Thanks, Dave, for your detailed reply -- lots of good tips. You're right,
of course. It really isn't my responsibility if the cable company is
putting out equipment that can "listen in" on my HF transmissions. I'm sure
my equipment is clean. Actually, before I go out and buy a collection of
ferrites and suppressors, I think I'll just encourage my friend to complain
to the cable company. They should be the ones fixing this.

And, if you're _exceptionally_ lucky, the cable company might actually
send out a tech who has the necessary amount of Clue in his van to
diagnose and fix it correctly.

I'll keep my fingers crossed for you.

Or, am I being naive here. Could they make more trouble for me than it's
worth even if I am "innocent."

Their equipment is almost certainly bearing a Part 15 certification,
which means that they don't have a leg to stand on... it "may not
interfere" with licensed radio services and "must accept" any
interference from same.

One additional thing I'd suggest: have your neighbor disconnect all
of his "inside" wiring from the cable/phone adapter, and plug a single
phone directly into the adapter. Ideally, use an old-style
non-electronic desk phone. Then, have him make a call, and try keying
down CW. If he still hears interference on the line, then the adapter
is certainly responsible.

In this case, he can use the magic words with the cable company:
"Interference is present at the demarc, with all inside wiring
disconnected." Legally, that means "It's your problem, come fix it!"

If the problem is present only when the house wiring is connected, the
issue may be a bit more sticky. It's still not _your_ fault (as the
radio operator), but there may be a question as to whether the fault
lies in the cable-company equipment (which is their responsibility) or
in the house wiring or equipment. Unfortunately, I suspect that the
basic fault lies in the cable equipment, but may only show up when the
inside wiring is connected because the inside wiring is acting as an
antenna. If your neighbor isn't paying for "inside wiring" service -
if he "owns" the inside wiring - then the cable company may try to
argue (lamely) that paying for the repair is his problem.

On the other hand, the cable company may know about the problem in
their equipment (from other cases) and may be willing to fix or
mitigate it without complaint. No way to know for sure unless you
(and he) make the call and try.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
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