Jim Redelfs wrote:

In article .com,
DerbyDad03 wrote:

- It still amazes me when I encounter a household with
NO line-powered corded) telephones.

While I understand your amazment, have you tempered that with the
extra cost for those of us who subscribe to the "all-in-one" services
of a cable company?

Yours is a legitimate issue. I suppose it is no different than subscribing to
the services of a single electric power utility - upon which virtually all of
us rely. Subscribing to TWO such feeds, even if a second were available,
would be cost prohibitive.

Coaxial cable-based telephone networks employ a vastly different and, in some
ways, improved technology whereby everything is delivered via one coaxial
cable. There is an "RT" (voice port) on the outside of most subscribers'
premises. It is there that the digital signal is converted to analog to
interface with your legacy telephone equipment. The current required to power
these individual terminals is delivered over the same coax from the
neighborhood's interface/node/whatever. It is this power (and the conversion
at the back of the house) that creates the dialtone heard when going off-hook
and the ringing current when a call is received. If you listen carefully at
this RT on the back of the house when receiving a call, you'll hear a small
relay clicking on-and-off, interrupting the ringing current.

I don't believe that I can have a line-powered phone unless I re-
subscribe with my telco and get a separate number. Since my modem is
dependent on power, I loose all of my phones, corded or not, during a
power outage.

This is not necessarily a given. If the CATV-based system has prompt standby
power, your dialtone could easily remain virtually uninterrupted or restore
much more promptly than the failed grid, which would empower "corded" phones
while cordless sets/systems would remain silent without their required grid
power.

I'm already paying for the cable company's phone service and a couple
of cell phones (which can be charged up/powered by my car or portable
jumpstart unit) so I'm not sure that paying for a line-powered backup
system makes economic sense.

Agreed. However, a POTS (Plain Old Telephone Service) phone, AKA a "corded"
phone, is a valuable tool to use at the interface for trouble shooting.
Regardless of who or what is providing your telephone service, a corded phone
might work when the lights go out. Keeping a CheapieChirpertm phone in a
drawer is cheap insurance.
--

JR

Traditional telephone service has historically been more reliable than
CATV service due to it's lack of active gear on the poles and remote
from the central office.

With traditional phone service each customer has their own wire pair all
the way back to the local telco central office switch so there isn't
anything but wire on the poles and the central offices have been built
to the old Bell Labs standards with substantial backup power.

CATV has always had active gear on the poles in the form of line
amplifiers and now fiber optic "nodes", so there has always been an
issue with needing to provide backup power at all those remote
locations.

The situation is rapidly changing now where growth of urban sprawl and
the need to provide data and video services to every customer has made
it necessary for the telcos to shift to the remote terminal model which
puts active gear in the field just like with the CATV system and
subjects them to the same remote backup power needs.

Basically the old notion of the telephones always working is going out
the window just as rapidly as the old notion of the cable never working.
In many areas where the telcos RT transition is in place, which also
correspond to areas where the cable operators are the most up to date,
both services are of comparable, reasonably high reliability.