max wrote:
I think the terms used in the community are  "unintentional" radiation and
"intentional" radiation.  We and all other other licensed radio stations are
licensed to transmit "intentional" signals.  "Unintentional' signals fall
within the category of interference and as such should be eliminated by the
responsible source.
73 Max KI6NJ

Steve wrote:
>Chris, My point was that the rules state that we are a licensed service
> and that any interference caused by an unlicensed service for the
> frequency must cease operation until the interference is resolved. It
> only happens when the interference is caused by an individual or a small
> company using illegal radios. All of these "incidental radiators" that
> also should be shut down, aren't.
> The FCC never has and never will follow their own regulations. My point
> is that we are low man on the totem. We just have gotten use to it when
> it comes to the cable systems.
> We don't "share" the spectrum with the cable company. They, along with
> BPL, are "incidental radiators". That is, frequencies that get out of
> "closed" systems that radiate in the open. So from that vantage point,
> they are apples and apples.
> Steve - WV0J

In fact, the FCC does go after cable companies radiating out of their
physical plant.  And imposes pretty stiff fines as well.  Check out the
enforcement branch's web site (http://www.fcc.gov/eb). [Field office
reports: http://www.fcc.gov/eb/FieldNotices/ ] In amongst all the stuff
about towers without IDs, obscenity complaints, places selling unapproved CB
radios, tower worker's safety suits catching on fire when they turn the
transmitter back on too early, etc., you'll find a few cases/month of cable
plants being cited for excessive radiation, or, for not having evidence that
they've done their required annual or quarterly scans of the physical plant.
Here's one for Comcast last week:

Granted, if you're Adelphia or Comcast or Time Warner, a $10K fine might be
viewed as a mere pimple, but I imagine that the local branch manager gets a
fair amount of heat from corporate about this.

However, don't necessarily expect instantaneous turn around.  It takes years
for the FCC enforcement process to grind through.  And, remember that the
enforcement process for most government agencies is very paper centric.
They move much faster if there are complaints that a licensee's "public
file" is not in order, or if there's a clear and present danger to public
safety.  If they're leaking in the 2m band, they're probably also leaking in
the aviation band, and you'll get MUCH faster response from the specter of
planes crashing than from inconvenienced hams. (note that the Comcast Notice
of Violation above was for 121.2625.. middle of Aviation band)

If the cable company hasn't been doing it's regular surveys, and didn't
catch the leak as a result, the FCC will stick them much harder than if it's
an "accidental" event from a failed component or some such.

Jim, W6RMK

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