Hello all you good people:
I am looking for a schematic that will recognize when a computer connects to a phone line Weather I am on the Phone or when the line is open or not in use. I was wondering if there is a simple solution like detecting a fax ring or modem. When you have a fax machine it can distinguish between a voice and a fax. How do they do this? Maybe this is the approach that I must use. Any way any suggestions will be of great help. I already have an off hook led that lights every time a call is being received or the line is in use. And what I want to do is to have a blue led to light when a fax or a computer comes on line on the same phone line. I wonder if I could use a Dtmf detector to do this. If so where can I get a schematic for this detector? Thank You for any information. Have a Merry Christmas and a Happy New Year.
Want a Schematic or how to.
Re: Want a Schematic or how to.
Hi.
What you are asking may not be precisely put.
..."a schematic that will recognize when a computer connects to a phone line Weather I am on the Phone or when the line is open or not in use."...
--->I don't think a computer will seize an already in-use line; and if the line is not in use, you already have...
..."I already have an off hook led that lights every time a call is being received or the line is in use."...
About ..."I was wondering if there is a simple solution like detecting a fax ring or modem. "...
--->Maybe you mean the handshaking tones instead of the word 'ring'? There is some initial tones heard when a fax machine answers; they are meant to signal a human that a non-voice device is answering. Later in the communication, the modem puts out handshaking protocols that would need a microcontroller to interpret and to act as you wish.
..."When you have a fax machine it can distinguish between a voice and a fax. How do they do this? "...
--->Because there is a computer chip inside the machine, programmed to read and detect and act upon different 'noises' accordingly.
It will take an elaborate design to come up with what you MAY want; with a dosage of programming too.
About ..."what I want to do is to have a blue led to light when a fax or a computer comes on line on the same phone line."...
---> If your computer or fax 'comes on line' while the line is in use, there is something wrong with your systems.
About ..."I wonder if I could use a Dtmf detector to do this. If so where can I get a schematic for this detector?"
---> The DTMF detector schematics are abundant on the net and data books; but you are wondering wrong, as DTMF has nothing to do with telephone line seizing.
Sorry to dissapoint you.
Miguel
What you are asking may not be precisely put.
..."a schematic that will recognize when a computer connects to a phone line Weather I am on the Phone or when the line is open or not in use."...
--->I don't think a computer will seize an already in-use line; and if the line is not in use, you already have...
..."I already have an off hook led that lights every time a call is being received or the line is in use."...
About ..."I was wondering if there is a simple solution like detecting a fax ring or modem. "...
--->Maybe you mean the handshaking tones instead of the word 'ring'? There is some initial tones heard when a fax machine answers; they are meant to signal a human that a non-voice device is answering. Later in the communication, the modem puts out handshaking protocols that would need a microcontroller to interpret and to act as you wish.
..."When you have a fax machine it can distinguish between a voice and a fax. How do they do this? "...
--->Because there is a computer chip inside the machine, programmed to read and detect and act upon different 'noises' accordingly.
It will take an elaborate design to come up with what you MAY want; with a dosage of programming too.
About ..."what I want to do is to have a blue led to light when a fax or a computer comes on line on the same phone line."...
---> If your computer or fax 'comes on line' while the line is in use, there is something wrong with your systems.
About ..."I wonder if I could use a Dtmf detector to do this. If so where can I get a schematic for this detector?"
---> The DTMF detector schematics are abundant on the net and data books; but you are wondering wrong, as DTMF has nothing to do with telephone line seizing.
Sorry to dissapoint you.
Miguel
- Abolish the deciBel ! -
Re: Want a Schematic or how to.
I don't have a schematic but there is a DTMF chip. Also, Ramsey electronics has several kits that deal with DTMF and they are on the web. Sorry I can't be more help but I'm a newbie at this.
Who is online
Users browsing this forum: No registered users and 145 guests