That can be as simple as a resistive voltage divider on the input.
Do you have any information regarding the amplitude of the
call-waiting tone relative to the data signal?
Telephony
Feb 06, 2007
32 Replies
The calling tone is 80 Vrms (more or less 10 Vrms). So 1,41*90 Vpeak =
127Vpeak. And there is the necessity of capacitors to filter the DC signal when the phone is not being used (about 48Vdc). About call-waiting tone signal, It is a acoustic signal. I measured 0,2-0,5Vrms but my multimeter isn't true rms.PH
VRMS
We call that the "ringing signal".
J F I followed you mesgs here a little bit. did a search on google and came up with this one:
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question: does this work? do you need a special modem to detect the tone? rw
I am and my multimeter are very fast. I am joking :-)
My thought: provided that it is a acoustic/audible signal, that has the same amplitude when I am talking to telephone :-) Or no? hahahaha, that is, maybe it isn't necessarily true!
Do you know any way to measure it?
PH
one:
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It works really. Read the past messages! You can get the same function adding the string +PCW=1 if your modem supports call waiting. But we want to learn to make that. Do you understand? We don't want only to use the modem :-)
PH
Yes, it works. Read some of the OP\'s posts to that effect.
You need a modem which supports call-waiting detection. The spec is
provided on the web page, I think.
Why is difficult to find those informations? Google for "+PCW=1 modem v 92" and you will find only few pages. Why?
Pedro Henrique
JF,
What do OP mean, please?
PH
if you're talking about the AT Hayse commands, I find them easy.
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ect..
"I\'m never wrong, once i thought i was, but was mistaken"
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5
easy.http://www.modem.com/general/extendat.htmlhttp://www.modemsite.com/56k/hcf9.asp
Only one of them refers to +PCW string. I want to mean that those informations aren't found easily from modem manufacturers.
PH
Original Poster. That is, the poster who started the thread.
Probably because its not really a "hot" topic.
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