If it is a "newer" phone, the 6 ounce plastic pushbutton kind, I pick up the handset, dial 1 and listen there is LOUD crosstalk.
If I unplug that and go dig out my ancient old ITT bell rotary 3 pound desk phone from decades ago and try the same there is NO crosstalk.
(And I think this might be contributing to noise with the modem, loss of connections now and then, etc)
Any bright ideas about what I might to combat some of this? Use the cord to make a wrap or two around a ferrite torroid? Anything else? (cheap new phone is line powered, not wall powered)
The only thing I can think of, is that your phone is not wired correctly, or does not meet proper standards for your telephone company.
Is this a phone that is approved by your telephone company? Or, is this one of these cheap bargain phones?
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Jerry G. =====
If it is a "newer" phone, the 6 ounce plastic pushbutton kind, I pick up the handset, dial 1 and listen there is LOUD crosstalk.
If I unplug that and go dig out my ancient old ITT bell rotary 3 pound desk phone from decades ago and try the same there is NO crosstalk.
(And I think this might be contributing to noise with the modem, loss of connections now and then, etc)
Any bright ideas about what I might to combat some of this? Use the cord to make a wrap or two around a ferrite torroid? Anything else? (cheap new phone is line powered, not wall powered)
When you say 'cross-talk', is it other people's conversations or echoes? Does it happen with handset plugged straight into the wall jack? Are there any other extension sockets on your line in your house?
They can hear it too but not at a lower volume than here
And I loved the comment about whether this was a certified phone or not. When was the last time your phone company came out and did product certification?
Many countries have a certification scheme. In the UK telecoms products used to (still?) carry a green triangle or a red circle lable to indicate compliance with that scheme.
What is "it?" Static, echo, CB radio, AM broadcast radio, buzz, hum, etc. Until we know that, there is no realistic way to sort out what is the problem.
Whether or not it is Certified may give a clue to the problem. I'm sure the person who posted the question is glad you enjoyed the question. If you are so smugly smart why did you post your cross-talk problem?
"Don Taylor" schreef in bericht news: snipped-for-privacy@scnresearch.com...
Crosstalk is about unwanted signal transfer between two (telephone)lines, so two sets of wires. So what other line do you hear after dialing that 1? Can't imagine crosstalk in the last 4 foot cord where you are the only user. So what do you hear? Yourself? Then most likely the antilocalcircuit in your phone is broken. The old machines used transformers that are almost undestructable but the new electronic circuits are more sensitive. Other possibilties are wrong wiring and bad contacts.
Do you achieve the same result if you keep the modemcard out? Then the above stands. If not, you have to look for more precisely for bad contacts between phone and modem. That RJxx jackets sometimes get lame contacts. The plug also can be damaged. I met both cases several times.
If you really hear another line, it's almost sure the impedance matching between line and phone is very bad. Most likely some circuit in the phone became defective although wrong wiring and bad contacts are also a possible cause (as always).
I don't mean to be sarcastic about this but when AT&T sells itself and all the providers in the country seem to have realized that they can make LOTS more money trading cell phone contracts than they can making telephones... I suspect whoever might be left in the little office somewhere who's job it was to certify compliance just might have turned out the light and been outsourced without anybody noticing.
I was answering the question I was asked, "can the person on the other end of the phone hear this same conversation that I'm hearing or is it strictly limited to my end.
Well, I was thinking someone might have a list of moderately simple techniques that could kill the noise, I searched and didn't find any such list, before I even asked the question.
Having now checked ALL the phones I have here and there the ONLY certification I can see on any one of them is that a couple claim they comply with Part 68, which if I remember correctly is that they aren't supposed to radiate enough to interfere with anything else but unless I've forgotten Part 68 said nothing about a device not being interfered WITH. (And the old "real AT&T phone" has a ringer equivalency, but that seems like it went out of style about the time AT&T lost the ruling against Dataphone and connecting anything other than AT&T equipment to the line. I can remember getting a letter from the phone company 30 years ago when they did a ringer sweep of the town and sent warning letters to everyone who had a greater load than the number of phones they were paying for.)
So what's the certification ruling about phones not being subject to cross talk? I 'm curious. We've got a federal documents repository downtown and I'll go look it up.
Conversation from somewhere else, that was why I called it crosstalk rather than echo. And as I said, identical results if I take the pair of phones outside to the terminal block and repeat the experiment there with no inside wiring, no modem, no computer.
I've looked at jack and plug, both appear to be clean, not corroded, not badly bent, pretty good looking to me.
By eliminating all the inside wiring and the computer and everything to the outside jack, and the problem persists, it seems like we are getting closer to the problem. But I'm still not seeing any solution other than going back to the 1970's Bell rotary desk phone, yet.
If you get the same problem when you move the phone to another socket then it sounds like the phone is faulty. Unless it's some fancy telephone I would just trash it.
That third party conversation is picked up somewhere along the line. Most likely on a place the lines are running parallel over some distance. Your line looks like an antenna that picks up the radiation from the other line. Most likely the cause is lack of correct termination on the phones side if there is some termination at all. Maybe the internal state of the phone changes after pressing the 1, maybe the exchange makes some connection when you do. Nevertheless, your phone is either defective or suffers from a design flaw. You can open it and look for broken contacts or bad solder joints but with low chance for succes. You could try to put a resistor in the phone to correct termination but I can't be sure to tell where and how even if I have the phone in my own hands. (If you knew you should not have to put the question in the first place.) You can buy or borrow another phone just to check your findings. Think you have to buy another one anyway if you want to get rid of that crosstalk. They are not that expensive after all.
How do you know it is cross talk and not some other signal, such as a radio station's talk show?
A few years ago, I had a phone which seemed also to pick up a radio station. It was so bad that when I tried to use it to dial up my ISP, the computer said it couldn't find the dial tone. The problem was solved by using a filter from Radio Shack. I only used the filter with the computer, so I don't know whether it would have improved the sound quality if I had used it with the phone.
Usually I consider it an act of desperation to buy anything from Radio Shack, and it was certainly one in this case, but they actually had a solution when no one else did.
--
Ignorantly,
Allan Adler
* Disclaimer: I am a guest and *not* a member of the MIT CSAIL. My actions and
* comments do not reflect in any way on MIT. Also, I am nowhere near Boston.
From the conversation going on it is going to be one personal talk show!
The elderly friend of mine who kept telling me he had this problem, and I kept dismissing it as just one more example of elderly crankiness.. until I happened to drive the 40 miles to go see him, tried to make a call and the conversation on the phone line was louder than usual phone conversations! And that was after dialing a single digit to just silence the dial tone. And his hearing/ tinnitus is worse than mine. No wonder he had complained.
Now a filter sounds like a possibility. Have you got more details about what I'm supposed to look for? The last time I went in looking for parts at Radio Shack the minute they realized I wasn't going to make them a cell phone contract commission they went back to talking among themselves.
And, I have an honest suggestion, for the folks who discussed "certified" phones. Choose a phone supplier, you get to pick the one that you think has the best chance. The next time you might be there, ask the salesman if the phone is really "certified" and see if they can tell you something to make you believe they actually know what they are talking about. To be honest I would be REALLY surprised if they know what you are talking about and even more surprised if they can actually show anything that confirms this. Please report back, I would love to hear what the outcome was.
Someone suggested the phone company would sell "certified" phones and I should buy one of those. I honestly wouldn't think that Qwest or Verizon even sells non-cell phones any more, I'll call them up and tell them I want to buy one of the certified ones and see what happens. But before I started this I did call and they offered to come check the inside wiring ($50 plus hourly I think)
I worked for Tek decades ago and we had our own EMI cert lab, but I never did any cert work. I wonder if they dumped that long ago, along with the 80% of the workforce.
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