Author Topic: Different type of dialing out Problem  (Read 176 times)

Offline tommycam

  • *
  • Posts: 55
Different type of dialing out Problem
« on: August 12, 2019, 02:07:42 PM »
Hello All,

I have been aided before with a dial tone that won't break when dialing. Now the problem is a little different.

I have two phones, a Deco Tel Candelstick rotary and a Push Button Bell Princess. When dialed, the dial tone goes silent as it is supposed too. The problem is after dialing a number, I get the phone company's "sorry the number you've dialed cannot be completed. . . " That's for both of them.

Just a FYI, I do have another rotary phone that dials out from the same wall jack. I believe that eliminates that as the problem.

Any advice or direction is appreciated.
Tom


Offline Key2871

  • **
  • Posts: 1538
Re: Different type of dialing out Problem
« Reply #1 on: August 12, 2019, 05:37:46 PM »
The system is getting incomplete information, from one of your phones. I would disconnect all but one, try that, if the problem goes way you know something from one of the other sets is causing a problem, go through all your phones, one by one keep track of what you find.
That's what I've done before and it's worked. I find the culprit quickly.
KEN

Offline tommycam

  • *
  • Posts: 55
Re: Different type of dialing out Problem
« Reply #2 on: August 12, 2019, 07:23:36 PM »
Ken,

Thank you for the suggestion.

I have only two phones on the same line. The other one is in the basement and it is wall phone that hasn't been moved in years. I'll take it down and try it.

Thank you again,
Tom

Offline Jack Ryan

  • **
  • Posts: 960
Re: Different type of dialing out Problem
« Reply #3 on: August 12, 2019, 09:33:04 PM »
I think I'd try with one phone connected at a time.

Unusual for both to go faulty at the same time but possible.

The rotary dial phone might have a slow dial, the princess DTMF frequencies might be out of adjustment.

Jack

Offline tommycam

  • *
  • Posts: 55
Re: Different type of dialing out Problem
« Reply #4 on: August 13, 2019, 12:04:51 AM »
Jack,

Thank you for your input - it is appreciated.

What's a DTMF?

Offline CanadianGuy

  • *
  • Posts: 146
Re: Different type of dialing out Problem
« Reply #5 on: August 13, 2019, 12:30:59 AM »
Dual tone multi frequency. Touch tones basically.

Offline Jack Ryan

  • **
  • Posts: 960
Re: Different type of dialing out Problem
« Reply #6 on: August 13, 2019, 12:55:03 AM »
What's a DTMF?

Sorry about that. As Canadianguy pointed out, it is the generic acronym for "touch tone" or "tone dialling". It stands for "Dual Tone Multi Frequency". There is a different combination of two tones generated for each button on the keypad.

On older DTMF dials, the tones are generated by oscillators made up of a coil, a capacitor and a transistor. This type of DTMF dial had a habit of getting "out of tune" so that one or both of the tones were not at quite the right frequency. When this happened, the exchange (CO) had trouble recognising the tones and sometimes the wrong digit was recognised and sometimes no digit was recognised.

Newer DTMF dials use a much more stable crystal or ceramic oscillator to generate the tones.

Regards
Jack

Offline tommycam

  • *
  • Posts: 55
Re: Different type of dialing out Problem
« Reply #7 on: August 13, 2019, 12:29:56 PM »
Thank you for the explanation on the DTMF.

Is it difficult to repair because I tried testing the phones one at a time and nothing changed. I was hoping this method would work.

I know WD40 for the slow dial, but is the DTMF difficult? If it is, I'll use it as display piece.

Thank you all again!
Tom

Offline Jim Stettler

  • Global Moderator
  • *****
  • Posts: 4170
Re: Different type of dialing out Problem
« Reply #8 on: August 14, 2019, 08:36:58 PM »
Sorry about that. As Canadianguy pointed out, it is the generic acronym for "touch tone" or "tone dialling". It stands for "Dual Tone Multi Frequency". There is a different combination of two tones generated for each button on the keypad.

On older DTMF dials, the tones are generated by oscillators made up of a coil, a capacitor and a transistor. This type of DTMF dial had a habit of getting "out of tune" so that one or both of the tones were not at quite the right frequency. When this happened, the exchange (CO) had trouble recognising the tones and sometimes the wrong digit was recognised and sometimes no digit was recognised.

Newer DTMF dials use a much more stable crystal or ceramic oscillator to generate the tones.

Regards
Jack

Early round button trimlines used oscillators , however as early as 1968-69 some  also used tone generating IC chips (10 and 12 button sets). By the mid 70's many of the rd button trimlines were getting converted to the IC's. I think all TT picture phones used IC's/
Jim
You live, You learn,
You die, you forget it all.