Ring voltage measurment question [telecom]

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I have a traditional rural land line with two 2500 sets [1] attached.
Recently I've been getting intermittent weak ringing: sometimes a
ring, sometimes a weak chatter (no gong), sometimes nothing audible.
Moving the clapper spring to the low-voltage position seems to have
fixed it for now.

But I'd like to figure what's going on and call the telco service guys
if the voltage is low or there's a potential for further
deterioration. (Voice and (tone) dialing work as expected.)

Can I get a meaningful ring voltage reading using an inexpensive
analog multimeter on the "AC Volts" setting?  Or do I need a different
(or better) meter for (AIUI) 22 hz measurements?

And do I measure the voltage across the two wires while both phones
are attached to the line?  At the demarc?  Or should I try to do it
with both phones disconnected?


[1] Yes, real ones with two gongs. I think they're both Nortel.  Not
    recent Chinese knock-offs.

--
Mike Spencer                  Nova Scotia, Canada

mspenbellscer@tallwhistlesships.ca
(remove bells and whistles)

Re: Ring voltage measurment question [telecom]
wrote:
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A friend of mine, in a rural location, had ringing trouble.  He called
his local telephone company and they added something to the line
pole.  The problem was resolved.

One test you might make is plugging in a phone at the demarc box,
isolating out the phones in your house, then calling the phone.  If
that phone rings ok, it would suggest there is a problem in your house
wiring, perhaps a short or leak.  If that phone fails to ring, then it
probably is a telco problem.

Two conventional telephone sets is not a large ringing load and they
should work fine.  Perhaps you should report it to your phone company
and let them try to fix it, before you go to the trouble of
measurements, etc.  Good luck.

Re: Ring voltage measurment question [telecom]
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[...]

My guess is a corodded connection somewhere between your phone and the
CO.

Measure ring voltage (an analog multimeter would be best) at the NIJ and
at your phones.  A significant difference would place the bad connection
on your territory.  Little or no difference puts it in the telco's lap.

Also see if a phone rings better at the NIJ than its normal place.  This
would also indicate the problem is yours.

A partial short would have a similar effect and test.

--
Rich Greenberg  Sarasota, FL, USA richgr atsign panix.com  + 1 941 378 2097
Eastern time.  N6LRT  I speak for myself & my dogs only.    VM'er since CP-67
Canines: Val,Red,Shasta,Zero,Casey & Cinnar (At the bridge)   Owner:Chinook-L
Canines: Red & Max (Siberians)     Retired at the beach  Asst Owner:Sibernet-L

Re: Ring voltage measurment question [telecom]
On 05 Jun 2012 01:56:06 -0300, Mike Spencer wrote:

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Help me understand: this "weak ringing" or "chatter" is taking place as an
incoming call is trying to notify you it's coming in? -- if so, it gives
the appearance of either a too-low ringing voltage, or some resistive
degradation in your wiring. Or is it the sort of bell-activity that
reflects some random high-amplitude noise, or perhaps stutter dial-tone, on
your line -- if that, I've encountered it, and it lasted until some years
later, when a nest of squirrels on the outside overhead pole wires resulted
in so much squirrel-tooth and squirrel-poop damage to the conductors that a
truck-roll was needed to string up new wire. New wire => no more chatter.

Cheers, and best of luck, -- tlvp
--
Avant de repondre, jeter la poubelle, SVP.

Re: Ring voltage measurment question [telecom]

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Yes. Answering the slightly twittering phone reveals an incoming call.

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Yes, since setting the clapper to the low voltage position fixed it.
For now.  But will it get worse?  Hence the effort to determine the
origin of the problem.

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Wire is open to view for half a mile at least.  No squirrels, bird
nests or the like in evidence.

Replies from richgr@panix.com (Rich Greenberg) and HAncock4

I'll follow up on your suggestions, some of which I hadn't thought
of.

In particular, richgr@panix.com (Rich Greenberg) wrote:

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Oh, good.

Thanks, all,

--
Mike Spencer                  Nova Scotia, Canada

Re: Ring voltage measurment question [telecom]
richgr@panix.com (Rich Greenberg) wrote:

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Okay. That gives me a little confidence.

Analog multimeter says that during ringing there'a 18 volts across the
terminals of the (outside) NIJ and across the terminals of the
(indoor) block into which the phone is plugged. Sheesh!

Ring is the only problem; none with calling out or sound quality.

Next stop: telco service folks, but armed with a little knowledge.

Thank you.

--
Mike Spencer                  Nova Scotia, Canada

Re: Ring voltage measurment question [telecom]
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Make a couple of additional tests, first.

  0) first, disconnect -all- phone equipment -- sets, answering machines, etc.

  1a) measure the 'not ringing' voltage at both the NIJ and the internal block.
      (use "DC volts" setting, try the probes in both combinations)
  1b) also , measure the 'not ringing' current flow (use a 'DC 100 milliamp'
      setting) through the two wires, both at the NIJ and at the internal
      block.

  2)  measure the 'ringing' voltage at both the NIJ and the internal block.
      (use "AC volts" setting, try the probes in both combinations)

Re: Ring voltage measurment question [telecom]
[Quoting at possibly excessive length...]


bonomi@host122.r-bonomi.com (Robert Bonomi) writes:

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The telco guy came before I did all that.

He measured the ringing & non-ringing voltage as DC!  He claimed
twenty-mumble years on the job, had never been asked to deal with ring
voltage, insisted that the only meaningful measurement was DC
voltage. 52 VDC at the demarc (NIJ? Outdoor thingy between my wires
and theirs) and at the cabinet 5 miles away. Slightly higher when
ringing.  Dismissed my measurement of 18 VAC when ringing as not
meaningful. He went away content that there was no problem leaving me
confused. Happens that phones rang as they should when he was here.

That's all contrary to what y'all have told me here (measure AC ring
voltage at, should be 40V to 90V).  Did I draw a complete dummy tech?
It's not as if a 20+ year guy has never seen a 2500 set or a phone
that has a "real" ringer. There are folks here with old rotary-dial
sets.

Oh, well, I'll follow your directions, Robert, and file results for
future reference.  Grumble...mutter...

Tnx,
--
Mike Spencer                  Nova Scotia, Canada

Re: Ring voltage measurment question [telecom]
On 6/10/2012 1:06 AM, Mike Spencer wrote:

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Mike,

I suggest you follow these steps:

1. Borrow a "Genuine Bell Canada" phone, and plug it in at the demarc.
   Don't use your own phone: you need a "Known Good" instrument for
   this test. If the problem persists, it's their trouble. If not,
   it's yours.

   ("Genuine Bell" is important: phones from other manufacturers often
   have non-standard ringers that the techs won't trust. When you can
   point to a label that shows it is/was their instrument, they'll be
   less likely to blame the phone.)

2. If the test shows a problem in the telco network, I suggest you

   A. Send a letter to the Nova Scotia PSC, and ask any neighbors who
      have had the same problem to co-sign it:

      Public Service Commission
      1800 Argyle Street, 5th Floor
      PO Box 943
      Halifax, Nova Scotia
      B3J 2V9

   B. Contact your MP, and complain at length about poor service. It's
      important to use longhand when you write, because politicians
      place great weight on hand-written letters.

HTH.

Bill

--
Bill Horne
(Remove QRM from my address to write to me directly)

Re: Ring voltage measurment question [telecom]
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[ sneck ]
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*Generally* if there's something wrong with the -wiring- between you and
the C.O. it will affect both battery and ring.  There are exceptions,
but they are rare.  If the voltage is good, *and* the 'shorted' current
at the DEMARC is rational, that pretty much clears the telco wiring.

This leaves the possibility of an 'intermittent' wiring problem, but
the fact that you have a 'usable' voice connection when you take a
phone off-hook after a 'bad' ring, tends to eliminate the possibility
of something in the telco wiring.  This leaves only a couple of
possibilities:

  1) *inside* the phone that you picked up. specifically in the ringer
     circuitry of that phone.  If you've got multiple phones, and they
     all have 'weak ring' when there's a problem, and you can pick up
     any phone and have good voice volume, that eliminates =this=
     possibility.

  2) _at_ the C.O, or 'remote'.  Specifically, a bad 'ring generator'.
     When a good ring generator is switched on to your line, the phone
     rings properly.  when the C.O. selects the _bad_ one, you get the
     "low-voltage" ring issue.

Also, you might try measuring the AC voltage during a good ring _and_
when a 'weak' one occurs.  This'll give you some additional ammunition
if you have to call the telco in again.

Re: Ring voltage measurment question [telecom]
bonomi@host122.r-bonomi.com (Robert Bonomi) writes:

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Two phones. When the problem occurs, both ring feebly or not at all.
Both have good voice volume (and no static or hum) when picked
up. Same after one of the phones has been swapped for another.

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The problem has not recurred since the telco tech was here. Nothing
was dis- and re-connected here.  I suppose it's possible -- wild
surmise -- that when he "checked" the voltage at the cabinet out on
the highway [1] he tweaked or bumped something that altered the ring
voltage or generation.

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Good idea. And I can do that beacuse, for now, ringing is good even
with the 2500 clapper spring set in default position.


Tnx.



[1] Is there a name for that cabinet?  The central office is ca. 13
    miles away, the cabinet only 4 as the wire runs.

--
Mike Spencer                  Nova Scotia, Canada

Re: Ring voltage measurment question [telecom]
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Frequently referred to, generally, as a 'vault', especially if underground.
Above-ground units may be called a 'pedestal' (if small) or a 'hut' (if big
enough to walk into).

Beyond that, "it depends".  <grin>

It -may- be nothing more than a splice point, where multiple small feeder
cable runs that each feed a group of residences are connected to a single
larger trunk cable that runs back towards the C.O.  Depending on geography
and the density of subscribers, there may be more than one level of this
'concentration' into bigger cables.

*OR* it may have active electronics in it.  Anything from a full 'remote'
extension of the C.O. switch, down to just a 'channel bank' equivalent
which breaks out a multiplexed, (usually) fiber,  circuit from the C.O.
into the individual copper circuits to the customer premises.  There are
different names for this kind of an installation, depending on what kind
of functionality (and the degree of autonomy from the C.O. switch) that
the on-site electronics provide.

'vault'/'pedestal'/'hut' describes the physical enclosure, without any
assumptions, implicit or otherwise, about what is 'inside' the enclosure.

Re: Ring voltage measurment question [telecom]
bonomi@host122.r-bonomi.com (Robert Bonomi) writes:

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[further details snipped]

Medium sized, two-door cabinet, not walk-in.


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Yes, but also like the one at:

   http://en.wikipedia.org/wiki/Remote_concentrator

Rural area, guessing a few hundred scattered dwellings, no industry or
commerce nearby. A friend who lives close -- 1/2 mi. -- to a similar
cabinet (but far from the CO) can have ADSL because of that
proximity. That may identify what lives in the cabinet.

Would the telco device that actually generated my ring voltage be
located in that DLC/RLC/box?

I know, I know, "it depends". :-)  I'll have to go take a closer look
at it.  If there's a nice little tag that identifies it, it isn't
readable when passing at the usual 100' at highway speed.


Tnx,
--
Mike Spencer                  Nova Scotia, Canada

Re: Ring voltage measurment question [telecom]
bonomi@host122.r-bonomi.com (Robert Bonomi) writes:

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At one point, 8 or so years ago, a management guy (pinch-hitting for
striking techs) claimed to have replaced a "circuit board" in the
cabinet in question. Small factoidal evidence for "probable".

I still find it hard to believe that a Bell Aliant tech told me stuff
that, according to y'all here on c.d.t. and others elsewhere, was
flatly wrong. Working on it.

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I've been both bitten and blessed that LoPS.

Tnx,
--
Mike Spencer                  Nova Scotia, Canada

Re: Ring voltage measurment question [telecom]

[Moderator snip]

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Probably Digital loop carrier.

http://en.wikipedia.org/wiki/Digital_loop_carrier

Does the box you mention look like the photo in Wikipedia?

Neal McLain

Re: Ring voltage measurment question [telecom]

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The clue is: does it get power? Any DLC will need power,
and backup battery within.

If no electric meter, it's a 'cross-connect cabinet' or 'xconn'
or 'XC'. Local usage varies; the term IDF for 'intermediate
distribution facility' may be used in other places.

But at 68 kilofeet, I'd think DLC.


--
A host is a host from coast to coast.................wb8foz@nrk.com
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

Re: Ring voltage measurment question [telecom]

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Wow, that should ideally be 90 volts.

Re: Ring voltage measurment question [telecom]
RonTheGuy@null.invalid (Ron) wrote in news:1klb6ws.oopg46dxj39kN%
RonTheGuy@null.invalid:

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Minimum ring voltage at the NI: 55V RMS @ 20/30 Hz (Depending on ILEC).

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