Well, it was supposed to be a rewarding afternoon, if not fun. I got
sick and tired of all those silly little filters that have to be put
in line with every phone in the house in order to use ADSL. Also, a
guy from SBC told me that the more twisted-pair between the demarc and
the DSL modem, the better. I have been running all sorts of phone wire
around my attic to various rooms and I know a lot of it is not twisted
pair.
I recently changed ISPs and my old ISP "surprised" me with a $100
charge if I didn't return my old modem with filters. That sealed the
deal. I was determined to reduce the number of filters on my phone
system to ONE, once and for all!!
I sacrificed an extra filter I had, soldering wires to the "line in"
and "phone out" jack locations, then ran a rather nice 3-pair shielded
twisted-pair run directly from the demarc to where my DSL modem is.
Then, I wired my neat little modified filter between the demarc and
the rest of my interior wiring. "Ingenious!" I thought to myself,
expecting to go in and relax with a beer while surfing the web with
unprecedented reliability.
CRAP! My plan bit the dust when I went inside and found that my modem
was dropping sync all over the place. Just as bad as things were when
the phone company discovered a bridge tap on my line a few months ago.
After disconnecting my "miracle filter" at the demarc, it synced up
nicely. Curious, I connected a filter between the DSL modem and the
rest of the interior wiring at the modem location, and I continued to
get good sync. That's where I left things for now.
I am now very, very confused. I always thought one filter at the
demarc, with a dedicated direct line to the DSL modem, was the way to
go. Now I find it's not the case. At least the second best idea, a
dedicated line to the modem with a filter to the rest of the house,
seems to work. But why doesn't the filter work outside? Could it be
that my DSL modem sees the rest of the interior wiring, on the other
side of the filter, as a "bridge tap?" I always thought DSL modems
were "blind" to things on the other side of a filter.
Has anyone else tried this idea, and succeeded?
Just curious!
