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Phones ringing

  1. Feb 22, 2008 #1

    Danger

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    :grumpy:This has been bugging me for years, but I never thought to ask about it before.
    I always thought that the 'ring' trigger signal was just sent to the phone from outside and set it going. What I've noticed, though, is that two phones on the same line don't ring at the same time. It's very annoying. Even worse at home, since we have 2 cordless phones. The base unit on one of them rings first, then the base of the other, then the first handset, and finally the 2nd handset. That's a lot of ringing for someone who doesn't care for extraneous noises.
    I can understand that the base unit might have to redirect the signal to its own handset, and thus cause a delay between them (but this is about 2-3 full seconds), but why on Earth are the bases staggered? It happens at work, too, and at my old house with no cordless units at all--just regular extension phones.
     
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  3. Feb 22, 2008 #2

    Moonbear

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    I don't have an answer to your question, but I can "one up" you on weird phone behavior. I had a cordless phone COMPLETELY unplugged from the wall (base station unplugged from phone jack and power cord unplugged) and the dang thing would STILL ring whenever a call came in for months (it was dead if I tried to answer it...so I was sure the battery was running out). I finally had to yank out the battery to stop it. (If it rang after the battery was removed, I was going to post about it in S&D :biggrin:).

    Anyway, I think that means the ring is generated from within the phone, not from the phone line.

    Best way to fix it is to turn off the ringers on all but one phone. That's what I've done. My phone in the living room is still on, and if I'm awake, I can hear that from all the other rooms in the house, but all the other ringers are off, so if I'm asleep, they don't wake me up.
     
  4. Feb 22, 2008 #3

    Evo

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    The ringer is inside the phone and is set off by an electrical impulse sent from the phone company. We used to refer to it as the "ringer equivalent". Some old Western Electric phones had ringer equivalents of 5.0 (very strong), some of the free giveaway phones that came out had RE's of 0.0, meaning no audible ring.

    I'm not sure what it is causing your problem danger. Perhaps it is the ringer equivalents, probably exacerbated by the quality of the bases sending signals to the handsets.
     
  5. Feb 22, 2008 #4

    Danger

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    That must be it, then, since the other phones aren't cordless and the problem is less pronounced with them. Thanks.
    Good idea about muting the ringers, Moonbear. I'll give that a try (if W lets me; they're her phones).
     
  6. Feb 22, 2008 #5

    mgb_phys

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    Real phones with a dial and a bell were rung by the line (a 48V ac signal which is surprisingly painfull for such a low voltage) modern phones detect the signal and sound a peizo buzzer, the line still sends the same signal, phone people are obsessed with backwards compatibility.
     
  7. Feb 24, 2008 #6

    NoTime

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    A standard phone line has a 48v DC on hook voltage with about a 600 ohm impedance.
    The ring signal is around 90v AC, but it varies a bit.
    Yea! Its a bit painful :wink:
     
  8. Feb 25, 2008 #7
    I suspect that you, like I, had the experience of installing a phone line at the moment someone called. A SHOCKING sensation!
     
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