[RFI] CATVI Problem
Marty Tippin <email@example.com>
Fri, 10 Jul 1998 16:21:41 -0500
Made some progress on the CATVI problem I've been having. Thought I'd pass
along an update...
The local cable company came out and checked the junction boxes in my yard
and the nearby ones - they found a pretty significant leak which was fixed
- they replaced the junction and the hardline connectors in my yard.
Haven't verified with the neighbors yet whether the TVI problem is lessened
or not, but I can't help but think it will be.
I was able to get through to the Director of Engineering at the cable
company (called the customer service reps, asked to speak to their
supervisor and once I explained what was happening, he put me through to
the engineering department.) I got lucky in that the Director of
Engineering and one of his subordinates who's responsible for my part of
town are both amateur radio operators, so they knew what I was dealing with
and were happy to help me out. Lesson learned: Be persistant, ask to
speak to someone in the Engineering section rather than the flunkies
answering the phones.
I ran into the service man this morning as he was checking things out, and
learned a couple of things about how to find leaks in the cable system (at
least in this area) - I hadn't read about this anywhere before so will pass
it along here:
* At 149.760 MHz is the voice information for cable channel 18. Sure
enough, I got to listen to some fine programming from Comedy Central until
he fixed the problem.
* The ARRL's RFI book says to listen at 145.25 for a leaking signal from
cable channel E - the service man informed me that the correct frequency is
at 145.26 MHz, and yes, there was quite a buzz emanating at that frequency.
After they finished, I hooked my HT up to the Ringo Ranger mounted up about
25 ft and could still pick up the signal on 149.76, just strong enough to
open the squelch. There is also a signal at 145.26 which opens the
squelch, but doesn't have any obvious sound with it. So there may still be
some leaks in the area. Will keep after the cable company on that one.
So, the plan now is to try some ferrite cores on the neighbor's coax and
electrical line - I'm also waiting for a super-duper RFI filter from
Industrial Communications Engineers (ICE) - I bought their top-of-the-line
AC filter / high-pass filter / common mode choke combo and will use it for
troubleshooting in the neighborhood.
So thanks again to all who have replied so far with suggestions on fixing
this CATVI problem - I don't have it beat quite yet, but I know how I'm
going to proceed, and that's makes it a lot easier to sleep at night.
Marty Tippin KI0LO | Tippin's Law #9: Stupid people outnumber the rest
firstname.lastname@example.org | of us by at least 5 to 1...
http://hbd.org/users/mtippin - Marty's Homebrew (Beer) Gadgets Page
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