If your wires are hard wired to the phone service then it's done wrong
or it's just old. The demarcation box should have a plug/jack so you
can disconnect easily from the POT (plain old telephone) line.
Installing a demarcation box would not be a bad idea once this is all
Didn't you say early on that you unpllugged the house from the phone
company? That plug/jack will do just fine to get rid of the voltage
in the hosue wiring.
My house only 28 years old, was built without a plug/jack outside, but
the phone company put one in for free (in the long run to save
themselves money, because they couldn't otherwise expect a customer to
be able to tell his house's problems from theirs.)
To get infinite resistance between the tip and ring, or whaever are
your two wires, you have to have everything with a bell or ringer
unplugged from the phone wiring in your house. And probbaly
everything that doesnt' have a ringer also. It's the wires that are
supposed to be separated from each other, not the appliances that plug
Now that I see you have done, properly I hope, the first set of tests,
I should tell you that I have suffered from hum for several years. I
did the Disconnect Everything tests and didn't find the problem. Then
because I was short of time, and I hadn't been able to use the phone
for a day, I ran some phone line from my computer, out the window, and
plugged into what I think RickH has been calling the demarcation, the
box outside the house. A bit later I plugged a phone in next to the
computer, and I ran a wire to my bedroom.
I ran that way for a year, until I had some time and was determined to
find the problem. I connedted things back the original way, and every
thing worked fine. For a year or two, then the hum was back.
This time I spent more time trying to solve the problem. My house has
insdie in the basement a little connection block where several sets of
phone wires are pushed into pinch connections, one set was original
with the house, one set I used to run phone line to the basement and
the master bedroom (where the original owner had sheet-rocked over the
phone jack) and the attic and the bathroom.
Anotehr set, of only two, I put in and it went to a jack 6 inches away
for use by my burglar alarm, and I think there was a 4th set but I
don't remember what it was for.
The wire is cut short with this type of device, when connections are
made by pros, but when I make the connections I live a few inches of
wire beyond the pinch connector.
Anyhow, if you have a connection place anything like this and you have
more than one set of wires, you can disconnect one set, and find out
if the hum is in that one or the others. In my case the hum was in my
set. Maybe mice? I only need two wires and I've run four, so I
should disconnect the red or the green and replace it with the yellow
or black. If that doesn't fix it I should replace the other. You
would use your colors. But I've been busy.
NO, you should get a very high reading, ie an open circuit.
But BEFORE you do that put your meter on AC volts and see if there's any
voltage betwen the two wires or from either wire to a nearby ground,
there shouldn't be.
I have a feeling that something has gotten wet somewhere and a little
bit of 120 volt line voltage is leaking onto your phone lines.
About four years ago I dropped our wired Verizon phone service because
every time it was raining there was a sizable "common mode" 60 Hz
voltage on both the ring and tip leads relative to ground. It didn't
bother an olde non-electronic phone, but the phones which used line
voltage to make them work would get an awful buzz. I measured the common
mode voltage at around 30 vac with my scope when it was raining and
almost nothing during dry weather.
Verizon tried switching me to different "pairs" a couple of times but
the problem remained. They were expecting to change over to their FIOS
fibre optic system in the next year or two and admitted to me that they
weren't going to put any effort into fixing their ancient leaky copper
No, zero would mean some sort of short.
A low value might mean a phone was connected and off the hook. It
would have to be an old phone with a magnetic bell to give a reading
close to zero.
BTW, my hum had nothing to do with wet weather. I'm thinking maybe I
pinched the wire when it ran through the attic. I may have put
plywood over it and then stepped on the plywood. (I don't think I did
that because I took precautions against that, but I'm running out of
Note that if this applies to you, make sure you call the alarm company
FIRST, and tell them, so they don't call for a police response thinking the
place is being attacked. Yeah, a faulty 'line seizure' block could add
static. Note that if it is a real fancy system, it may have an embedded cell
phone link as well.
The buzz is almost certainly electrical.
Flip off all circuit breakers. No buzz?
Turn 'em on one at a time until the buzz returns. Find the device on that
circuit that's the culprit.
It could be a bad florescent ballast, a bad CFL bulb, a motor (like on the
fridge), an electric clock, almost anything.
If, however, turning off the whole house does not remove the buzz, I'm
Maybe the power company has a leaky transformer, a defective reclosure,
If you get the power company involved, they will, I promise, respond much
faster than the telephone company. They've got vehicles chock-a-block full
of radio receivers that can pick up their "static."
Another trick you can try. Take a sledge hammer to the light poles, the ones
that have transformers hanging from them (looks like a garbage can). Give
the pole a mighty whack and see if the static goes away. You may need a
helper to tell you if the static goes away.
Still, the power outage you experienced, and the resulting surge when it
came back on, may have wounded something electrical at your house.
Peeopl have a lot more things than just phones connected to their
Try unplugging all of them, but one. The unplug that one and give the
line time to reset at the phone company office. Then plug in a
Consider your burglar alarm dialer, your modem, your caller-id box,
your cordless phone, your wired phone, your answering machine, and
maybe even specialty things most people don't have, like a central
redial box, an indicator light.
Go into each room to help yourself remember what is in there.
Did you drive any nails that could possibly have hit a wire. Just get
one phone working and then you can take your time getting the rest.
90 per half hour is a lot of money.
If you don't have a modern plug in demarc box, you might
still have a porcelin arrester with carbons in them. You might have taken
a overvoltage strike, and one of them is shorted out. They are usally in the
The newer ones are small with the round carbons inside.
You have one side shorted to ground. It could just be water somewhere.
Start at the Dmark and isolate the house from ther street side
(usually you just unplug "the house") Check it there with a phone.
If that is good it is in the house. If the street side is bad call
the telco. From there you just try to isolate each leg of the inside
runs until you find the bad part.
Suspect wires pinched under thresholds or other places where they can
I suggest you use a telephone connected to the Standard Network Interface
device (SNI/demarcation point) until you have called your phone company,
cancelled the current trouble report and subscribed to their inside wire
maintenance plan. You can then call-in a report with little concern about any
If your trouble occurred coincidental to a power outage, it is often something
left plugged-in to the phone line that became grounded. Surge strips with
phone outlets are often the culprit. Anything with an external power supply
(cordless phone base, modem w/power supply, etc) can cause such a ground on
the phone line.
If you have unplugged *EVERYTHING* in the house that is connected to the phone
line - including the RJ31 security system interface IF it has one (it SHOULD)
- and the buzz persists, the trouble is likely a GROUNDED conductor somewhere.
This is usually VERY difficult to find, even for a professional.
I have seen more than a few phone cords protruding from a window or door,
plugged directly into the SNI (bypassing the house wiring). This should give
you some "breathing" time to get signed-up for the maintenance plan or for a
lesser-expensive professional to repair the trouble.
Phone wire, unless it is approved for DIRECT BURIAL, should never TOUCH the
ground outside or under the house. If there is such wiring, it is likely the
culprit. Good luck.
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