WA3GIN in Alex. City, VA wa3gin at erols.com
Wed Dec 6 20:23:05 EST 2006

Pre-cable Internet there was a local ham that used to run 1kw into a Telrex
TB6EM about 50ft from the cable company's coax.  I could here him on my
cable TV and I knew who it was by his laugh. The cable company went to his
house and determined that several of the main trunk cable connectors were
not properly installed, had poor shield connections to the coax cable and
were allowing the strong 14MHz signal to reach the line repeaters which then
sent the RFI throughout the system.  After they replaced the trunk
connectors the problem was solved.

The good news is that it appears they understand that it is their problem to

Maybe they'll give your 6 months free cable for being a good sport ;-)


-----Original Message-----
From: rfi-bounces at contesting.com [mailto:rfi-bounces at contesting.com] On
Behalf Of Commander John
Sent: Wednesday, December 06, 2006 8:13 PM
To: rfi at contesting.com

Hi all
  Last evening about 9pm I noticed numerous  Time Warner cable TV service
trucks on my street, flashing lights and all.   Line men up on ladders at
the utility poles, all up and down the block.  After a while a knock on the
door.  The lineman wanted to know if I was a ham and if I was talking at
about 6pm or so.
  I said I was and they told me they were experiencing interference problems
and wanted to run some tests.  So I transmitted and It was confirmed.  My
being on the air shut down a entire node of roadrunner cable internet
service.  The lineman said some 200 were affected.  nice.
  This was on 3.967MC.  at 1500 watts.  They ran some more tests,
disconnecting my cable TV drop to isolate me from the system.  No noticeable
change. We found that at 30 watts they can tell when it is keyed on and off
but no one is kicked off the internet.  The tech said It was not back
feeding from my house but maybe the neighbors or the line.  On Saturday they
plan to return wanting my cooperation to allow them to drop houses one at a
time until they find the cause.  They claim they have been looking for this
intermittent problem for about a month. When they get to the complaining
home they find no problem.  I just don't talk that much.
  At my home there is no interference, cable TV is clear.   My computer
sitting next to the commander runs RTTY with the DSL internet on and stable.
I'm glad I can't afford road runner.  They begged me not to transmitt until
Saturday.  I find this all very interesting, and can hardly wait until the
problem is found.  Anyone have experience with these cable internet nodes ?
I don't have much experience with cable internet interference.  Mine was the
air conditioner fan turning on and off, while the garage door open itself
up.  All cleared up long ago.
  john w9zy
  I will post again when I learn more about this.
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