Our phones went dead yesterday. Unfortunately, that's becoming
a common occurrence, and it has caused us to be very ticked off at
Comcast because we've been without service a lot.
Turns out maybe it's not their fault.
Oh, it was their fault originally. I know that because they
had techs out here three times fixing things. But this particular
outage isn't their problem because I can plug a phone right into
their modem jack and it works fine. It's distributing to the
rest of the hose that's the problem.
It's not my problem. This is a new house; it's all under
warranty, so I just called Customer Service (for the
community, not Comcast service) and the usual guys showed
up to take a look. I demonstrated the immediate symptoms and they shook
their heads and left, saying they'd be back later with tone injectors
and so on to trace it all down.
The Comcast modem sits in my closet. That may sound strange, but that
was the only place where a cable connection and a phone jack were
close together. It also keeps it out of sight and keeps it separate
from my other Comcast modem for Internet. This makes me happy
and also will let me switch to Verizon FIOS without confusion
if I want to.
So anyway: a line runs from the phone jack on the modem to
the wall jack, and that distributes phone service to every other
wall jack. Except right now it doesn't. I suppose I could
wait for the CS guys to come back, but I wanted to know myself,
which should be an easy enough thing to do consider the tools
I have in my trunk for testing network cables etc.
Well, yeah, except for "in my trunk". My wife has gone off to
medical appointments and will be gone all day. No car, no trunk,
No... not exactly no tools. I poked around in unpacked boxes
and came up with a voltmeter. The cable leads for it were a little harder
to find but a bit of rummaging turned those up. An AA battery
from the closet and a quick check - yes, the continuity test
works. OK, good so far. But the test leads were way too short to
reach from one phone jack to another. Hmmm..
More rummaging turned up a mostly empty spool of telephone
wire. Not much left on it, maybe 15 feet, but it just might be
enough. I couldn't find a wire stripper, but careful use of scissors
can strip the outer jacket and you can strip the inner stuff with your
fingernails. I found a screwdriver, took out the phone
jack in the closet and wired one end of my spool to it.
That brought me tantalizingly close to the other phone jack,
but not quite close enough. I could reach the wire and the jack
with the voltmeter cables, but I couldn't easily hold everything
in place and see the meter. I went back out to the garage
and started digging again.
Ahh, here's just the thing: Molly bolts. A nice screw head
to sock down the wires with, and a tight place to jam the voltmeter leads. Perfect. A bit
geekish, but it works.
I could now comfortably work at the other phone jack and quickly
found that while the green and red had continuity, yellow and black
were open. But wait: it's the green and red that have milliamp voltage
when the modem is plugged in, so they must be carrying the line.
And there's something else wrong: green and red are shorted: I can
read continuity right across them (with everything unplugged
everywhere). That doesn't seem right..I made sure my Molly's
weren't touching.. nope. This puppy is shorted in the wall
While ruminating over that, the CS guys showed up. I showed them
what I had and they looked confused. "It's not supposed to be
wired like that. Solid blue should be on the red."
Ok, that's fine with me - I didn't wire it. But it still shouldn't be
shorted. He agreed. We pulled all the wall plates (there are only
three, fortunately) and rewired as he wanted it. Still shorted, and still
no distribution of dial tone.
We then totally disconnected all wall plates, leaving bare wires
hanging. Still shorted.
I asked him why my yellow and black had no connectivity. "We
don't wire them in". Oh. Good to know, I guess.
We did observe some minor damage to the wire at one jack. There
was enough extra length to cut it back. Bingo, short gone. Momentary
jubilation as we hooked the plates back up. However, though the
short was gone, we still had no dial tone.
It's strange because I now have connectivity on each wire and no shorts.
I keep double checking myself because it makes no sense..
That's where it sits now. I can connect a phone directly to the Comcast
modem in the closet, but that's it. That's a bit inconvenient but at
least we do have a phone for emergencies. CS guys will be back
tomorrow or next week to hack at it more. I can live with it.
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