maximum number of devices on POTS line? (a tale of dialup woe)

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Apologies in advance if this group is supposed to be for working pros only.

Subject says it all, almost. Finally bought a house, and hooked up all the
various computers, real Ma Bell phones, satt receiver, answering machine,
etc. Ran into problems- some of the 2500s couldn't break dial tone, poor
connections on the modems, etc. Only reliable way to make things work is
unplug devices down to 4 or less. Testing at demarc with laptop, I only get
40k, since I am so far from telco. Inside, by itself, laptop gets 40k on any
jack if it is the sole device connected. I do have most of the ringers
disconnected to keep the REN total as low as possible. Or does REN really
apply to the device itself, not just the ringing function?

Note that I did have all the same junk hooked up in my previous apartment,
and it all worked, albeit slowly, behind multiple pedestals and punchdown
blocks.

Inside wiring at the new place is 4-color solid untwisted. I have snugged or
redone all the splices in basement, and snugged all the wall jacks. They
used the original inside 4-post wiring block as a junction block front-fed
from new demarc, till posts got full, then switched to floating-in-air
gunk-filled Scotchlok crimp connectors for the additional branches. It is a
mess.

Yes, I  would prefer a home-run wired 110 block or patch panel with cat 5e,
but before I go the expense and bother, is it likely to gain me anything,
since the connection is only so-so at the demarc? Ma Bell (SBC) already ran
onsite diagnostics for me, and claims the drop is fine. (Not to mention, no
place around here sells real connection hardware, just the made-in-china
plastic crap, or faux modular patch panels for 'system' wiring. I'd have to
hire the work out, or spend a couple hundred online ordering the the real
parts and cable and punchdown tool for a one-time requirement.)

I know - I should just get broadband, but DSL isn't available this far out,
and cable modem is horribly overpriced locally.

any advice or tips greatly appreciated.

aem sends...
aemeijers@att.net



Re: maximum number of devices on POTS line? (a tale of dialup woe)


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None of the remedies you tried will correct that problem!

Rewire the house.  Run CAT5 cable everywhere.  Pull enough to
run not just your telephone lines, but at least a couple of
10baseT Ethernet links to each room.  Or do it right and pull
enough cable for two phones and two Ethernet links in each
*corner* of every room!

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And it won't work.

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Everything you described fits the wiring you've indicated.  With
untwisted pairs you will have crosstalk to anything and
everything (power wiring, between telephone wires, to Ethernet
cabling, etc).  E.g., it will pick up noise every time any
electrical switch is turned on or off anywhere in the house.

My bet is that you don't get the same sustained data transfer
rates in the house with everything hooked up that you do with
the laptop connected right at the demarc.  Note that the initial
connect speed merely shows that it *can* be good, not that it
stays that good for hours on end.

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How can it be fine if some phones won't break dial tone????  You
*should* be able to connect several extentions.  The only limit
should be when there are too many ringers and some of them won't
*ring*...  but all of them should be able to break dialtone.
That doesn't mean they should all work well if more than one is
offhook at a time though.  They might, or might not.  But each
one, when onhook, does *nothing* to change the line for any
purpose other than ringing.

Who ever did the "diagnostics" didn't do much... ;-)

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You are better off spending a couple hundred online.  You'll get
a better price anyway.  And both a punchdown tool plus a
crimping tool for RJ-45 connectors are good things to have when
you want to add or change something.  Put a piece of 1/2" or
5/8" plywood on the wall where you want all this to be centered,
and have a hook there for the tools too.  Mount the 110 blocks
and make it look like a pro did it!

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Part of the reason for running CAT5 (rather than CAT2) is because
some day that will change, and you will want to use the house wiring
for Ethernet.

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--
Floyd L. Davidson            <http://www.apaflo.com/floyd_davidson
Ukpeagvik (Barrow, Alaska)                         floyd@apaflo.com


Re: maximum number of devices on POTS line? (a tale of dialup woe)



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REN is ringers, period. Nothing should alter pulling dial tone.

The modem speed with your laptop is irrelevent; when connected at the
demark it refects the condition of the outside loop plant and loop card;
be it in a SLC or the CO.

Either your IW is farkeled [engineering term] or one or more of your
devices is. I bet the wiring.

Connect all your gadgets up right at the demark. What happens?

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You might look for jacks that got wet and corroded.

Unplug everything and measure the resistance tip to ring from the
demark looking INTO the house. It should be 100Kohms or better. If
that's good, short tip to ring there, and go jack-to-jack and measure
the resistance of the loop. {Make up a modular cord for the ohmmeter}
It should be only a few ohms.

--
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: maximum number of devices on POTS line? (a tale of dialup woe)



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(snip)
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out,

Nothing obvious from visual inspection, but I realize that doesn't always
mean much. No painless way to plug anything other than laptop or a desk set
into the demarc- need to find my box of spare cables, and see if I still
have a 50-foot rj11.
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Thanks- I'll try that when I find the box with my VOM in it, and my box of
extra rj11 pigtails and such.... (unpacking is a LOT more tedious than I
remember. And the lawn keeps growing...)

aem sends....



Re: maximum number of devices on POTS line? (a tale of dialup woe)


On Sun, 28 Aug 2005 17:11:19 +0000, David Lesher wrote:
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If that doesn't do it, consider adding a battery in series with the line.
Telcos sometimes do that when they can't get enough loop current. I think
you need 17ma to trip off-hook, but it has been a few years. You might
have to bypass the battery with a couple capacitors.

Re: maximum number of devices on POTS line? (a tale of dialup woe)



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Come on.. No one has ever needed a ahem Ethnic Loop Extender since
Beetles were new. If his loop is THAT long; Ma will handle same.

But I did think up an easier test for the OP.

Use a DVM ma range. Go across T-R at the demark. Note the current.  Then
go to each jack and look for roughly the same short circuit current.

They all should be oh 15-60 ma, I think. What I suspect you'll find is some
jacks have VERY low loop current; indications of a bad splice somewhere.

--
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: maximum number of devices on POTS line? (a tale of dialup woe)


On Mon, 29 Aug 2005 03:49:16 +0000, David Lesher wrote:

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(Ethnic slur deleted....)
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Makes sense. If it is near 15, I would be suspicious of the loop. I still
think the spec is 17ma, although 15 might squeak by. The bad splice might
be on the other side of the demarc.

Re: maximum number of devices on POTS line? (a tale of dialup woe)



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Hey; it was a generic ethnic reference...not even a slur.

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The point is twofold; if the loop current is low at the demark; yell
at Ma. If it's OK there but low at one/some/all interior jacks, you
know where to start looking in the wiring mess.

--
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: maximum number of devices on POTS line? (a tale of dialup woe)


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However, the OP said he could not *break* dialtone.  He did not
indicate /any/ problems with on/offhook supervision.  Hence I
see *no point* at all in measuring loop current.

Regardless, the spec is 20 ma (for the North American system,
and varies on other locations).  It must release lower than 18
ma, and and must hold at greater than 23 ma.  Loop current is
allowed to be as high as 120ma, but should never intentionally
be allowed to be greater than 60 ma.  Typcial values range from
25ma to 45ma, and today is current limited on most systems.
That means measuring loop current won't really give much of an
indication of the loop resistance.

Regardless, he said some phones would not *break* dialtone.
That means pressing a key to dial doesn't work.  Typically that
is the result of a low level, an off frequency tone, too much
/difference/ between the level of the two tones, or... too much
noise on the line.  It is possible that he has a bad connection
in the wiring which is causing low levels.  However, given that
he stated the whole wiring set is 1) a *mess*, 2) uses crimp
splices, and 3) is non-twisted pair, it seems as likely that
noise from crosstalk or power line influence is the problem.

Given that it is non-twisted pair cabling, it simply is not
worth the effort to trouble shoot it.  The best that it will do
is not good enough, and with many phones (meaning many cable runs),
it is *never* going to work right until proper twisted pair cable
is installed.

He might as well just install CAT5 cable and do it right.

--
Floyd L. Davidson            <http://www.apaflo.com/floyd_davidson
Ukpeagvik (Barrow, Alaska)                         floyd@apaflo.com

Re: maximum number of devices on POTS line? (a tale of dialup woe)


floyd@apaflo.com (Floyd L. Davidson) writes:


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Actually... I have another possibility.

Floyd is correct; I was somehow thinking 'getting' not breaking
dial tone. But I can see low current as a reason the DTMF pad
would not work..or is off freq...

The obvious reason some things will not work as some jacks:

    Polarity

An original 2500 without an optional polarity guard will not create
DTMF.  I suppose there is some recent junque that may act that way
as well.

So for the OP:

    When you have a "can't break" combination; do you hear
    DTMF from the phone, or not?

    Can you break dialtone with hookswitch dialing?
--
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: maximum number of devices on POTS line? (a tale of dialup woe)



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(snip).
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Well, that one I can rule out, at least. Plugged in by itself, the main 2500
phone works fine. I didn't think to try hookswitch dialing last time the
line seemed to get 'tired'. (also didn't think to try any of the spares.)
The modem upstream on the same string tone-dialed with no problem, but would
either not connect, or connect ultra-slow.

That is the maddening part- the problem doesn't seem real consistent. It can
work fine when I plug stuff in, then not work an hour later. Some days it
works fine with 5-6 devices, at least for awhile. Today I had to go down to
3 to connect at 36,0. Doesn't seem to matter which computer, but the
answering machine seems to cause more 'load' than the phones. In short, I
know the  house wiring needs replacing, but I have to wonder about the telco
loop, too, in spite of what the site visit diagnostic said when I moved in.

Guess I need to start shopping for a long drill bit, and looking around
online for some place that will give me a good package price on a DIY
110/cable/keystone/tool kit. Any recommendations?

aem sends....


Re: maximum number of devices on POTS line? (a tale of dialup woe)



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Set aside the modem speed issue for now. Can you dial and talk and
get rung at all jacks?


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I'd first make some tests...

--
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: maximum number of devices on POTS line? (a tale of dialup woe)



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(snip)
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On at least 4 of the 9 jacks, yes. Haven't happened to have a phone plugged
in the others when the infrequent incoming calls occur. I can dial out on
all of them- tested that while I was rewiring the sockets to the R-G pair-
half of them were on the former second line the previous owner had on the
Y-B pair.

Maybe I should change the whole house over the the Y-B pair, from the demarc
in? At least that wouldn't cost anything but time.  :^\\

aem sends....


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