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

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... snipped-for-privacy@att.net

Reply to
ameijers
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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!

And it won't work.

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.

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... ;-)

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!

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.

Reply to
Floyd L. Davidson

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?

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.

Reply to
David Lesher

(snip)

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.

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....

Reply to
ameijers

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.

Reply to
John McHarry

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.

Reply to
David Lesher

(Ethnic slur deleted....)

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.

Reply to
John McHarry

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

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.

Reply to
David Lesher

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.

Reply to
Floyd L. Davidson

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 {Doh!} 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?

Reply to
David Lesher

(snip).

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....

Reply to
ameijers

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

I'd first make some tests...

Reply to
David Lesher

(snip)

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....

Reply to
ameijers

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