----- Original Message -----
From: <pringle50@home.com>
To: <wx5l@home.com>
Sent: Friday, December 21, 2001 4:25 PM
Subject: Cable Leakage
> Randy:
>
> Thanks for your E-Mail.
>
> Generally most cable systems have a specific frequency that they
> monitor which of necessity and by law, must be located within the RF
> spectrum the FCC calls the aeronautical band. The only way a cable
> company can use a frequency outside this range requires that their
> engineering staff correlate any readings in term of intensity to
what
> that signal would be at if the leak were in the aeronautical band.
> Most systems do not want to have to prove this correlation and
> accordingly locate to a frequency within the aeronautical band. Sad
> to say there is no standard frequency used so different companies
who
> manufacturer the measuuring equipment have favorites they prefer to
> sell cable companies and also various cable companies have their own
> desired frequencies that they prefer based upon the frequency
mapping
> of their respective systems.
>
> Different companies who manufacturer the leakage detection equipment
> use different modulation techniques and approaches to achieve the
> desired results so bottom line.....there is no standard.
>
> I would contact the Engineer of the respective cable entity in the
> area of concern to you and ask him specifically what frequency is
used
> in the respective system and whose equipment they use to monitor
> signal leakage. I'm sure he will be glad to provide you this
> information. If by some chance you run into a bonehead or someone
who
> is uncooperable, simply go to the office of the respective cable
> system and ask to see their FCC Public Inspection file and they can
> not deny you access to it. Within that file there SHALL BE a
complete
> listing of all frequencies transmitted through the respective cable
> system showing the precise carrier frequency, type of modulation
> employed on the carrier and specifically what the carriers function
is
> on the system and the specific transmission level at the highest
level
> employed in the system expressed in dBmV. If the system does not
have
> this information in their files or refuses to show it to you, then
> they are in violation of the FCC Rules relative to Cable Television
> and I would encourage you to contact the nearest office of the FCC
and
> talk with the Engineer-In-Charge.... I seriously doubt you would
have
> any problems...but just in case I felt I should give you an
> alternative just in case you run into an insensitive engineer or
> technical contact at the respective cable company.
>
> Hope this helps you and I'll be glad to answer any questions you may
> have as a result of what I have told you.
>
> I'm a retired electrical engineer and my last 15 years of
professional
> employment was with cable television. Been retired for 5 years this
> month and enjoying it!
>
> 73,
> J. Leon Pringle, Jr W 5 N A since 1974 and previous to that was
> W 5 Z R.
>
>
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