Hum from phone wires running next to mains?

Ivor Jones wrote:


cut
Trolling and obnoxious behavior is something only yo can stop. Meanwhile others are free to call you a social crossposting misfit.
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in message
[snip]
: Trolling and obnoxious behavior is something only yo can : stop. Meanwhile others are free to call you a social : crossposting misfit.
Yes mother.
Ivor
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On Fri, 14 Mar 2008 08:53:29 -0000, "Ivor Jones"

Convention and standard, it's a fine line you're trying to draw mainly for an argumentative state to support a position that is obviously not agreeable to others and obviously not what was intended for usenet by your own observations.
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[snip]
: Convention and standard, it's a fine line you're trying to : draw mainly for an argumentative state to support a : position that is obviously not agreeable to others and : obviously not what was intended for usenet by your own : observations.
So explain to me just why, in 10+ years, this is the first time a "complaint" has arisen. It's been "agreeable to others" until now, what has suddenly happened..?
Ivor
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On Sat, 15 Mar 2008 12:36:48 -0000, "Ivor Jones"

Incorrect. Someone not saying it's disagreeable is no more evidence that it's agreeable to them than that it wasn't.
When someone didn't say anything they were being patient, courteous, thinking you must just be ignorant and a bit slow in the mind but will figure it out eventually. When you start acknowledging you do it and trying to defend it, NOW you actually see what people think. It can't just be coincidence that more than one person has something to say about it when you've never had anyone say it was acceptible or a good idea.
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wrote:
[snip]
: >So explain to me just why, in 10+ years, this is the : >first time a "complaint" has arisen. It's been : >"agreeable to others" until now, what has suddenly : >happened..? : > : >Ivor : : Incorrect. Someone not saying it's disagreeable is no : more evidence that it's agreeable to them than that it : wasn't.
Incorrect. No evidence is precisely that. If there is no evidence against someone then a conviction is not possible.
: When someone didn't say anything they were being patient, : courteous, thinking you must just be ignorant and a bit : slow in the mind but will figure it out eventually.
Or they didn't have a problem with it.
I'm getting bored now, please go away.
Ivor
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On Sun, 16 Mar 2008 05:32:48 -0000, "Ivor Jones"

If there were no evidence, but THERE IS, WE'RE TELLING YOU!

Wouldn't that be even more boring?
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| |
| | : >> | : >> [snip] | : >> | : >>: > Can't say as it caused me any issues here except the | : >>: > fact of ": :" putting it down to the second level of | : >>: > quoting as if you had used "> >" | : >> | : >> Fixed. That *was* a misconfiguration ;-) | : > | : > Not quite. You're now quoting with ": >" compared to | : > ": :" previously. | | So what's the problem with that..?
The problem is it looks like the text you are quoting was quoted by someone else before you.
| No, don't bother answering, I've had enough of this pointless argument.
Why are you trying to say you not doing that which you are doing?
| You don't like my quote style, tough. Don't read my posts. Simple, problem | solved.
That would be a simple solution. I bet some already have.
What I am trying to do is get you to realize what it is you are doing. So far, your explanations DO NOT MATCH UP WITH what you actually ARE DOING. Maybe it is because you just don't see it for some reason. I don't know what the reason is. But I'm to keep on you until you at least understand that you are putting on TWO layers of indenting (first "> " and then after that ": " to the left of it).
--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
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On Sun, 9 Mar 2008 21:07:16 -0000, "Ivor Jones"

Thank you.
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(As you suggest, I will not get the flat ready made extension cable which I guess is made from flexible multi-stranded wires.)
Is the sort of cable sold in the UK specifically for domestic telephone wall sockets (wuth single stranded wires) usually made up as "twisted pair" in the way you are recommending?
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Foxtrot wrote:

No I don't know why it is still used as most people in the UK seem to have adsl connections nowadays (not just phones)
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Foxtrot wrote:

Much will depend on the power and light wiring method used and the quality of the cable used to carry your telephone circuits. What do you mean when you say "flex". I suspect you'll be amused to learn that in the USA that word is electricians short hand for flexible metallic conduit. I doubt that United Kingdom "flex" is anything like Flexible Metallic Conduit a photograph of which can be found at <http://www.tradexpro.com/product_catalogs/machinery_electronics/cable_wire/in-commerce/product/picture_fullsize/flexible_metallic_conduit.html?env=img-106372-- .
The best way to reduce the amount of noise in telephone lines is to use station cable that has the wire pairs continuously twisted around each other. In this way any electro magnetic fields that might otherwise induce an unwanted noise into the circuit is self canceling in the twisted pair of wires. Even with good quality station cable best practice is to maintain at least several inches of separation between the telephone cables and the electrical power and light wiring.
--
Tom Horne

"This alternating current stuff is just a fad. It is much too dangerous
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<http://www.tradexpro.com/product_catalogs/machinery_electronics/cable_wire/in-commerce/product/picture_fullsize/flexible_metallic_conduit.html?env=img-106372-- .
I believe I can help here. Rightpondian "flex" <> Leftpondian "cord"
--
Graham

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Correct.
The usual meaning is a flexible, rubber or PVC covered, two or three core cable, used to connect an appliance to its electrical source. This may be via a plug and socket in the case of something like a vacuum cleaner, or fixed as in the cable suspending a light fitting from the ceiling fixture.
--
Stuart Winsor

From is valid but subject to change without notice if it gets spammed.
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Can't comment on the hum ... but it looks like others have.
One contribution I would make is that you are aware that your phone service will support 4 REN and that each phone is normally 1 REN, meaning that you can have a maximum of 4 phones. My parents had more of this and whilst from their perspective it seemed to work (they could call out), it stopped people from calling in because their phones stopped ringing.
So be aware that if you are adding four or five additional phone sockets that you won't be able to use all of them (at the same time).
--
Brian Cryer
www.cryer.co.uk/brian
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wrote:
| |>I am in the UK and want to make several phone extensions. |> |> QUESTION: I would like to know I this will increase the level of hum. |> |> ISTR UK phones have a transformer and some other components to |> neutralise hum but would that be good enough to prevent hum from a messy |> setup like mine? Some details are below. |> |> ------------------------- |> |> In my situation the phone extension wires and the mains wires will run |> close to one other. |> |> There will be about four or five additional extension phone sockets. | | Can't comment on the hum ... but it looks like others have. | | One contribution I would make is that you are aware that your phone service | will support 4 REN and that each phone is normally 1 REN, meaning that you | can have a maximum of 4 phones. My parents had more of this and whilst from | their perspective it seemed to work (they could call out), it stopped people | from calling in because their phones stopped ringing.
I used to see phones rated in terms of their "ringer equivalence" here in the USA. These numbers were, for some phones, as low as 0.2. I do not recall ever seeing one about 0.9. That would suggest to me that you could readily have more than 4 phones on such a phone circuit. I never had any reason to actually do a scientific test of this.
| So be aware that if you are adding four or five additional phone sockets | that you won't be able to use all of them (at the same time).
Or check your phone specs for an REN or ringer equivalence number.
If you want to put DSL on your phone line, I also suggest a splitter at the entrance of the phone line and a separate NON-branching higher grade (e.g. twisted pair) wire for the run from the DSL side of the splitter to the intended connection.
--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
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There is obviously a significant difference in the phone systems in the two countries. Our phones have the bells in parallel and if thee are too many the wrong impedance is presented to the exchange, and no ringing voltage will get sent. I have never seen a UK approved phone with a REN less than 1, but there were plenty of 2s & 3s about at one time.
You can buy a REN booster ( a mains powered device) which allows many more phones.
--
From KT24 - in "Leafy Surrey"

Using a RISC OS computer running v5.11
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To me, Phil's post illustrates how *similar* the our systems are, and I strongly suspect that the reason why we don't see REN <1 is that the approval rules specify the figure quoted should be an integer between 1 and 4. Powered devices like DECT base-stations and FAX machines don't need to supply any significant ringing current from the line, they just need to sense the AC waveform to trigger the ringing.
REN is a bit of an anathema these days IMHO. A good get-out for the support drones. ( For the North Americans) What is unusual with the UK system apart from our "special" plug and receptacle instead of an RJ11, is the fact that we use a third wire which couples all the ringers in parallel to a capacitor in the master socket to which the incommer is connected. Many modern phones do not even use this "bell wire" and just use the A and B wires (tip & ring).
--
Graham

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"Graham." wrote:

... snip about ringer specs on phones and lines ...

In North America again (I don't know about elsewhere) the normal phone uses 3 wires to connect to the two wires of the phone circuit. The yellow wire carries the ring signal. Just disconnect that and the phone won't ring, and the load is zero.
--
[mail]: Chuck F (cbfalconer at maineline dot net)
[page]: <http://cbfalconer.home.att.net
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I don't recall any system in North America that put ring voltage on a separate wire. The yellow wire is generally not connected unless one 4-wire cable is used for two separate telephone lines.
In North America the "normal" line uses only 2 wires. The audio signal is applied between the "tip" and the "ring" of a single pair. "Ring Current" and "Loop Current" are also applied between the Tip and the Ring of the same pair.
Commonly used drop cable has four wires: Green is the Tip and Red is the Ring (positive and negative, repectively for the DC loop current), while the Yellow and the Black wires are not used. (Note that the DC voltages used by telephone companies are negative with respect to ground, hence for DC the Tip wire is at ground potential, and the Ring wire has a negative potential. But the Tip is not at ground potential for Ring Current or for the audio signal.)
One configuration often seen includes a second line on the same cable, using Yellow and Black as Tip and Ring.
Historically the Yellow wire was, for a few years, used for a small AC voltage (nominally 6.8 volts) to power a lamp circuit on some telephone set models.
Another historical use had the Yellow wire as a ground for party line service from the old style mechanical switching systems (such as the Step or Stroeger switching systems once used by the Bell System and by Automatic Electric). On those systems the ring current was applied between either Tip or Ring and ground, which was supplied to the telephone set on the Yellow wire.
--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson
Ukpeagvik (Barrow, Alaska) snipped-for-privacy@apaflo.com
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